PLANING BOAT WITH TWO VORTEX GENERATORS

Abstract

Method and apparatus of various embodiments of a planing boat or vehicle supported by a system of three cambered planing surfaces, comprising two transversely set apart forward surfaces generating on their inner edges two counter-rotating tip vortices resulting in an ascending flow further aft downstream of the gap between these two forward surfaces, and one center aft surface, which sections are displaced higher vertically and inclined nose-dive relatively sections of the forward surfaces by the height and slope angle of the ascending flow at their location, so that the angles of deadrise and moduli of negative angles of inclination of the aft surface gradually increase along the span from the center plane outwards, embodying in special angular and spatial relative arrangement of said three planing surfaces and configuration of the aft surface with its half-planes curved upwards and twisted downwards in a substantially hyperbolic manner.

Claims

1. A planing boat or a vehicle with its center plane, which boat or vehicle is moving at a speed corresponding to a Froude numbers of about or greater than 3 and employing to support at least a part of its weight at least one hydrodynamic system of three cambered planing surfaces with its center plane coinciding or being parallel to the center plane of the boat or vehicle, while said cambered planing surfaces skim along the surface of water and supposed to generate dynamic lift by means of only positive hydrodynamic pressure on their facing downward profiled wetted surfaces, and vertical longitudinal sections of said cambered planing surfaces feature base lines coinciding with the hydrodynamic base lines of their cambered profiles, which system of three cambered planing surfaces comprises: two forward planing surfaces transversely set apart both sides of the center plane of this hydrodynamic system, which two forward planing surfaces generate at their inner facing each other edges two counter-rotating tip vortices, so that the direction of rotation of the right-hand vortex is clockwise and the left one is counterclockwise in projection onto the transverse plane when viewed from the front, resulting in an ascending flow further aft downstream of the gap between these two forward planing surfaces, which ascending flow is characterized by negative angles of the slope relatively the level of the undisturbed water surface, and one aft planing surface located further aft of said two forward planing surfaces along the length of the boat or vehicle, at the center plane of said hydrodynamic system, at least partially within the limits of and affected by said ascending flow, and extending with its half-planes symmetrically both sides of said center plane of said hydrodynamic system, wherein in vertical longitudinal planes within the gap between said two forward planing surfaces sections of the aft planing surface are displaced higher than the base lines of the two forward planing surfaces by the heights determined by the ordinates of the rise of the surface of the ascending flow at the locations of said sections of the aft planing surface above the base lines of the forward planing surfaces, which positions of sections of the aft planing surface are defined by the leading edge points of said cambered profiles of said sections of the aft planing surface, and the base line of each of said sections of the aft planing surface is inclined relatively the base lines of the forward planing surfaces by the angle being equal to the sum of the negative angle of the slope of the surface of the ascending flow relatively the level of the undisturbed water surface at the location of said section of the aft planing surface and the difference between the positive angle of incidence of the base line of said section the aft planing surface relatively the local surface of water corresponding to the surface the ascending flow at the location of said section of the aft planing surface and the positive angle of incidence of the base lines of the forward planing surfaces relatively the level of the undisturbed water surface, so that, at least in some part within the width corresponding the width of the gap between the forward planing surfaces in projection onto the transverse plane, angles of deadrise of said aft planing surface and moduli of negative (nose-dive) angles of inclination of base lines of sections of the aft planing surface relatively the base lines of the forward planing surfaces gradually increase along the span of the aft planing surface from the center plane of the hydrodynamic system outwards resulting in half-planes of said aft planing surface curved upwards and twisted downwards in a substantially hyperbolic manner.

2. A planing boat or a vehicle according to claim 1, wherein the outer ends of at least some of said cambered planing surfaces are provided with end plates or deflectors.

3. A planing boat or a vehicle according to claim 1, wherein said two forward cambered planing surfaces made with variable angles of deadrise along their spans.

4. A planing boat or a vehicle according to claim 1, wherein at least some of said cambered planing surfaces made swept.

5. A planing boat or a vehicle according to claim 1, wherein said two forward planing surfaces represent bottom surfaces of two sponsons protruding downwards from the forward part of bottom of said boat or vehicle and transversely set apart both sides of the center plane of said boat or vehicle.

6. A planing boat or a vehicle according to claim 1, wherein the camber of at least some of said planing surfaces is the Virgil Johnson three-term camber.

7. A planing boat or a vehicle according to claim 1, wherein at least some of said cambered planing surfaces are made in the form of panels or planes that are separated from the bottom of the boat or vehicle and connected to the bottom by means of structural members.

8. A planing boat or a vehicle according to claim 7, wherein said structural members comprise struts and/or flanges.

9. A planing boat or a vehicle according to claim 7, wherein said separated from the bottom panels or planes are made with streamlined convex upper surfaces similar to the upper surfaces of hydrofoils.

10. A planing boat or a vehicle according to claim 7, wherein said separated panels or planes are provided at their bottom part with flat portions connecting the leading edges of said panels or planes and the leading edges of the cambered profiled portions of said bottom part of said separated panels or planes.

11. A planing boat or a vehicle according to claim 10, wherein in sections by vertical longitudinal planes said flat portions are aligned with hydrodynamic base lines of said cambered profiles.

12. A planing boat or a vehicle according to claim 7, wherein at least some of said separated from the bottom of the boat or vehicle cambered planing surfaces are made foldable or retractable.

13. A planing boat or a vehicle according to claim 7, wherein said two forward cambered planing surfaces are made separated from the bottom of the boat or vehicle and the aft cambered planing surface is made integrated into the aft part of bottom of said boat or vehicle.

14. Said planing boat or vehicle is a pontoon boat provided with at least one hydrodynamic system according to claim 7.

15. A planing boat or a vehicle according to claim 7, wherein at least some of said separated panels or planes are mounted on bottoms of streamlined floats located under the hull of the boat or vehicle.

16. A planing boat or a vehicle according to claim 15, wherein at least some of said streamlined floats are separated from the hull of the boat or vehicle, located at a certain distance vertically from the hull of the boat or vehicle and structurally connected to said hull of the boat or vehicle by means of struts.

17. A planing boat or a vehicle according to claim 16, wherein said streamlined floats are connected to the hull of the boat or vehicle by means of struts of elongated streamlined cross-sections, inclined relative to the center plane of the boat or vehicle so that the leading edges of said sections are located closer to said center plane of the boat or vehicle than the trailing edges of said sections.

18. A catamaran according to claim 7, wherein each of two forward separated panels or planes representing forward planing surfaces is mounted on the bottom of forward part of corresponding catamaran hull and one aft separated panel or plane representing said aft planing surface is located between catamaran hulls.

19. A boat according to claim 1, wherein two propulsion propellers are located upstream of the aft planing surface and downstream of the forward planing surfaces, each on one side of the gap between the two forward planing surfaces in projection onto the transverse plane, providing that the direction of rotation of the right-hand propeller is clockwise and the left one is counterclockwise when viewed from the front.

20. A seaplane or a wing-in-ground effect marine vehicle with take-off and landing gear employing the system of cambered planing surfaces according to claim 1.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0204] The accompanying drawings, which are incorporated herein and constitute part of this specification, illustrate exemplary embodiments, and together with the general description given above and the detailed description given below, serve to explain the features of the various embodiments.

[0205] FIG. 1 is a schematic diagram illustrating formation and utilization of ascending flow by the system of three dynamic lift surfaces.

[0206] FIG. 2 is a schematic diagram illustrating the side elevation view of a boat provided with the hydrodynamic system of three cambered planing surfaces comprising two forward vortex-generating planing surfaces separated from the bottom (left forward vortex-generating planing surface and its strut are conditionally removed) and one aft planing surface being integrated into the aft part of boat's bottom according to some embodiments, which diagram clarifies the spatial and angular arrangement of the three cambered planing surfaces following this invention.

[0207] FIG. 3 is a schematic diagram illustrating the plan bottom view of a boat provided with the hydrodynamic system of cambered planing surfaces according to some embodiments.

[0208] FIG. 4 is a schematic diagram illustrating the front elevation view of a boat provided with the hydrodynamic system of cambered planing surfaces comprising two forward vortex-generating planing surfaces separated from the bottom and one aft planing surface being integrated into the aft part of boat's bottom according to some embodiments.

[0209] FIG. 5 is a schematic diagram that illustrates the perspective forward bottom view of a boat provided with the hydrodynamic system of three cambered planing surfaces, wherein two forward vortex-generating planing surfaces made separated from the bottom and one aft planing surface is integrated into the aft part of boat's bottom according to some embodiments.

[0210] FIG. 6 is a schematic diagram illustrating the front elevation view of a boat provided with the hydrodynamic system of three cambered planing surfaces being separated from the bottom of the boat according to some embodiments.

[0211] FIG. 7 is a schematic diagram that illustrates the perspective forward bottom view of a boat provided with the hydrodynamic system of three cambered planing surfaces, wherein all three planing surfaces made separated from the bottom of the boat according to some embodiments.

[0212] FIG. 8 is a schematic diagram that illustrates an along the flow sectional view of a separated planing surface provided with hydrofoil-like concave upper surface according to some embodiments.

[0213] FIG. 9 is a schematic diagram that illustrates the perspective aft bottom view of a boat provided with the hydrodynamic system of three cambered planing surfaces, wherein two forward vortex-generating planing surfaces made integrated into bottom surfaces of sponsons and the aft planing surface is integrated into the aft part of boat's bottom according to some embodiments.

[0214] FIG. 10 is a schematic diagram illustrating the front elevation view of a boat provided with the hydrodynamic system of separated cambered planing surfaces being mounted on bottoms of three streamlined floats according to some embodiments.

[0215] FIG. 11 is a schematic diagram that illustrates the rear perspective view of a bottom of boat provided with the hydrodynamic system of separated cambered planing surfaces being mounted on bottoms of three streamlined floats comprising two forward floats separated from the hull of the boat and connected to the hull by means of streamlined profile struts installed obliquely relative to the central plane according to some embodiments.

[0216] FIG. 12 is a schematic diagram illustrating the front elevation view of a boat of catamaran configuration provided with the hydrodynamic system of separated cambered planing surfaces according to some embodiments.

[0217] FIG. 13 is a schematic diagram illustrating the front elevation view of a boat of catamaran configuration provided with the hydrodynamic system of separated cambered planing surfaces and featuring semi-submerged counter-rotating propellers arranged on the inner tips of forward vortex-generating planing surfaces according to some embodiments.

[0218] FIG. 14 is a schematic diagram illustrating the bottom plan view of a boat of catamaran configuration provided with the hydrodynamic system of separated cambered planing surfaces and featuring semi-submerged counter-rotating propellers mounted on the inner tips of forward vortex-generating planing surfaces according to some embodiments.

[0219] FIG. 15 is a schematic diagram illustrating the bottom plan view of a boat of catamaran configuration provided with the hydrodynamic system of cambered planing surfaces and featuring counter-rotating propulsion propellers arranged as separate units and positioned between the forward and aft lifting surfaces along the length of the boat in the wakes of inner tip vortices of forward vortex-generating planes, and supported by struts, brackets or propulsion drives according to some embodiments.

[0220] FIG. 16 is a schematic diagram illustrating the front elevation view of a single-keel boat provided with the hydrodynamic system of cambered planing surfaces with separated from the bottom foldable forward vortex-generating planing surfaces and the aft planing surface integrated into the aft part of the bottom of the boat according to some embodiments, wherein semi-submerged counter-rotating propulsion propellers arranged along the length of the boat downstream the forward planing surfaces and upstream the aft planing surface in the wakes of tip vortices of forward vortex-generating planing surfaces, and supported by foldable propulsion drives mounted on the bottom of the boat, while both the forward planing surfaces and the propulsion drives are shown in the operational unfolded position.

[0221] FIG. 17 is a schematic diagram illustrating the front elevation view of a single-keel boat basically corresponding to the embodiment of the FIG. 16, wherein both separated from the bottom forward planing surfaces and propulsion drives with propellers are shown in the retracted position.

DETAILED DESCRIPTION OF THE INVENTION

[0222] Various embodiments will be described in detail with reference to the accompanying drawings. Wherever possible, the same reference will be used throughout the drawings to refer to the same or like parts. References made to particular examples and implementations are for illustrative purposes, and are not intended to limit the scope of the claims.

[0223] FIG. 1 depicts a schematic diagram illustrating formation and use of ascending flow by the system of three planing surfaces. The diagram shows the perspective view of the system of planing surfaces comprising two forward planing surfaces FPS set apart transversely to the direction of flow FL and forming a gap between their inner facing each other edges IE, and the aft planing surface APS with its center plane section CPS arranged downstream of said gap.

[0224] The forward planing surfaces FPS being positioned in the flow FL generate dynamic lift by means of a positive pressure on their bottom surfaces. That coerces the ambient water to flow from the high pressure zones on bottoms of the forward planing surfaces FPS to the lower pressure zones over said inner edges IE up that results in rotational movement of masses of water around longitudinal axis and formation of a cord of tip vortices VX shedding from the inner edges IE and carried away by the flow downstream.

[0225] Correspondingly, for the above configuration of two transversely spaced forward planing surfaces FPS, the direction of rotation of the tip vortices VX generated by the inner edge IE of the right-hand forward dynamic lift surface is clockwise, and the left one is counterclockwise, when viewed from the front.

[0226] This counter-rotational pattern of motion of the water masses, initiated by vortices VX at opposite ends of the gap between the two forward planing surfaces FPS, causes the masses of water in the gap to move upward, while this disturbance of motion of water propagates downstream the flow.

[0227] Thus, these counter-rotating vortices generate a velocity field in the gap between said forward planing surfaces with a velocity component V.sub.VA directed upwards, which in combination with the velocity of ambient flow V.sub.0 results in an ascending flow with cumulative velocity V.sub.A downstream the forward planing surfaces FPS, while the vector V.sub.A is inclined at some negative angle to the to the direction of flow FL (i.e., turned counterclockwise if viewed from the right side of the picture and the port side of this hydrodynamic system).

[0228] So, the aft planing surface APS arranged amid this gap in the projection to the transverse to the flow plane and somewhat aft of the mentioned parallel-moving forward planing surfaces FPS could be inclined nose-dive and this way positioned more favorably in terms of reduction of the resistance of form, keeping at the same time some proper angle of incidence relatively the local oncoming ascending flow in order to generate required lift. That ultimately leads to a decrease in resistance and improvement in efficiency (lift to drag ratio) of such three-surface dynamic lift system.

[0229] The essence of this process is as follows:

[0230] In the case of placement of the aft dynamic lift surface APS within the range of ascending flow inclined at some negative angle to the to the direction of flow FL and corresponding nose-dive inclination of the surface APS by the angle (keeping at the same time the required angle of incidence relatively the local flow corresponding to the ascending flow), the directed upwards vector of the dynamic lift force L of the aft surface will be tilted forward in the direction of movement of the system (i.e., turned counterclockwise if viewed from the port side of this hydrodynamic system) by the angle corresponding to the angle of slope of the ascending flow , and the projection of said tilted upward lift vector L onto the horizontal plane will produce an additional forward-looking component T (being similar to some additional thrust) that reduces fluid drag and increases the fluid dynamic efficiency of the system.

[0231] To illustrate formation of the forward-looking horizontal component, the vector L in FIG. 1 conditionally shown inclined forward, while for real practical designs vector L can be tilted back creating a rearward projection onto the horizontal plane, which determines the resistance of this aft planing surface.

[0232] In this case, turning the aft surface APS to the nose-dive position corresponding the ascending flow will result in turning the tilted back vector L counterclockwise forward and its arrangement closer to the vertical with resulting reduction of the horizontal projection and, correspondingly, reduction of the resistance. Consequently, the difference in horizontal projections for inclined and non-inclined positions will determine the vector T.

[0233] This way the aft planing surface APS actually recovers some part of the energy spent by the forward planing surfaces FPS to disturb the incoming ambient flow and to deviate the masses of ambient water upwards relatively the undisturbed water surface in the form of generation of the ascending flow.

[0234] At the same time, under certain conditions corresponding, for example, to large angles of inclination of the ascending flow B and high hydrodynamic efficiency of the aft surface APS (determining low resistance stipulated by slightly tilted back close to vertical vector L with a small rearward horizontal projection in the non-inclined position), the vector L for the inclined position can indeed be tilted forward from the vertical and create only the pulling force T, as shown in FIG. 1.

[0235] This entire effect can be realized only if the configuration of the aft planing surface APS matches the shape of surface of the ascending flow, so that in each vertical longitudinal plane within the range of interaction, sections of the aft planing surface APS would be located in height in accordance with the height of the rise of the ascending flow above the undisturbed level of the water surface and, accordingly, above the forward planing surfaces FPS, and would be rotated an additional nose-dive angle, while providing the angle of incidence relative to the ascending flow required to generate the necessary lift L, which should determine the optimal relative arrangement of the forward FPS and aft APS planing surfaces in this hydrodynamic system.

[0236] Taking into account the shape of the cross sections and the spanwise distribution of the angles of inclination B of the surface of the ascending flow generated by two parallel counter-rotating vortex cords VX (created by the two forward planing surfaces FPS), the above requirements dictate the configuration of the aft planing surface APS (being necessary for the implementation of the positive effect of the ascending flow) with gradually increasing along the span angles of deadrise and modules of the additional negative angles of inclination of sections, which is embodied in the half-planes of the aft planing surface curved upward and twisted down in a substantially hyperbolic manner.

[0237] The indicated spatial and angular relative arrangement of the forward FPS and aft APS planing surfaces, as well as the configuration of the aft surface APS with its half-planes having substantially hyperbolic bending and twist, provide a significant reduction in drag and an increase in the hydrodynamic efficiency of both this hydrodynamic system and the boat or vehicle using such system in accordance with the provisions of this invention.

[0238] FIG. 2 depicts a schematic diagram illustrating the side elevation view of a boat according to some embodiments, wherein two separated forward vortex-generating planing surfaces arranged symmetrically on the left and right sides of boat's bottom and supported by struts, while the aft planing surface is integrated into the aft part of boat's bottom.

[0239] In this diagram the port-side forward vortex-generating planing surface with its strut is conditionally removed to clarify the positions of the forward and aft planing surfaces relatively each other, the undisturbed ambient water surface and the ascending flow generated by the forward vortex-generating surfaces.

[0240] In the diagram the boat 201 moves at operational speed corresponding Froude numbers of about or in excess of 3, along the undisturbed water surface W in the direction F. In this embodiment the boat 201 is provided in its forward part with two struts 202 supporting separated from the bottom of boat 201 forward cambered planing surfaces 203 (only starboard side surface and strut are visible in this elevation) represented by their profiled wetted areas (being hatched in this diagram) with their base planes 204 shown here coinciding with the hydrodynamic base planes of cambered profiles of their lowermost sections 205 and positive (i.e., measured clockwise in this diagram) angle of incidence 206 determined by the position of their base planes relatively the undisturbed water surface W, which forward cambered planing surfaces 203 generate dynamic lift and contribute the dynamic support of the boat 201 in motion.

[0241] The port and starboard cambered planing surfaces 203 set apart both sides of the boat's center plane and generate at their inner edges (facing each other and the center plane) two counter-rotating tip vortices, which create the ascending flow conditionally shown by the center plane surface line 207 in the gap between said inner edges and further aft downstream the flow.

[0242] The boat 201 is provided also with the third aft cambered planing surface 208 located in the center plane of the boat 201 at some distance aft from the forward planing surfaces 203, supposed to be integrated into the aft part of bottom and represented by its profiled wetted area being hatched in this diagram. This aft planing surface 208 features its leading edge 209, the exemplified base plane 210 shown here coinciding with the hydrodynamic base plane of cambered profile of its center plane keel section 211 and the positive angle of incidence 212 of this section 211 relatively the local surface of water corresponding to the ascending flow 207.

[0243] The aft planing surface 208 supposed to keep the required vertical position in order to provide proper position of the boat 201 and accordingly the required angle of incidence 206 of the forward surfaces 203, and to keep the required angle of incidence 212 relatively the local surface of water in order to generate the required lift, and in these terms the vertical and angular position of the aft planing surface 208 (represented in this diagram by the keel point of the leading edge 209 and the base plane 210) should correspond the local ascending flow 207.

[0244] To match the parameters of local flow 207 the aft cambered planing surface 208 in its center plane section positioned higher than the base planes 204 of the forward surfaces 203 by the height 213 of the ascending flow 207 above the base planes 204 at the location of the leading edge 209 of the center plane keel sections 211 and turned counter-clockwise (nose-dive) by the angle 214 of the ascending flow 207 at the location of the leading edge 209 of the center plane keel sections 211 relatively the level of undisturbed water surface W.

[0245] Thus, as a result, the base plane 210 of the aft cambered planing surface 208 positioned at the angle 215 relatively the base planes 204 of the forward surfaces 203, which negative angle 215 represents the combination of the angles 206, 214 and 212. That is: the negative angle 214 plus the difference between the positive angles 212 and 206 (angle 212 minus angle 206).

[0246] In a similar way, the vertical and angular positions of other longitudinal vertical sections of the aft planing surface 208 are determined in accordance with the rise and inclination of the ascending flow in these sections, which results in a certain spatial and angular arrangement of the sections and their base planes relative to the sections and base planes of the forward vortex generators 203 (as well as, accordingly, the aft planing surface as a whole relatively the surfaces 203) and, taking into account the shape of the surface of the ascending flow formed by the velocity field generated by the two counter-rotating parallel vortex cords, determines the configuration of the aft surface with gradually increasing deadrise angles and modules of negative angles of inclination of sections from the central plane outward in such a way that the half-planes of the aft surface are curved up and twisted down in a substantially hyperbolic manner.

[0247] Consequently, for the same center plane section 211 of the aft cambered planing surface 208 if skimming along the undisturbed water surface W, the vector of the dynamic lift force would be directed upward and somewhat backward (creating rearward directed horizontal projection responsible for the hydrodynamic drag).

[0248] However, as a part of the hydrodynamic system under consideration, to be conformant to the ascending flow 207 the section 211 and, so, the vector of the dynamic lift force will be turned counterclockwise (i.e., forward in the direction of movement of the boat) by the angle corresponding to the angle of elevation 214 of the ascending flow 207 at the location of the leading edge 209, which new position of the lift vector will affect, reduce and may be even change the sign of its projection onto the horizontal plane.

[0249] Similarly, the tilting of the dynamic lift vectors will occur in other sections of the aft planing surface.

[0250] Accordingly, the resulting lift vector of the aft planing surface 208 in general will tilt forward as well that will lead to reduction of the directed backwards (i.e., generating drag) projection of said lift vector onto the horizontal plane, while ultimately such tilting could even change the sign of this horizontal projection in the case of high hydrodynamic efficiency of the aft surface and high angles of slope of the ascending flow.

[0251] This reduction of said directed backwards horizontal projection (and, moreover, change of its sign) occurring on the aft planing surface could be considered as the appearance of an additional directed forward horizontal force (being similar to some additional thrust, although the resistance of the entire hydrodynamic system of the three planing surfaces, of course, could reduce but would remain effective) that will reduce drag and increase the hydrodynamic efficiency of the boat 201.

[0252] That is, in this way said aft planing surface 208 will actually recover a part of the energy spent by the forward planing surfaces 203 to disturb the incoming flow and to lift the water in the gap between the forward planing surfaces 203 above the level of undisturbed water surface W in the form of generation of the ascending flow 207.

[0253] FIG. 3 depicts a schematic diagram illustrating the bottom plan view of the boat according to some embodiments, where the boat 201 is provided with two swept back forward planing surfaces 203 represented by their profiled wetted areas being hatched in this diagram, which two forward planing surfaces 203 set apart both sides of the boat's center plane and form the gap with the width 301, and one aft planing surface 208 represented by its profiled wetted area being hatched in this diagram, while said aft planing surface 208 with the width 302 located at the center plane of the boat 201. Sections of the aft planing surface 208 by vertical longitudinal planes are positioned at the distance 304 aft from the forward planing surfaces measured along the length of the boat 201 up to the leading edges of sections of the aft planing surface 208 and represented in this diagram by section 305. This diagram assumes that the forward planing surfaces 203 are separated from the bottom of the boat 201 and the aft planing surface 208 is integrated into the aft part of the bottom of the boat 201, while the span of the aft surface 208 in the transverse direction is limited by deflectors 306.

[0254] The inner (facing the center plane of the boat 201 and each other) edges 303 of the forward planing surfaces 203 generate tip vortices of opposite rotation (relatively their axes arranged along the flow) eventually shedding from the edges 303 and surfaces 203, carried downstream by the flow and forming the core lines while turning the masses of water (around the vortices' core lines) in the gap channel between forward planing surfaces 203 up and producing a velocity field in the gap with a velocity component directed upwards, which creates an ascending flow downstream the planing surfaces 203, rising above the undisturbed water level and inclined to this level at some negative angle.

[0255] To ensure hydrodynamically favorable relative spatial and angular positions of the surfaces 203 and 208, as well as the configuration of the aft cambered planing surface 208 matching the ascending flow in order to use the ascending flow effect, each section by vertical longitudinal planes of the aft cambered planing surface 208 is arranged higher (lower in this upside-down position) than the base lines of the forward planing surfaces 203 by the height of the surface of ascending flow above the base lines of the forward planing surfaces 203 at the location of the leading edges of sections of the aft cambered planing surface 208, and the base lines of said sections of the aft surface 208 turned nose-dive (nose-up in this upside-down position) relatively the base lines of the forward planing surfaces by the angle corresponding the negative angle of slope of the surface of ascending flow at the location of the leading edges of sections of the aft cambered planing surface 208.

[0256] So that the angle between the base lines of each section of the aft 208 and forward 203 planing surfaces constitutes the sum of the negative angle of the slope of the surface of the ascending flow relatively the level of the undisturbed water surface at the location of this section of the aft planing surface 208 and the difference between the angle of incidence of the base line of the section of the aft planing surface 208 relatively the local surface of water corresponding to the surface of the ascending flow at the location of said section of the aft planing surface 208 and the angle of incidence of the base lines of the forward planing surfaces 203 relatively the level of the undisturbed water surface. Consequently, taking into consideration the shape of the surface of the ascending flow generated by two parallel along the flow counter-rotating vortex cords, in order to meet the above requirements for the hydrodynamically efficient configuration of the aft planing surface 208 conforming the ascending flow, angles of deadrise and moduli of negative (nose-dive) angles of inclination of base lines of sections of the aft planing surface 208 relatively the base lines of the forward planing surfaces should gradually increase along the span of the aft planing surface from the center plane of the system outwards resulting in half-planes of said aft planing surface being curved upwards and twisted downwards in a substantially hyperbolic manner.

[0257] In this case, the directed upward vector of the dynamic lift force of the aft cambered planing surface 208 will be turned forward in the direction of movement of the boat and the associated with drag projection of said lift vector onto the horizontal plane will reduce or even will change sign (will change direction to the opposite), which resulting reduced or even opposite-directed drag-determining projection will be equivalent to the appearance of an additional forward-looking component of the horizontal force, similar to some additional thrust that will reduce drag and increase the hydrodynamic efficiency of the boat 201.

[0258] That is, in this way said aft planing surface 208 will actually recover a part of the energy spent by the forward planing surfaces 203 to disturb the incoming water flow and to raise the water in the gap between the forward planing surfaces 203 above the level of undisturbed water surface in the form of generation of the ascending flow.

[0259] In this embodiment span-limiting deflectors 306 of the aft planing surface 208 increase hydrodynamic pressure and lift of this planing surface, reduce inductive drag (which is equivalent to increase in aspect ratio of these dynamic lift surfaces) and this way further improve efficiency of this hydrodynamic system and the boat 201 as a whole.

[0260] In said hydrodynamic system the ratio of the width 301 to the width 302 can be optimized for specific parameters of motion and design of the boat 201 taking into consideration the diameter of the cores of the vortices generated by the planing surfaces 203 at the edges 303 and the transverse deviation of the vortices' core lines downstream the forward surfaces 203.

[0261] As for size 304, taking into account the wave nature of the ascending flow, in order to maximize the use of the effect of ascending flow, the aft planing surface 208 should be preferably located not far aft from the forward planing surfaces 203, within the range of high angles of slope of the ascending flow, and anyway not further than the length of the quarter of the wave of the ascending flow, but not too close to the surfaces 203, keeping in mind, first of all, the dynamic stability of the boat 201 in the vertical longitudinal plane.

[0262] FIG. 4 depicts a schematic diagram illustrating the front elevation view of a boat according to some embodiments and basically corresponding to the embodiment of the FIG. 3, where a boat 201 provided with two forward vortex-generating cambered planing surfaces 203 with their inner edges 303 and outer side deflectors 401, which planing surfaces are separated from the bottom of the boat 201, connected structurally with the bottom by means of struts 202 and are cantilevered at the lower ends of the struts 202, and the aft cambered planing surface 208 being integrated into the aft part of the bottom of the boat 201 and limited spanwise by deflectors 306.

[0263] The forward planing surfaces 203 on facing each other inner edges 303 generate vortices VX of opposite rotation with the right vortex rotating clockwise and the left one rotating counterclockwise.

[0264] Said vortices VX produce a flow velocity field in the gap between and downstream the planing surfaces 203 with a velocity component directed upwards, which creates an ascending flow downstream these planing surfaces 203, rising above the undisturbed water level and inclined at some negative angle to this level.

[0265] To ensure hydrodynamically favorable relative spatial and angular positions of the surfaces 203 and 208, as well as the configuration of the aft cambered planing surface 208 matching the ascending flow in order to use the ascending flow effect, each section by vertical longitudinal planes of the aft cambered planing surface 208 is arranged higher than the base lines of the forward planing surfaces 203 by the height of the surface of ascending flow above the base lines of the forward planing surfaces 203 at the location of the leading edges of sections of the aft cambered planing surface 208, and the base lines of said sections of the aft surface 208 turned nose-dive relatively the base lines of the forward planing surfaces by the angle corresponding the negative angle of slope of the surface of ascending flow at the location of the leading edges of sections of the aft cambered planing surface 208.

[0266] So that the angle between the base lines of each section of the aft 208 and forward 203 planing surfaces constitutes the sum of the negative angle of the slope of the surface of the ascending flow relatively the level of the undisturbed water surface at the location of this section of the aft planing surface 208 and the difference between the angle of incidence of the base line of the section of the aft planing surface 208 relatively the local surface of water corresponding to the surface of the ascending flow at the location of said section of the aft planing surface 208 and the angle of incidence of the base lines of the forward planing surfaces 203 relatively the level of the undisturbed water surface.

[0267] Consequently, taking into consideration the shape of the surface of the ascending flow generated by two parallel along the flow counter-rotating vortex cords, in order to meet the above requirements for the hydrodynamically efficient configuration of the aft planing surface 208 conforming the ascending flow, the angles of deadrise and moduli of negative (nose-dive) angles of inclination of base lines of sections of the aft planing surface 208 relatively the base lines of the forward planing surfaces should gradually increase along the span of the aft planing surface from the center plane of the system outwards resulting in half-planes of said aft planing surface being curved upwards and twisted downwards in a substantially hyperbolic manner.

[0268] In this case, the directed upward vector of the dynamic lift force of the aft cambered planing surface 208 will be turned forward in the direction of movement of the boat and the associated with drag projection of said lift vector onto the horizontal plane will reduce or even will change sign (will change direction to the opposite), which resulting reduced or even opposite-directed drag-determining projection will be equivalent to the appearance of an additional forward-looking component of the horizontal force, similar to some additional thrust that will reduce drag and increase the hydrodynamic efficiency of the boat 201.

[0269] That is, in this way said aft planing surface 208 will actually recover a part of the energy spent by the forward planing surfaces 203 to disturb the incoming water flow and to raise the water in the gap between the forward planing surfaces 203 above the level of undisturbed water surface in the form of generation of the ascending flow.

[0270] In this embodiment span-limiting deflectors 306 of the aft planing surface 208 and the deflectors 401 at the outer ends of the forward vortices-generating planing surfaces 203 increase hydrodynamic pressure and lift of these planing surfaces (while corresponding raise in the lift coefficient of the forward planing surfaces 203 will result in a higher angle of slope of the ascending flow), reduce inductive drag (which is equivalent to increase in aspect ratio of these dynamic lift surfaces) and this way further improve efficiency of this hydrodynamic system and the boat 201 as a whole.

[0271] Through separating the forward planing surfaces 203 from the bottom of the boat 201 the described embodiment combines the hydrodynamic design of the present invention with a conventional single-keel configuration of the bow part of boat hull, while the bottom surfaces of the boat at its bow part can be made with much higher angle of deadrise indicated by the dotted line 402 and ensure much sharper entry that should considerably upgrade seaworthiness of the boat, not sacrificing lift and hydrodynamic efficiency (provided by the hydrodynamic system employing the ascending flow effect and configured according to provisions of this invention).

[0272] The aft planing surface 208 in this embodiment does not require manufacturing as a separate unit and in the case of use of composite structural material (fiber reinforced plastics, e.g.) can be laminated at once altogether with the hull of the boat 201.

[0273] FIG. 5 is a schematic diagram that illustrates the perspective front bottom view of a boat according to some embodiments and basically corresponding to the embodiments of the FIG. 3 and FIG. 4, where the boat is provided with the hydrodynamic system comprising two forward vortex-generating cambered planing surfaces being separated from the bottom of the boat and one aft planing surface being integrated into boat's bottom.

[0274] In this embodiment the boat 201 is provided with two forward vortex-generating cambered planing surfaces 203 connected structurally with the bottom by means of struts 202 and extend inward from the lower ends of the struts 202.

[0275] The port and starboard cambered planing surfaces 203 set apart both sides of the boat's center plane and generate at their inner edges 303 two counter-rotating tip vortices, which create the ascending flow in the gap between said inner edges and further aft downstream the flow.

[0276] The boat 201 is provided also with the third aft cambered planing surface 208 arranged in the center plane of the boat 201 and integrated into boat's bottom at some distance aft from the forward planing surfaces 203.

[0277] To ensure hydrodynamically favorable relative spatial and angular positions of the surfaces 203 and 208, as well as the configuration of the aft cambered planing surface 208 matching the ascending flow in order to use the ascending flow effect, each section by vertical longitudinal planes of the aft cambered planing surface 208 is arranged higher (lower in this upside-down position) than the base lines of the forward planing surfaces 203 by the height of the surface of ascending flow above the base lines of the forward planing surfaces 203 at the location of the leading edges 209 of sections of the aft cambered planing surface 208, and the base lines of said sections of the aft surface 208 turned nose-dive (nose-up in this upside-down position) relatively the base lines of the forward planing surfaces by the angle corresponding the negative angle of slope of the surface of ascending flow at the location of the leading edges of sections of the aft cambered planing surface 208.

[0278] So that the angle between the base lines of the sections of the aft 208 and forward 203 planing surfaces constitutes the sum of the negative angle of the slope of the surface of the ascending flow relatively the level of the undisturbed water surface at the location of each section of the aft planing surface 208 and the difference between the angle of incidence of the base line of the section of the aft planing surface 208 relatively the local surface of water corresponding to the surface of the ascending flow at the location of said section of the aft planing surface 208 and the angle of incidence of the base lines of the forward planing surfaces 203 relatively the level of the undisturbed water surface.

[0279] Consequently, taking into consideration the shape of the surface of the ascending flow generated by two parallel along the flow counter-rotating vortex cords, in order to meet the above requirements for the hydrodynamically efficient configuration of the aft planing surface 208 conforming the ascending flow, the angles of deadrise and moduli of negative (nose-dive) angles of inclination of base lines of sections of the aft planing surface 208 relatively the base lines of the forward planing surfaces should gradually increase along the span of the aft planing surface from the center plane of the system outwards resulting in half-planes of said aft planing surface being curved upwards and twisted downwards in a substantially hyperbolic manner.

[0280] In this case, the directed upward vector of the dynamic lift force of the aft cambered planing surface 208 will be turned forward in the direction of movement of the boat and the associated with drag projection of said lift vector onto the horizontal plane will reduce or even will change sign (will change direction to the opposite), which resulting reduced or even opposite-directed drag-determining projection will be equivalent to the appearance of an additional forward-looking component of the horizontal force, similar to some additional thrust that will reduce drag and increase the hydrodynamic efficiency of the boat 201.

[0281] That is, in this way said aft planing surface 208 will actually recover a part of the energy spent by the forward planing surfaces 203 to disturb the incoming water flow and to raise the water in the gap between the forward planing surfaces 203 above the level of undisturbed water surface in the form of generation of the ascending flow.

[0282] In this embodiment span-limiting deflectors 306 of the aft planing surface 208 and the deflectors 401 at the outer sections of the forward vortices-generating planing surfaces 203 increase hydrodynamic pressure and lift of these planing surfaces (while corresponding raise in the lift coefficient of the forward planing surfaces 203 will result in a higher angle of slope of the ascending flow), reduce inductive drag (which is equivalent to increase in aspect ratio of these dynamic lift surfaces) and this way further improve efficiency of this hydrodynamic system and the boat 201 as a whole.

[0283] The aft planing surface 208 in this embodiment does not require manufacturing as a separate unit and in the case of use of composite structural material (fiber reinforced plastics, e.g.) can be laminated at once altogether with the hull of the boat 201.

[0284] FIG. 6 depicts a schematic diagram illustrating the front elevation view of a boat according to some embodiments, where the boat 201 provided with three cambered planing surfaces being separated from the bottom of the boat 201 and comprising: two forward vortex-generating cambered planing surfaces 203 with their inner edges 303 and outer side deflectors 401, which planing surfaces are connected structurally with the bottom by means of struts 202 and extend inward from the lower ends of the struts 202, and the aft cambered planing surface 208 representing a separated from the bottom unit. The aft surface 208 is provided with end deflectors 306 and structurally connected to the bottom of the boat 201 by means of the keel strut or flange 601 and side struts 602, while designation 1-1 indicates the along the flow section of the forward planing surfaces 203.

[0285] Like in previously mentioned embodiments, the inner edges 303 of the forward planing surfaces 203 generate vortices VX of opposite rotation producing a velocity field in the gap between planing surfaces and further aft with a velocity component directed upwards, which velocity field creates an ascending flow downstream these forward planing surfaces, rising above the undisturbed water level and inclined at some negative angle of elevation to this level, while vertical longitudinal sections of the separated aft planing surface 208 made conformal to the shape of the surface of the ascending flow and have the angular position taking into account the negative angle of inclination of the surface of the upward flow, which determines the spatial position of sections of the aft surface 208 above the base lines of the forward surfaces 203, the inclination of the base lines of the sections of the aft surface 208 nose-dive relative to the base lines of the forward surfaces 203 at the angles of inclination of the ascending flow, and the configuration of the aft surface 208 with gradually increasing from the central plane outward deadrise angles and moduli of negative angles of inclination of sections resulting in its half-planes curved upward and twisted downward in a substantially hyperbolic manner.

[0286] Through utilization of the above features of the ascending flow, the resulting configuration as well as spatial and angular position of the aft planing surface 208 relatively the forward planing surfaces 203 reduces the hydrodynamic drag of this system of the three planing surfaces and increases the efficiency of the boat 201.

[0287] In this embodiment span-limiting deflectors 306 of the aft planing surface 208 and the deflectors 401 at the outer sections of the forward vortices-generating planing surfaces 203 increase hydrodynamic pressure and lift of these planing surfaces (while corresponding raise in the lift coefficient of the forward planing surfaces 203 will result in a higher angle of slope of the ascending flow), reduce inductive drag (which is equivalent to increase in aspect ratio of these dynamic lift surfaces) and this way further improve efficiency of this hydrodynamic system and the boat 201 as a whole.

[0288] By means of separation of the hydrodynamic system featuring the two forward cambered planing surfaces 203 and one aft cambered planing surface 208 from the bottom of the boat 201, in this embodiment the bottom surfaces of the boat 201 are independent of the geometric shapes that are optimal for planing surfaces 203 and 208 and provided with much higher angle of deadrise (much higher than the angle of deadrise of planing surfaces) and this way ensure much sharper entry that should considerably upgrade seaworthiness of the boat 201 not sacrificing lift and hydrodynamic efficiency ensured by the spatial and angular arrangement and configuration of separated planing surfaces 203 and 208 reproducing the provisions of this invention, while distancing the planing surfaces from the bottom of the boat by means of hydrofoil-style struts 202, 601 and 602 brings additional advantages in terms of improvement in seaworthiness.

[0289] At the same time, taking into account that the struts of this embodiment support planing surfaces skimming along the surface of water, said hydrofoil-style struts 202, 601 and 602 made much shorter that results in less bulky design and much shallow draft in comparison with conventional submerged hydrofoils in the displacement mode, not to mention the negligible draft of planing surfaces in comparison with hydrofoils in the operational high-speed mode of motion.

[0290] This circumstance is added to the absence of cavitation as the main advantage of this hydrodynamic planing system over hydrofoils, which feature (in contrast to hydrofoils) eliminates all speed restrictions.

[0291] FIG. 7 is a schematic diagram that illustrates the perspective front bottom view of a boat according to some embodiments and basically corresponding to the embodiment of the FIG. 6, where the boat is provided with the hydrodynamic system featuring three cambered planing surfaces separated from the bottom of the boat.

[0292] In this embodiment the boat 201 is provided with two forward vortex-generating cambered planing surfaces 203 with their inner edges 303 and outer side deflectors 401, connected structurally with the bottom by means of struts 202, which surfaces 203 extend inward from the lower ends of the struts 202, while in order to strengthen the forward vortex-generating planes the inner tips of the surfaces 203 are supported here with additional struts 701.

[0293] The port and starboard cambered planing surfaces 203 set apart both sides of the boat's center plane and generate at their inner edges 303 two counter-rotating tip vortices, which create the ascending flow in the gap between said inner edges and further aft downstream the flow.

[0294] The boat 201 is provided also with the third separated aft cambered planing surface 208 arranged in the center plane of the boat 201 at some distance aft from the forward planing surfaces 203 and below the bottom of the boat 201 (above the bottom in this upside-down view), which aft cambered planing surface 208 features end deflectors 306 and structurally connected to the bottom of the boat 201 by means of the keel strut 601 and side struts 602.

[0295] Like in previously mentioned embodiments, vertical longitudinal sections of the separated aft planing surface 208 made conformal to the shape of the surface of the ascending flow and have the angular position taking into account the negative angle of inclination of the surface of the upward flow, which determines the spatial position of sections of the aft surface 208 above the base lines of the forward surfaces 203, the inclination of the base lines of the sections of the aft surface 208 nose-dive relative to the base lines of the forward surfaces 203 at the angles of inclination of the ascending flow, and the configuration of the aft surface 208 with gradually increasing from the central plane outward deadrise angles and moduli of negative angles of inclination of sections resulting in its half-planes curved upward and twisted downward in a substantially hyperbolic manner.

[0296] Through utilization of the above features of the ascending flow, the resulting configuration as well as spatial and angular position of the aft planing surface 208 relatively the forward planing surfaces 203 reduces the hydrodynamic drag of this system of the three planing surfaces and increases the efficiency of the boat 201.

[0297] By means of separation of the hydrodynamic system featuring three cambered planing surfaces 203 and 208 from the bottom of the boat 201, in this embodiment the bottom surfaces of the boat 201 are independent of the geometric shapes that are optimal for planing surfaces 203 and 208 and provided with much higher angle of deadrise (much higher than the angle of deadrise of planing surfaces) and this way ensure much sharper entry that should considerably upgrade seaworthiness of the boat 201 not sacrificing lift and hydrodynamic efficiency ensured by the spatial and angular arrangement and configuration of separated planing surfaces 203 and 208 reproducing the provisions of this invention, while distancing the planing surfaces from the bottom of the boat by means of hydrofoil-style struts 202, 601, 602 and 701 brings additional advantages in terms of improvement in seaworthiness.

[0298] At the same time, taking into account that the struts support planing surfaces skimming along the surface of water, said hydrofoil-style struts 202, 601, 602 and 701 made much shorter that results in less bulky design and much shallow draft in comparison with conventional submerged hydrofoils in the displacement mode, not to mention the negligible draft of planing surfaces in comparison with hydrofoils in the operational high-speed mode of motion.

[0299] This circumstance is added to the absence of cavitation as the main advantage of this hydrodynamic planing system over hydrofoils, which feature (in contrast to hydrofoils) eliminates all speed restrictions.

[0300] FIG. 8 depicts a schematic diagram illustrating one of possible embodiments of the normal to the plane along the flow section of the separated from the boat's bottom plane associated with the planing surface 203 and corresponding to the designation 1-1 of the embodiment of the FIG. 6.

[0301] In this drawing the section of the plane has its bottom part extending from the leading edge 801 up to the trailing edge 802, while the aft portion of this bottom is made concaved and represents the cambered planing surface 203.

[0302] As one of embodiments the planing surface 203 can reproduce a camber based on the Virgil Johnson three-term curve that was successfully applied to real planing surfaces in the past.

[0303] In operational mode of motion the cambered planing surface 203 skims along the surface of water and generates dynamic lift that supports the boat 201, and the planing surface 203 is the only surface of such section that supposed to contact the water at the operational speed of motion. Thus, basically, to fulfill its duty of dynamic support of the boat at the operational speed the lifting surface of this section should be limited by the bottom surface 203.

[0304] The embodiment shown in the FIG. 8 provided also with the streamlined convex upper surfaces 803 being similar to upper surfaces of hydrofoils.

[0305] The embodiment featuring the streamlined convex upper surfaces 803 can produce a double positive effect: [0306] 1. At moderate speed of the boat corresponding transitional mode of motion (from floating displacement mode to purely planing mode) when the separated planing surfaces supposed to be completely submerged in water, the upper streamlined convex surfaces 803 is in contact with water and generates negative pressure resulting in additional hydrodynamic lift the same way as upper convex surfaces of hydrofoils that facilitates acceleration and take-off of the boat up to the transition to the purely planing mode. During motion at the operational speed in the purely planing mode said streamlined convex upper surfaces 803 will be excluded from generation of lift as they will be positioned above the level of water, will not contact the water (washed only by air and without any risk of cavitation) and will not affect operation of the planing surfaces. [0307] 2. Providing the separated planing surfaces with the streamlined convex upper surfaces 803 makes them stronger structurally: The streamlined convex upper surface 803 increases the structural height of the section (in fact without increase in the drag) and, correspondingly, the moment of inertia and the moment of structural resistance of the section of planing surface that reduces bending stresses in the material of the separated planing surface made in the form of a cantilever structure, e.g.

[0308] This embodiment of the section shown in the FIG. 8 is provided also with flat portion 804 of the bottom surface between the leading edge 801 and the leading edge of the profiled portion of bottom of the section corresponding to the cambered planing surface 203, while this flat portion 804 may coincide with the hydrodynamic base plane of the cambered planing surface 203 that could be found useful to facilitate transition from the hydrofoil-assisted mode to the highly efficient purely planing one featuring wetted area being limited by the cambered planing surface 203.

[0309] FIG. 9 is a schematic diagram that illustrates the perspective aft bottom view of a boat employing the hydrodynamic system of three cambered planing surfaces arranged following this invention and integrated into boat's bottom according to some embodiments.

[0310] In this embodiment the boat 201 is provided with two sponsons 901 protruding downwards (upwards in this upside-down view) from the forward part of bottom of said boat and transversely spaced apart both sides of the center plane of said boat, while vortex-generating swept back cambered planing surfaces 203 with their inner edges 303 and outer side deflectors 401 are integrated into the aft bottom part of sponsons 901 and extend outwardly relative to the keel lines of the sponsons 901.

[0311] As bottom portions of the sponsons 901, the port and starboard cambered planing surfaces 203 spaced apart both sides of the boat's center plane generate at their inner edges 303 two counter-rotating tip vortices, which create the ascending flow in the gap between said inner edges and further aft downstream the flow.

[0312] The boat 201 is provided also with the third aft cambered planing surface 208 with deflectors 306 at the ends of its span, which surface 208 is arranged in the center plane of the boat 201 and integrated into boat's bottom at some distance aft from the forward planing surfaces 203.

[0313] Vertical longitudinal sections of the integrated into bottom aft planing surface 208 made conformal to the shape of the surface of the ascending flow and have the angular position taking into account the negative angle of inclination of the surface of the ascending flow, which determines the spatial position of sections of the aft surface 208 above the base lines of sections of the forward surfaces 203, the inclination of the base lines of the sections of the aft surface 208 nose-dive relative to the base lines of the forward surfaces 203 at the angles of inclination of the ascending flow, and the configuration of the aft surface 208 with gradually increasing from the central plane outward deadrise angles and moduli of negative angles of inclination of sections resulting in its half-planes curved upward and twisted downward in a substantially hyperbolic manner.

[0314] Through utilization of the above features of the ascending flow, the resulting configuration as well as spatial and angular position of the aft planing surface 208 relatively the forward planing surfaces 203 reduces the hydrodynamic drag of this system of the three planing surfaces and increases the efficiency of the boat 201.

[0315] In this embodiment span-limiting deflectors 306 of the aft planing surface 208 and the deflectors 401 at the outer sections of the forward vortices-generating planing surfaces 203 increase hydrodynamic pressure and lift of these planing surfaces (while corresponding raise in the lift coefficient of the forward planing surfaces 203 will result in a higher angle of slope of the ascending flow), reduce inductive drag (which is equivalent to increase in aspect ratio of these dynamic lift surfaces) and this way further improve efficiency of this hydrodynamic system and the boat 201 as a whole.

[0316] The integration of the planing surfaces 203 and 208 of this embodiment into the bottom surfaces of the boat 201 (namely, the aft portions of the sponson bottoms and the bottom of the main boat hull) allows the profiled planing surfaces 203 and 208 to be laminated and formed in one mold at once altogether with the boat hull, which can significantly simplify manufacturing of boats employing the hydrodynamic design of this invention.

[0317] FIG. 10 depicts a schematic diagram illustrating the front elevation view of a boat according to some embodiments, where the boat 201 is provided at its bottom part with three streamlined floats comprising two forward floats 1001 spaced apart relatively the center plane of the boat 201 and one aft float 1002 arranged at the center plane of the boat 201, while these floats support the boat 201 by Archimedean forces and keep it above the water level 1003 in the displacement mode when not moving or at low speed.

[0318] The boat 201 employs also the hydrodynamic system of three separated cambered planing surfaces according to this invention and comprising the two forward vortex- and ascending flow-generating planing surfaces 203 and the aft planing surface 208, which surfaces mounted on the bottom ends of the streamlined floats 1001 and 1002 correspondingly, and provided with convex upper surfaces 803.

[0319] Following provisions of this invention the planing surfaces 203 and 208 arranged spatially and angularly, and the aft planing surface 208 configured the way presupposing utilization of the ascending flow effect.

[0320] Taking into consideration the above, the boat 201 of this embodiment might have minimal hydrodynamic resistance and maximum efficiency in three consecutive modes of motion covering the full speed range of this boat: [0321] 1. The minimum resistance and maximum efficiency in the displacement mode of motion at low Froude numbers ensured due to the low-drag movement in water of the only immersed streamlined floats 1001 and 1002. [0322] 2. The minimum resistance and maximum efficiency in the transitional mode provided by high lift and efficiency of separated planes 203 and 208 with convex upper surfaces 803 being submerged in this mode and operating as hydrofoils (while moderate transitional speeds do not cause the problem of cavitation). [0323] 3. The principal operational high-speed and highly efficient mode of motion when the boat 201 is supported exclusively by cambered planing bottoms of two forward planing surfaces 203 and one aft planing surface 208, which high efficiency is ensured by the use of the ascending flow effect, not having any speed limits caused by cavitation (since use of only planing bottom surfaces 203 and 208 generating only positive hydrodynamic pressures). In this principal operational mode the streamlined floats 1001 and 1002 as well as the convex upper surfaces 803 of the separated cambered planing surfaces 203 and 208 are excluded from generation of any lift. They supposed to be out of any contact with water and they do not affect the operation of planing surfaces 203 and 208. This way there could be achieved a smooth transition from low-speed modes of operation to high-speed ones and obtained gently sloping resistance vs. speed curve with low hump of a drag that in its turn should result in reduced power requirements, lower cost of the powerplant, longer range, etc.

[0324] In addition, supporting the hull of the boat 201 above the water level 1003 in the displacement mode by said streamlined floats 1001 and 1002 with a small waterline area will make the boat 201 less sensitive to wave impacts, which design can significantly suppress pitching and rolling of the boat 201 (that moreover should be vastly damped by surfaces of submerged separated planes 203 and 208) and substantially ameliorate the comfort of staying aboard.

[0325] To further facilitate take off of the boat 201 and enhance stability in the operational mode of motion, the bottom ends of the streamlined floats 1001 and 1002 can also be provided with supplementary hydrofoils or additional take-off planing surfaces 1004, which supposed to be out of contact with water during high-speed operation under low and moderate Sea State conditions.

[0326] In this embodiment the span of the aft planing surface 208 is limited by deflectors 306 and the forward vortices-generating planing surfaces 203 are provided with end plates 1005, which design features increase hydrodynamic pressure and lift of these planing surfaces (while corresponding raise in the lift coefficient of the forward planing surfaces 203 will result in a higher angle of slope of the ascending flow), reduce inductive drag (which is equivalent to increase in aspect ratio of these dynamic lift surfaces) and this way further improve efficiency of this hydrodynamic system and the boat 201 as a whole.

[0327] FIG. 11 depicts a schematic diagram that illustrates the rear perspective view of bottom of a boat (shown upside-down), which is basically close to the embodiment of the diagram 10, where a boat 201 is provided at its bottom part with three streamlined floats comprising two forward floats 1001 spaced apart relatively the center plane of the boat 201 and one aft float 1002 arranged at the center plane of the boat 201, while in this diagram the forward floats 1001 are structurally connected to the hull by means of struts 202.

[0328] The hydrodynamic system of three separated cambered planing surfaces according to this invention and comprising the two forward vortexand ascending flowgenerating planing surfaces 203 and the aft planing surface 208 are mounted on the bottom ends of the streamlined floats 1001 and 1002 correspondingly.

[0329] The combination of the low-drag streamlined floats supporting the boat 201 in the displacement mode with the hydrodynamic system of the three cambered planing surfaces 203 and 208 employing the ascending flow effect following this invention and serving as the dynamic support devices for the highly efficient high-speed operation (and moreover provided with not shown here hydrofoil-like upper surfaces for easier take-off), minimizes drag and ensures high efficiency of the boat 201 in all three consecutive modes of operation of the boat 201: low-speed floating, transitional mode and the principal high-speed operation.

[0330] To facilitate take off of the boat 201 and coming to the operational high-speed planing mode, as well as to enhance stability in the operational mode of motion, the bottom ends of the streamlined floats 1001 and 1002 provided also with supplementary hydrofoils or additional take-off planing surfaces 1004, which supposed to be out of contact with water during high-speed operation under low and moderate Sea State conditions.

[0331] Similarly to the embodiment of the FIG. 10, the span of the aft planing surface 208 is limited by deflectors 306 and the forward vortices-generating planing surfaces 203 are provided with end plates 1005, which design features increase hydrodynamic pressure and lift of these planing surfaces (while corresponding raise in the lift coefficient of the forward planing surfaces 203 will result in a higher angle of slope of the ascending flow), reduce inductive drag (which is equivalent to increase in aspect ratio of these dynamic lift surfaces) and this way further improve efficiency of this hydrodynamic system and the boat 201 as a whole.

[0332] Suspension of the front floats 1001 under the bottom of the boat 201 by means of struts 202 forms a gap between the float 1001 and the hull of boat 201 and prevents slamming in the area where the internal surfaces of the floats 1001 attach the bottom in the embodiment shown in Diagram 10. In this way, this embodiment moderates the impact of waves, i.e., reduce structural loads and accelerations and thereby soften the ride in waves and increase the comfort of staying aboard during riding under high Sea States.

[0333] The penetration through large waves is further improved by the elongated streamlined cross sections of struts 202 oriented along the inclined flow created as a result of the interaction of the wave and the bottom surfaces of the boat 201, which oblique position of sections presupposes that their leading edges are located closer to the center plane of the boat 201 than the trailing edges.

[0334] The cross sections of struts 202 are provided also with a profile and angle of incidence ensuring, when interacting with a wave, generation of a pulling hydrodynamic force (i.e., some additional thrust), which further facilitates riding under rough sea conditions.

[0335] FIG. 12 depicts a schematic diagram illustrating the front elevation view of a boat of catamaran configuration according to some embodiments of this invention, where the catamaran boat 201 (shown in the displacement mode corresponding to the waterline 1003) has two hulls 1201 and equipped, in accordance with this invention, with the hydrodynamic system consisting of three separated cambered planing surfaces 203 and 208 with convex hydrofoil-like upper surfaces 803. Each of the two forward vortex-generating surfaces 203 mounted under the bottom of corresponding hull 1201 at its forward part and the aft separated cambered planing surface 208 positioned between the catamaran hulls 1201 in the aft part of the catamaran boat 201 and supported by the center plane strut 1202.

[0336] In the displacement mode and at low speed of motion the catamaran boat 201 is supported predominantly by Archimedean forces of hulls 1201 which keep the boat 201 floating at the water level 1003.

[0337] At higher speed of motion corresponding to the transitional mode, the separated cambered planing surfaces 203 and 208 start to generate some dynamic lift assisted by the lift produced by their still submerged hydrofoil-like convex upper surfaces 803.

[0338] At the principal high-speed operational mode of motion the hulls 1201 as well as the convex upper surfaces 803 are positioned above the water level and the catamaran boat 201 is supported exclusively by the dynamic lift generated by cambered bottoms of planing surfaces 203 and 208 arranged following the hydrodynamic design of this invention and exploiting the effect of the ascending flow generated by the forward planing surfaces 203 by means of special position and configuration of the aft planing surface 208, and ensuring this way low drag and high efficiency of the catamaran boat 201.

[0339] Endowing the dynamic support function with only separate planing surfaces 203 and 208 makes it possible to provide the hulls 1201 with very sharp formations that mitigates wave impacts and favorably affects the seaworthiness of the catamaran boat 201.

[0340] The outer tips of the aft planing surface 208 fastened on the inner surfaces of the catamaran hulls 1201. This completely stops the flow of water over the tip edges of the aft planing surface 208, eliminates tip losses and increases the efficiency of both the aft planing surface 208 and the catamaran boat 201 as a whole. In addition, the attachment of the outer tips of the aft planing surface 208 to the hulls 1201 increases the strength of this design as a whole.

[0341] To facilitate take-off of the catamaran boat 201 and enhance stability in the operational mode of motion, the lower bottom ends of the hulls 1201 provided with supplementary hydrofoils or additional take-off planing surfaces 1004, which supposed to be out of contact with water during high-speed operation under low and moderate Sea State conditions.

[0342] The forward vortices-generating planing surfaces 203 are provided with end plates 1005 and the span of the aft planing surface 208 is limited by deflectors 306, which design features (in addition to attaching the outer tips of the aft planing surface 208 to hulls 1201) increase hydrodynamic pressure and lift of these planing surfaces (while corresponding raise in the lift coefficient of the forward planing surfaces 203 will result in a higher angle of slope of the ascending flow), reduce inductive drag (which is equivalent to increase in aspect ratio of these dynamic lift surfaces) and this way further improve efficiency of this hydrodynamic system and the catamaran boat 201 as a whole.

[0343] FIG. 13 depicts a schematic diagram illustrating the front elevation view of a boat of catamaran configuration according to some embodiments and basically corresponding to the embodiment of the FIG. 12, where the catamaran boat 201 (shown in the displacement mode corresponding to the waterline 1003) has two hulls 1201 and equipped, in accordance with this invention, with the hydrodynamic system consisting of three separated cambered planing surfaces 203 and 208 with their end plates 1005, deflectors 306 and convex hydrofoil-like upper surfaces 803. Each of the two forward vortex-generating cambered surfaces 203 mounted on the bottom of corresponding hull 1201 at its forward part and the aft separated dihedral cambered planing surface 208 positioned between the catamaran hulls 1201 in the aft part of the catamaran boat 201 and supported by the strut 1202.

[0344] In this embodiment semi-submerged counter-rotating propulsion propellers 1301 with longitudinal axes and directions of rotation 1302 mounted on the inner tips and downstream of forward planing surfaces 203, so that the direction of rotation of the right-hand propeller is clockwise and the left one is counterclockwise when viewed from the front, while the axes of rotation of propellers 1301 are basically coaxial with the axes of the cords of vortices generated by the forward planing surfaces 203.

[0345] In high-speed operational mode, rotation of propellers 1301 corresponding directions 1302 leads to an additional upward component of the flow velocity vector in the gap between the forward planing surfaces 203, which upward component will increase the angle of slope of the ascending flow further downstream, resulting in the sections of the aft planing surface 208 tilted at a larger negative (nose-dive) angle, and thereby reduce drag and increase the hydrodynamic efficiency of the catamaran boat 201.

[0346] To facilitate take-off and the transitional mode of the catamaran boat 201 and enhance stability in the operational mode of motion, the bottom ends of the hulls 1201 provided with supplementary hydrofoils or additional take-off planing surfaces 1004, which supposed to be out of contact with water during high-speed operation under low and moderate Sea State conditions.

[0347] FIG. 14 depicts a schematic diagram illustrating the bottom plan view of the boat of catamaran configuration according to some embodiments and basically corresponding to the embodiment of the FIG. 13, where the boat 201 has two hulls 1201 and equipped, in accordance with this invention, with the hydrodynamic system consisting of three separated cambered planing surfaces 203 and 208. Each of the two forward vortex-generating cambered surfaces 203 mounted on the bottom of corresponding hull 1201 at its forward part and the aft separated dihedral cambered planing surface 208 positioned between the catamaran hulls 1201 in the aft part of the catamaran boat 201.

[0348] In this embodiment counter-rotating propulsion propellers 1301 mounted on the tips of the inner vortices-shedding edges and positioned downstream of forward planing surfaces 203, so that the axes of rotation of propellers 1301 are basically coaxial with the axes of the cords of shed vortices.

[0349] In high-speed operational mode, rotation of propellers 1301 leads to an additional upward component of the flow velocity vector in the gap between the forward planing surfaces 203, which upward component will increase the angle of slope of the ascending flow further downstream, resulting in the sections of the aft planing surface 208, to be conformal to the ascending flow, shifted vertically against the base lines of the forward planing surfaces 203 and tilted at a larger negative (nose-dive) angle, and thereby reduce drag and increase the hydrodynamic efficiency of the catamaran boat 201.

[0350] To facilitate take-off and the transitional mode of the catamaran boat 201 and enhance stability in the operational mode of motion, the bottom ends of the hulls 1201 provided with supplementary hydrofoils or additional take-off planing surfaces 1004, which supposed to be out of contact with water during high-speed operation under low and moderate Sea State conditions.

[0351] FIG. 15 depicts a schematic diagram illustrating the bottom plan view of the boat of catamaran configuration according to some embodiments, where the catamaran boat 201 has two hulls 1201 and equipped, in accordance with this invention, with the hydrodynamic system consisting of three separated cambered planing surfaces 203 and 208. Each of the two forward vortex-generating cambered surfaces 203 mounted on the bottom of corresponding hull 1201 at its forward part and the aft separated dihedral cambered planing surface 208 positioned between the catamaran hulls 1201 in the aft part of the catamaran boat 201.

[0352] In this embodiment counter-rotating propulsion propellers 1301 are supported by struts, brackets or propulsion drives 1501 and positioned between the forward vortex-generating surfaces 203 and aft planing surface 208 along the length of the boat in the wakes of tip vortices shedding from the edges 303 of forward surfaces 203, so that the axes of rotation of propulsion propellers 1301 basically coaxial the axes of the cords of shed tip vortices of the forward surfaces 203.

[0353] In high-speed operational mode, rotation of propellers 1301 leads to an additional upward component of the flow velocity vector in the gap between the forward planing surfaces 203, which upward component will increase the angle of slope of the ascending flow further downstream, resulting in the sections of the aft planing surface 208, to be conformal to the ascending flow, shifted vertically against the base lines of the forward planing surfaces 203 and arrange at a larger negative (nose-dive) angle, and thereby reduce drag and increase the hydrodynamic efficiency of the catamaran boat 201.

[0354] To facilitate take off and the transitional mode of the catamaran boat 201 and enhance stability in the operational mode of motion, the bottom ends of the hulls 1201 provided with supplementary hydrofoils or additional take-off planing surfaces 1004, which supposed to be out of contact with water during high-speed operation under low and moderate Sea State conditions.

[0355] FIG. 16 depicts a schematic diagram illustrating the front elevation view of a single-keel boat with foldable forward planes and propulsion drives according to some embodiments, where a boat 201 provided with a hydrodynamic system following this invention and comprising two forward vortex-generating cambered planing surfaces 203 separated from the bottom of the boat 201 and one center-plane-located aft cambered planing surface 208 integrated into the aft part of boat's bottom, so that the planing surfaces 203 and 208 arranged spatially and angularly, and the surface 208 configured in the way ensuring generation and use of the effect of the ascending flow in accordance with this invention, which embodiment results in low drag and high hydrodynamic efficiency of the boat 201.

[0356] The boat 201 provided with semi-submerged counter-rotating propulsion propellers 1301 with their directions of rotation 1302 supported by propulsion drives 1501 arranged similarly the configuration of the FIG. 15 along the length of the boat downstream the forward planing surfaces 203 and upstream the aft planing surface 208, so that the axes of rotation of propellers 1301 are basically coaxial with the axes of the cords of vortices shed from the forward planing surfaces 203.

[0357] As a result of this embodiment, in high-speed operational mode, rotation of propellers 1301 corresponding directions 1302 leads to an additional upward component of the flow velocity vector in the gap between the forward planing surfaces 203, which upward component will increase the angle of slope of the ascending flow further downstream, resulting in the sections of the aft planing surface 208, to be conformal to the ascending flow, shifted vertically against the base lines of the forward planing surfaces 203 and arrange at a larger negative (nose-dive) angle, and thereby reduce drag and increase the hydrodynamic efficiency of the boat 201.

[0358] In this embodiment each of the forward planing surfaces 203 is made foldable and connected structurally with the bottom not by fixed struts, but by means of double-rocker mechanism comprising rocking struts 1601 and hinges 1602 with longitudinal axes, which makes the forward planing surfaces 203 able to snuggle against the hull of the boat, while propulsion drives 1501 with propellers 1301 made capable of pivoting laterally upward around the longitudinal axes.

[0359] In this FIG. 16 both forward planing surfaces 203 and propulsion drives 1501 with propellers 1301 are shown in unfolded position corresponding principal high-speed operational mode of the boat 201.

[0360] Through separating the forward planing surfaces 203 from the bottom of the boat 201 the bottom surfaces of the boat at its bow part made with high angle of deadrise indicated by the dotted line 402 (much higher than the hydrodynamically optimum angle of deadrise of the plane 203), which ensure sharp entry considerably upgrading seaworthiness of the boat, but not sacrificing lift and hydrodynamic efficiency (provided by the hydrodynamically efficient design of this invention).

[0361] FIG. 17 depicts a schematic diagram illustrating the front elevation view of a single-keel boat according to some embodiments and basically corresponding to the embodiment of the FIG. 16, but with foldable forward planes and propulsion drives shown in the retracted position, where the boat 201 with its bow part made with large angle of deadrise indicated by the dotted line 402, provided with two forward cambered planing surfaces 203 separated from the bottom of the boat 201 and one center-plane-located aft cambered planing surface 208 integrated into the aft part of boat's bottom.

[0362] Like in the embodiment of the FIG. 16, in this embodiment each of the forward planing surfaces 203 made foldable and connected structurally with the bottom not by fixed struts, but by means of double-rocker mechanism comprising rocking struts 1601 and hinges 1602 with longitudinal axes, while in this figure the forward planing surfaces 203 shown snuggled against the hull of the boat and the propulsion drives 1501 with propellers 1301 pivoted laterally upward around the longitudinal axes, so that both the forward planing surfaces 203 and the propulsion drives 1501 with propellers 1301 do not protrude below the keel line and beyond the dimensions of the boat 201 as a whole, ensuring shallow draft in the displacement mode and trailerability.

[0363] As a variant of the shown embodiment, both the forward planing surfaces 203 and the drives 1501 with propellers 1301 in the folded position can be retracted into special recess niches on the bottom of the boat 201 to make them flush with the bottom surfaces.