EFFICIENCY IMPROVEMENTS FOR FLOW CONTROL BODY AND SYSTEM SHOCKS

Abstract

Methods and related apparatus embodiments are disclosed that allow novel Conformal Vortex Generator and/or Elastomeric Vortex Generator art to improve energy efficiency and control capabilities at many surface points of a body or object moving at speed in aero/hydrodynamic Newtonian fluids, by reducing; shock energy losses, surface flow turbulence, and/or momentum layer thicknesses.

Claims

1. A method applied to an aero/hydrodynamic surface employed to modify a Newtonian fluid-flow, so as to mitigate a shock loss and/or lower the viscous drag on a downstream surface, comprising: (i) said aero/hydrodynamic surface employed to modify a Newtonian fluid-flow with the addition of, (ii) at least one conformal vortex generator means that is configured with flow-angled aft facing steps to generate sub-boundary layer streaming vortices from rear pointing tip locations in the local freestream direction onto said downstream surface, and that is configured for shock interaction effectiveness, whereby application of said conformal vortex generator means reduces shock loss and/or improves viscous drag on a downstream surface.

2. The method defined in claim 1 wherein said conformal vortex generator means is integrated into the design of said aero/hydrodynamic surface allowing improved operating capability.

3. The method defined in claim 2 wherein said conformal vortex generator means is integral to and configured during the design and/or testing process of said aero/hydrodynamic surface to reduce shock loss.

4. The method defined in claim 1 wherein said conformal vortex generator means is configured upon said existing aero/hydrodynamic surface to reduce shock loss and viscous drag.

5. The method defined in claim 4 wherein said integrated conformal vortex generator is configured during a testing process of operating said aero/hydrodynamic surface to reduce shock losses and viscous drag.

6. The methods of claim 3 and claim 5 where said aero/hydrodynamic surface is a foil operating in a gaseous Newtonian fluid-flow.

7. The method of claim 6 where said foil is a is a member of the group comprising; a wing means, a bypass-fan means, a compressor blade means, a rotor foil means, a stator foil means, a propeller blade means, a fluid-flow ducting means, a combustor surface means or a turbine blade means, and employs at least one said conformal vortex generator means on said aero/hydrodynamic surface to reduce shock losses and viscous drag.

8. The method of claim 7 wherein said wing means is configured with a leading edge Slat lift-enhancing means.

9. The method of claim 8 wherein said conformal vortex generator means is configured on a suction surface behind said leading edge Slat lift enhancing means.

10. The method of claim 9 wherein said conformal vortex generator means configured on a suction surface behind said leading edge Slat lift enhancing means is attached such that it is replaceable for maintenance and is protected from leading edge damage and/or detachment by a buffer alignment strip means.

11. The method of claim 10 wherein said buffer alignment strip means provides a permanent method to align said conformal vortex generator during a maintenance process.

12. The method of claim 1 wherein said conformal vortex generator means is configured to generate vortex filaments that act to modify acoustic wave propagation to suppress generated noise.

13. The method of claim 1 wherein said conformal vortex generator means is modified with a leading edge induction groove to improve flow attachment in deep dynamic stall conditions and/or lower the foil pitching moment.

14. The method of claim 1 wherein said conformal vortex generator means is applied on a wing means modified with the combination of a trailing edge elastomeric lift enhancing tab means to further move a shock rearwards on the foil surface and enhance shock loss improvements.

15. The method of claim 9 wherein said conformal vortex generator means configured on a suction surface behind said leading edge Slat lift enhancing means is followed by a second instance of conformal vortex generator means closer to a shock to improve boundary layer energy and shock mitigation.

16. The method of claim 9 wherein said conformal vortex generator means configured on a suction surface behind said leading edge Slat lift enhancing means is extended underneath said leading edge Slat lift enhancing means to a pressure face location.

17. The method of claim 16 wherein extended said conformal vortex generator means is configured with a low surface-energy material surface presented to said leading edge Slat lift enhancing means to provide a friction lowering and/or abrasion resistance capability.

18. The method of claim 14 wherein trailing edge elastomeric lift enhancing tab means has the addition of a buffer alignment strip means to provide a permanent method to align said conformal vortex generator during a maintenance process.

19. The method of claim 14 wherein trailing edge elastomeric lift enhancing tab means has the addition of buffer alignment strip means to protect an adhesion interface.

20. The method of claim 8 wherein said a leading edge Slat lift-enhancing means is modified by addition of elastomeric vortex generators in the slat gap to create a gap seal when retracted and thus lower cruise condition losses.

21. The method of claim 8 wherein said a leading edge Slat lift-enhancing means is modified by addition of elastomeric vortex generators in the slat gap to create vortices that enhance lift when the slat is extended.

22. The method of claim 8 wherein said leading edge Slat lift-enhancing means is modified by addition of a flexible trailing edge extension with a configured conformal vortex generator means that further acts as a compliant bridge across a trailing edge gap to a following wing surface to minimize losses when said leading edge Slat lift-enhancing means is retracted.

23. The method of claim 7 wherein said wing means employing said conformal vortex generator is configured by removal of existing blade vortex generators to lower drag, whilst maintaining required vortex action for shock interaction.

24. The method of claim 7 wherein said propeller blade means, employing said conformal vortex generator, is configured without requiring blade sweep to mitigate shock losses.

25. The method of claim 7 wherein said wing means employing said conformal vortex generator is configured to increase a critical mach number to allow higher speed operation.

26. The method of claim 3 wherein said conformal vortex generator is configured on a cylindrical Sears-Haack body or equivalent configuration body to lower shock losses.

27. The method of claim 26 wherein said cylindrical Sears-Haack body or equivalent configuration body is an aircraft fuselage.

28. A Newtonian fluid-flow aero/hydrodynamic processing apparatus employed to modify a Newtonian fluid-flow, so as to mitigate a shock loss and/or lower the viscous drag on a downstream surface, comprising: (i) said aero/hydrodynamic surface employed to modify a Newtonian fluid-flow with the addition of, (ii) at least one conformal vortex generator that is configured with flow-angled aft facing steps to generate sub-boundary layer streaming vortices from rear pointing tip locations in the local freestream direction onto said downstream surface, and that is configured for shock interaction effectiveness, whereby application of said conformal vortex generator reduces shock loss and/or improves viscous drag on a downstream surface.

29. The apparatus defined in claim 28 wherein said conformal vortex generator is an integrated conformal vortex generator that is integrally embedded in said aero/hydrodynamic surface.

30. The apparatus defined in claim 28 wherein said conformal vortex generator is configured to generate vortex filaments that act to modify acoustic wave propagation to suppress generated noise.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS: (5 SHEETS)

[0096] All drawings are not to scale, but are detailed with many optional embodiment features, for illustrative purposes.

[0097] FIG. 1 details a wing underside view representation employing a TE flap and LE Slat (extended) arrangement to improve low speed lift capability, along with CVG and eLET arrays to improve performance.

[0098] FIG. 2 details a cross section of the TE embodiment of an eLET tab and buffer alignment strip art that provides improvements in wing efficiency and operating range, particularly in combination with CVG's improving shock losses.

[0099] FIG. 3 details an embodiment of an elastomeric vortex generator (eVG) art that provides a wing high speed cruising mode Slat-retracted gap-seal capability and/or improved Slat-extended wing stall capability at low speeds, as well as cross sectional variations of eLET and eVG body shapes.

[0100] FIG. 4 details a wing topside representation employing a TE flap and LE Slat (extended) arrangement to improve low speed lift capability, along with CVG arrays to improve performance by reducing shock and flow losses.

[0101] FIG. 5 details a wing cross section representation with a LE Slat (retracted) arrangement that outlines the relative effects of prior art blade VG and new art CVGs in modifying wave drag by lambda shock-foot impingement.

[0102] FIG. 6 details an alternative CVG embodiment at a slat trailing edge.

[0103] FIG. 7 details a turbine blade cascade showing locations of typical shock and other losses.

[0104] FIG. 8 details a compressor blade cascade showing locations of typical passage shocks.

[0105] FIG. 9 details a foil LE with an embodiment that suppresses deep dynamic stall Cm.

[0106] FIG. 10 shows a cross-section of a high speed vehicle with scramj et propulsion that benefits from multiple applications of integrated CVG's to suppress shocks and flow problems.

DETAILED DESCRIPTION AND BEST MODE FOR CARRYING OUT INVENTION EMBODIMENTS

[0107] FIG. 1 shows the arrangement of a common example of a wing 2 with both a downward deflecting TE flap 3 before the TE 15, and a LE Slat 4 in the un-retracted low-speed position at the wing LE 16. The relative incoming fluid-flow or upstream freestream 1 is shown by an arrow and this allows the AoA to be defined by the relative angular deflection of the wing chord line (or the flow control surface extents) from this freestream velocity vector. Slat slot 5 open in the low-speed extended configuration accelerates additional fluid-flow over the wing top or suction face 6. A wing pressure face 7 TE array of eLET body 8 are configured as the required coverage from near the wing tip 12 to wing root, and possible Yehudi root rear chord extension 9. Wing TE array of eLET body 8 are applied in sections to ensure fault-tolerance if any section becomes detached in flight. This is critically important because this TE array of eLET body 8 addition changes the local wing C.sub.L, as well as C.sub.D, which has the effect of creating a possible wing roll-moment input if reasonable wing lift-symmetry is not maintained. The eLET section gaps 11 may be configured as; closed to any fluid-flow or wide enough and angled so as to add selectable and controlled streamwise wake TE vorticity from these structures, that are situated wholly before the wing TE and the trailing Kutta-Zhukovsky exit condition at 29. The TE array of eLET body 8 is shown optionally attached onto the flap 3 and TE fixed and control surfaces. This is possible because this new-art configuration is a low-mass compliant and active aerodynamic structure with shear force spreading capability that puts minimal stress on the thin TE of these flutter-sensitive control surfaces.

[0108] FIG. 2 shows the addition of an eLET body 8 with tab offset 20 from the TE 15 of the rear portion of a wing foil, which allows the generation of typically two or more compact spanwise vortices, e.g. rear tab vortex 23 and forward tab vortex 24. These two tab vortices act to add extra force on the fluid-flow exiting the TE 15 and acts to increase the downwash vector angle towards the pressure-face side and hence increase lift vector, in the opposite direction. This also communicates extra flow velocity upstream along the suction face streamline 28 into the sub-sonic part of the suction BL after any normal shock (where Mach number transitions to less than 1.0) and effectively makes the foil chord appear to be aerodynamically extended, and lowers drag. Ahead of the eLET body 8 may be configured an entry transverse entry-vortex 25 that conditions the entry pressure face streamline 27 for lowest energy configuration. Fluid flows are indicated with small arrows on the dashed fluid-flow lines. The eLET body 8 is typically adhered by eLET adhesive 21 to and/or behind a buffer alignment strip 22 that then is permanently affixed accurately to the pressure face 7 at the design location. The strength, flexibility and/or persistence/life of eLET adhesive 21 is chosen to be suitable to allow for easy eLET removability and maintainability, whilst being sufficiently strong to attach eLET body 8 reliably over its designed operating life, and be resistant to any chemicals like; cleaners, anti-ice compounds, fuels, lubricants and hydraulic fluids etc., that may be present. Buffer alignment strip 22 is configured to provide a durable and permanently attached base to support eLET body 8 and has a forward profile that is configured in any functional way to fundamentally overlap and cover or shield the leading edge of eLET adhesive 21 from impact damage from service handling and impacting matter/debris such as; ice crystals, rain/liquids, dust, sand, volcanic ash and insects etc. These may impact at high velocity closely along the incoming BL and hence could disrupt the adhesion of a lower-strength but easily serviceable bonding system like item 21. Buffer alignment strip 22 may be omitted, and eLET body 8 bonded directly with a high-strength and/or permanent adhesive system, but that then is an inferior embodiment, because it is harder to maintain and service time-efficiently when an in-use condition requires repairs. A permanent adhesive type system will typically leave a surface residue or damage when mechanically or chemically removed, which makes the maintenance process more complex, time intensive and costly, since damage to the surface or protective paint cover then needs to be corrected.

[0109] Buffer alignment strip 22 may be fabricated in any material of suitable density and flexibility that is durable for incoming matter impacts, with surface energy configured for attachment; which could be a mechanical fastener or adhesive system against the pressure face 7. It can be formed by any known or future art manufacturing process, to dimensions that are suitable to shield the size of the; chosen eLET adhesive 21, and the eLET body 8 size being used on the particular foil, which is a typical height of 0.1% to 3% of foil chord, depending on desired aerodynamic effects. Tab offset 20 is typically in a range of zero to approximately 5 tab heights forward of the TE, but this is not a limiting condition, and can be adjusted as required to modify the tab-induced shift in either; drag, lift and/or L/D ratio. Setback from the TE of the eLET body 8 by Tab offset 20 as a fraction to several tab heights, allows for improved downwash magnitudes and higher effectiveness, depending on whether a lower-drag or higher-lift configuration optimization is desired. Tab width will vary depending on configuration and typically a tab height-to-width ratio of 0.1 to 5 is practical. Final testing on a flight surface determines the best embodiment final dimensions, based on the general configurations taught herein.

[0110] FIG. 2 also shows an alternate buffer alignment strip 31 version that may be adhered wholly underneath the extent of eLET body 8 and on pressure face 7, and extend back to the TE 15. This makes installation easy to perform and verify but slightly heavier and less flexible. It is possible to reduce the buffer alignment aft section so as terminate under the eLET body 8 at the rear, as a medium length buffer alignment strip 30 or even terminate at the eLET body 8 front-face as a shortest buffer alignment strip 22 (not adhering under the eLET body 8), as shown for approximate size comparison. Buffer alignment strip 30 is shown with a square LE entry which is to indicate that this entry geometry is not critical and that this buffer strip is present to protect the eLET adhesive 21 interface. Note that the diagrams are not strictly to scale; and for example the adhesive 21 thickness is exaggerated for illustrative purposes. In a functional embodiment of this new art, the most critical dimensions are the tab heights of eLET body 8 and Tab offset 20, as discussed, and variations of these embodiments and geometry are possible and considered as part of this new art.

[0111] eLET body 8 can be a solid block of suitable material as shown, or configured as one of numerous variants such as; a U form item 33, an F form item 32, T item 34, L item 35, Pi item 36 configuration etc., and formed in an Open-cell or preferably Closed-cell interior low-density foam or elastomeric material so as not to retain any liquids, contaminants or dust etc. Variations in the part geometry and e.g. edge radii based on these fundamental shapes are possible and considered within the scope of this new art. eLET body 8 and/or variations are typically fabricated and processed in one or more steps, with one or more materials to form essentially a smooth-skinned or effective attachment surface at the attachment area or point. A mix of foam densities and elastomeric/plastic materials can be combined and then configured for best performance. In the U form item 33 configuration shown as a variation overlaid in FIG. 2 as a dashed line modification, a tab internal vortex 26 is induced that helps keep the thin eLET walls from collapsing from the greatest aerodynamic forces acting along the streamline direction. The viscous energy cost for any supporting vortex structure is balanced against the value of having a smaller volume or lower mass tab configuration.

[0112] Unexpectedly, the low mass and high flexibility and compressibility of an elastomeric material, in essentially a unique aero/hydrodynamic force balance, is very effective at holding its required shape and inducing desired beneficial vorticities, even up to transonic or local supersonic flow velocities. This compliant elastomeric material system also filters aero/hydrodynamic forces, pressures and acoustic noise and stresses from coupling to the underlying surfaces, and places the absolute minimum of added; weight, inertia, fatigue and stress onto the underlying surface.

[0113] Of particular note is that the elastomeric body material(s) and adhesive attachment system form a unique system that unexpectedly can attach dissimilar materials onto an aero/hydrodynamic flow-control surface (like a; wing foil, hydrofoil, support strut, rotor blade or propeller, etc.) in a highly stressed situation and provide retention in the face of large aero/hydrodynamic forces, and particularly very high inertial accelerations if rotating.

[0114] Retention of elastomeric materials as e.g. tabs, VG and CVG structures on jet engine fan blades at 61,000 gravities or more are unexpectedly much greater than the bonding capabilities suggested by e.g. common ASTM materials specifications and test methodologies of the baseline adhesives and materials. This unexpected outcome is due to the fact that an elastomeric material is capable of inherently flexing and distributing and thus equalizing all the aero/hydrodynamic, inertial or other forces evenly across the complete bonding interface area, such that any local surface interface slip-condition that could rupture attachment is not exceeded on both the; (a) substrate to adhesive interface and (b) the adhesive to elastomeric body interface. This force-balancing and load-strain sharing is due to the unique combined employment of; flexible adhesive systems coupled with a flexible elastomeric elements being attached. This is clearly not the case for prior art e.g. a metal tab or VG structure, and/or systems employing a semi-rigid adhesive system like an epoxy resin or similar. A metal tab is essentially crystalline and rigid at its surface and so cannot readily redistribute local bonding forces from across the adhesive interface, which means that once any local adhesive area exceeds the local adhesive force resisting capability, then a local surface rupture and hence bond failure will occur. These adhesive and joint stresses may be induced by; inertial, shock impact, varying aero/hydrodynamic forces, differences in material temperature and thermal expansion coefficients, material contamination, water freezing in associated small cracks, etc. In this inflexible joint condition, the local bond failure is not self-correcting so as to equalize local strain, and so a joint failure will progress from the location of lowest strength and/or maximum strain until the complete attachment surface fails. Flexible and/or plastic non-rigid materials are preferred for eLET body 8 along with adhesives that retain flexibility and joint force distribution. Buffer alignment strip 22 is a smaller structure, so may be less flexible material and applied in adjoining sections, so as to not induce high strains on the underlying surfaces with flexure and vibration.

[0115] There are a large range of flexible adhesives like; acrylics, polysulfides/polysufones, silicones, polyurethanes, vinyls, EPDM and natural rubbers etc., that can be paired with these new art aero/hydrodynamic elastomeric structures to yield the novel capabilities taught herein. A further refinement of elastomeric tabs, VG and CVG structures is to apply an e.g.; cast, sprayed or mold-formed or squeegeed/extruded or similar application of; flexible resin systems or material onto a substrate, and hence employ the material's internal homogenous self-bonding capability to also form the desired adhesive interface onto this clean and prepared flow control surface. In this combined eLET body 8 and adhesive 21 single part embodiment, the material is flexible and is configured as required after processing on the surface, to form the final new art aero/hydrodynamic shape or structure. This can be as effective as a combined elastomeric/adhesive system, but with lower ease of maintenance since removal and rework is more complex.

[0116] FIG. 3 is a wing top view looking forward into a slat slot 5 and shows an embodiment using a combination of elastomeric VG's (eVG's) optionally configured across this wing Slat slot so as to seal off any unwanted or disruptive slot leakage when the Slat is retracted in the cruise condition. In this case the unique capability of a formed elastomeric VG is to compress and become a seal in a retracted or closed Slat gap for improved cruise conditions and then expand back into a different functional form when the Slat is extended at low speeds. This embodiment contrasts with the turbulence and loss-causing prior art transverse Slat seal 106 and may be employed separately or in combination. An elastomeric VG shape is chosen because in the Slat-extended lower-speed case the high-energy slot airflow should suffer minimum flow blockage, and an eVG shape in the gap adds extra controlled beneficial vorticity to the energizing pressure-face fluid-flow; and so improves suction face flow attachment and allows a higher stall-AoA capability. Elastomeric VGs; as wing eVG 40 or slat eVG 41 can be formed with e.g.; square, T, L, F or U shapes and materials and attachment as variant of eLET body 8 art, and can both be angled to the freestream flow at about a 22 degree angle, or angled as required in the local flow conditions, so as to induce most efficient vortex generation. The size, locations and profiles of these eVG's are configured so that an effective flow seal TE eVG overlap 42 and LE eVG overlap 43 are formed by slight edge to edge eVG contact interference when the Slat is retracted and the slot gap is at a minimum. Depending on Slat gap geometry, the shed streamwise eVG 40 and 41 vortex filaments may be in close proximity and interact. An alternate embodiment avoiding this uses straight eVG 50 items on the slat attached along the freestream direction so they do not create significant vorticity, but still cooperate with the other angled eVG 40 vorticity generating set in an alternating array to seal the gap when in the cruise condition. Of course any of the buffer alignment strip methods may be added to these eVG embodiments. In the case of a SSTO type vehicle added eVG vorticity in a Slat gap analog allows a greater turning angle in the transition to suction face flows and slower approach and/or takeoff speeds for the delta wing or lifting body. The eLET body 8 may be formed from extrusions, or molded, bonded and machined to final sizes and shapes.

[0117] In transonic flight, highest cruise speeds are limited by sharply increasing Mach-shocks and wave-drag that effectively defines a wing-drag predominated Mcrit limitation. This non-linear drag increase is mostly driven by the wing suction face 6 (and to a lesser degree pressure face 7) normal-shocks which force an upset or detachment of the BL at the SBLI and representative Lambda-foot shock position. This dramatically increases shock and entropy/energy losses on the typically largest linear-dimension aerodynamic structure across the freestream flow. Clearly other control surface and structures like the fuselage, empennage etc., also enter flow shocks at other airspeeds defined by their flow geometry, and can also have losses usefully mitigated by this new art, but this wing embodiment is the focus of new art CVG application to mitigate wing shock losses as shown in FIG. 4.

[0118] Wrap CVG array 14 is shown that extends from the wing suction face 6 through the Slat slot 5 and onto the pressure face 7. This wrap CVG array 14 configuration (and/or other CVG) is optimized to generate intense and very persistent counter-rotating sub-BL streaming tip vortex-pairs from the incoming suction face freestream flows behind the Slat upper TE. These tip vorticies then impinge on the following suction face Lambda-foot shock 18 along shock line 17 and hence lower shock losses and/or wave drag at e.g. cruise conditions, when the Slat is retracted and the slot closed. The bend in shock line 17 points out that the wing section with Slat coverage disturbances tends to let the shock come forward due to the added BL stresses. The addition of CVG's drives the shock line 17 rearwards and the combination with eLET body 8 configured at the TE further improves shock mitigation and performance improvements. Top of shock 19 is indicated, and this is the limiting height from the flow surface and behind the LE that the displaced external freestream flow can experience acceleration to Mach1.0 due to the foil passage. Wrap CVG array 14 is placed further back from a typical CVG location on the Slat forward face (that would be optimized for a higher velocity freestream flow), and this is because an additional goal beyond shock loss mitigation is this CVG array is also employed to re-laminarize the Slat TE AFS disturbance and BL flow transition to turbulence. This is configured to thin the Slat downstream BL or momentum thickness, reduce Turbulent Kinetic Energy (TKE) generation and mitigate the excess drag caused by this Slat TE disturbance. On the pressure face, wrap CVG array 14 acts after the lower Slat TE flow disturbance in the same manner, and also mitigates the pressure face Lambda-foot shocks along shock line 10. For clarity only one or two sections of CVG's are shown in these figures, but it is to be understood that the embodiment is generally across a majority of the surface span(s) employing a number of CVG sections or elements as needed. These CVG elements essentially show an entry forward facing step that is angled to the freestream and these do not shed vorticity in the same way as an AFS.

[0119] On a wing with physically large or cumbersome Slat gap sizing, it is most convenient to assemble sections of a functional wrap CVG array 14 by using a number of shorter chordwise sections that are abutted in the spanwise direction with joints that allow a best outer surface continuity and surface BL flow. This effectively provides a wing LE wrap with the CVG pattern at the rearmost section TE's. In the spanwise direction, these groups of sections forming a wrap CVG array 14 are affixed adjacently and can be locally adjusted for mechanical clearances and attachments and local flow conditions, since along the span the chord changes dimension and the CVG's can be optimized for this. The spanwise Slat TE extent 101 dotted line on FIG. 4 wrap CVG array 14 shows where the slat TE comes to rest. CVG sections may be configured to be applied in different size groups but this is not limiting and the demarcation can be at multiple places and in any convenient geometry to allow alignment with items like interlocking joggles or features like a jigsaw puzzle teeth to help in alignment.

[0120] Since the Slat gap is often quite narrow, long, and the middle and lower sections may be crowded with actuation, control devices and access panels, in some embodiments it may not be practical to install and/or service some sections of wrap CVG array 14 through the Slat slot, as would be ideal. An alternate CVG embodiment is to employ a partial suction face CVG array 44 along with a partial pressure face CVG array 46 (also see FIG. 5). These partial CVG arrays 44 and 46 may be attached with a linear front entry edge that is at approximately right angles (transverse) to the freestream flow and will then generate a small low-loss LE transverse step-up vortex at this front step, similar to entry-vortex 25. As for the eLET attachment reliability, a suction CVG buffer alignment strip 45 and pressure CVG buffer alignment strip 47 can be added for mechanical integrity and adhesion protection. Partial suction face CVG array 44 may be partly shielded from the cruise velocity freestream fluid-flow by the Slat TE step and in fact can be configured with a setback from the Slat to generate a vortex channel 59 with a trapped spanwise channel vortex. Because of mechanical tolerances and movements it is not practical to abut CVG's directly and consistently exactly against the Slat TE with no entry flow disturbance, so in almost all cases there will be some form of transitional transverse gap or channel.

[0121] An additional CVG embodiment is to employ a partial suction face shock CVG array 102 along with a partial pressure face shock CVG array 103 with alignment buffer strips 107 and 105 respectively. These partial CVG's are located closer to the cruise shock foot and with the upstream CVG's improving the aft BL energy, there is additional BK organization possible to help improve losses. After the TE control surface start edges (e.g. flaps or spoilers) it is also possible to have control partial CVG array like 104.

[0122] A spanwise or transverse channel vortex or step-up vortex tends to have a circulation field that provides a slight down-force at the CVG entry surface-normal edge, and this does not tend to lift this entry edge, unless this has been disturbed mechanically and uplifted. CVG buffer alignment strip 45 and 47 (and others) are provided to protect and guard against this possibility of element LE detachment and are configured as for the eLET and eVG usage, being modified to account for thinner CVG geometry, and additionally provide a useful alignment edge when changing elastomeric elements. Since CVG's are applied in a series of abutting and convenient sized elements or sections, if a single section detaches unexpectedly, it is not catastrophic and the material loss is limited to the separated section. In front of e.g. an engine air intake, the attachment of the CVG would have to be a less convenient and more permanent type of material (such as metal) and/or adhesive. The application of CVG's in short sections also ensures that if a less flexible material such as metal, or a harder and less malleable material is used to fabricate the CVG, the underlying surface accrues a minimum of extra strain when flexing against these separated CVG sections, that have slight chordwise application tolerance and expansion gaps included between them to allow expansion and flexing of the underlying substrate or surface.

[0123] Set-forward partial CVG array 48 is an alternative embodiment, where a partial CVG array has its forward edge placed into the Slat slot 5 under and forward of the retracted Slat TE marked by the Slat TE extent 101 dotted line. This provides a non-channel form and minimum step change arrangement in the cruise configuration. This set-forward partial CVG array 48 element and combination of similar abutting elements is sized to correctly stream tip-vorticity into a following SBLI, and also may employ a forward buffer alignment strip arrangement to protect against material impacts through the extended Slat slot 5. Set-forward partial CVG array 48 element(s) and/or an associated matching alignment strip geometry may also be fabricated with, or incorporate an additional top layer of, low surface-energy material like e.g. PTFE around the area of Slat contact that can then act as a sacrificial rub, chafe prevention or anti-friction surface. This ensures that Slat contact on the prior wing surface paint does not cause damage, which otherwise allows surface corrosion to occur on the wing. The wing paint in this area may be then changed from the anti-friction type to higher energy paint that allows for better CVG adhesion. An anti-friction version of Set-forward partial CVG array 48 shown has an additional dotted line to indicate the variation of some forward portion as an anti-chafe feature and/or buffer alignment strip feature, and this leading edge has been provided with optional flow-angled sections that allow the incoming edge step vortices to flow to the side to discharge these vortex fluid flows in a manner that does not perturb the following CVG v-form step sections.

[0124] Any of these CVG elements may be fabricated in a transparent material that may have; manufacturing, batch, or part numbers, or any other fixed or variable display information reverse printed on the lower adhesive/attachment face. This may be installed, or additionally laminated onto a lower layer top-surface with any of the same types of display information; all of which will then be visible externally and protected from damage in operation.

[0125] Internal acoustic partial CVG array 58 may be placed before the inside TE of Slat 4 and is added to generate vorticity at the TE to improve flow mixing between Slat slot 5 flow and the freestream only when the slat is deployed, to reduce the acoustic signature due to this noisy slot fluid-flow region. Forward Slat LE CVG array 49 may also optionally and additionally be applied to the Slat outside LE to provide extra high-velocity BL energization, particularly at high AoA, approaching wing-stall with extended slats, and can be followed by any other CVG embodiments.

[0126] Curved fuselage panel 108 is shown adjacent to the wing root, but in fact it can be any surface or part of a cylindrical surface like a Sears-Haack body, exposed to the upstream freestream 1 that can be improved for shock and/or separation losses at high speed. Non-planar CVG array 109 is attached as shown at the correct orientation to the freestream with the v-tips producing intense downstream vortices to improve BL subject to shocks and disturbances such as flow interferences between these joined wing and fuselage bodies. The LE step of non-planar CVG array 109 is shown with a sweep angle to the freestream (like the wing CVGs) and this ensures the forward facing step vortex can discharge the step vortex filament and so be controlled in accumulation size to minimize entry losses. This example of non-planar CVG array 109 may be repeated as combinations of elements in series along and around the fuselage, or other bodies and can improve shock and separations around surface discontinuities like cockpit windows and doors etc. One of the greatest points of shock generation at high speed in a Newtonian fluid-flow on a Sears-Haack or similar cylindrical body like a; fuselage, tank, pod, projectile etc., is at the generally conical nose to cylindrical body transition blend or brow, where the bow shock, compressibility and flow transitions can help induce trailing normal and/or oblique shocks and turbulent separation as the flow accelerates around the body blending. Upstream instances of non-planar CVG array 109 may be attached to stream dense concentrations of tip vorticity to mitigate the lambda shock foot and lessens the flow losses and turbulence and acoustic noise generation. In a liquid medium the velocities are lower and compressibility shocks are replaced by flow separation, cavitation and turbulence.

[0127] Note that all combinations of CVG embodiment materials, sizes and configurations that perform the function(s) of; drag reduction, stall AoA extension, and flow separation improvements are considered as disclosed by this new art, and combinations of different embodiment types and numbers of these types of arrays may be chosen for any particular application. For a typical e.g. wing or flow control surface, a CVG step height of 0.25 mm to 5 mm (depending on flow speed and location) and a step length of 5 mm to 30 mm may be employed, and the optimized values then depend on testing at the design flow parameters such as; cruise Mach number, chord length, relative shock location distance and shock mitigation target chosen. For higher speed operation optimizing shock mitigation, a higher density of vortices (i.e. shorter step lengths) placed closer to the lambda-foot is chosen, and coverage of CVG sizes may be modified locally to be optimal at any application location. The nominal best CVG vorticity angle is typically about 22 degrees to local freestream flow and this can be modified locally to account for cross-flows, local flow changes etc., with the goal of creating greatest operating vorticity at lowest energy cost. Note that these typical parameters suggested are not limiting and the final determinant of any CVG embodiment is the correct generation of the novel beneficial effects to; mitigate shocks, reduce turbulence losses and reduce flow separations. The effect of CVG's also include the ability to desensitize the following BL to upstream flow perturbations like damage, dirt and other discontinuities.

[0128] Turbulator strip 100 is shown on the wing 2 suction face 6, and this prior art does not provide the performance improvements achieved by a CVG array. This is generally due to the fact that Turbulators are not optimized for streaming vorticity, but nominally BL turbulence generation, which the prior art practitioners consistently consider the prerequisite for improving BL attachment and loss control. Even though turbulators may be quite thin, the entry forward-facing steps and tips generate manifold entry fluid-flow patterns that interfere with their trailing edge aerodynamic flow effects (particularly with varying flow yaw), so it is almost impossible to reliably generate intense streaming vorticity to interact with a downstream SBLI or thin the downstream momentum layer thickness, and so reduce drag.

[0129] FIG. 5 shows a cross section of an improved configuration as an embodiment employing wing eVG array 40 or slat eVG array 41 in the overlap region with the Slat 4. These eVG devices are configured conforming to the wing/slat surface, are angled to the slot gap airflow to generate contra-rotating streaming vortices in the gap in the freestream direction, and have minimal or zero LE eVG overlap 43 or TE eVG overlap 42 between them at their upstream LE and downstream TE points respectively. These eVG array 40 devices are configured with sufficient exit height to generate strong vortices along the wing LE suction face curvature that additionally improves the wing flow separation resistance and increases wing stall AoA.

[0130] On the inside surface of Slat 4 the slat eVG 41 instances will generate a second set of co-rotating free-stream vortices in the opposite direction into the freestream flow on the opposite side of the slot gap and exit at the Slat TE. This Slat inner surface vorticity is not as beneficial to directly improve wing 2 flow-attachment or stall AoA capability. In the retracted case the Slat retracts closer to the wing and since the eVG array 40/41 devices are elastomeric they can be partly compressed in the remaining slot gap to provide a measure of sealing of slot gap air leakage in the cruise condition. When the Slat 4 is retracted the location of the two arrays wing eVG array 40 and slat eVG array 41 instances are configured to slightly overlap so a complete spanwise Slat seal is created. A slight interference or overlap wing eVG array 40 or slat eVG array 41 instance tips is possible and the elastomeric geometry and material can be e.g. tapered and configured geometrically at the ends to provide a consistent seal and effective VG operation in two of the distinct Slat operating states. This allows a fluid-flow improvement in different usage conditions or positions of the Slats.

[0131] Conventional or e.g. metal VG's cannot be placed into the slot gap because the clearances are not exact and/or predictable, and an over-height non-compliant VG will place undue stress on the retracting Slat and prevent proper stowage to the final stop points. Elastomeric Vortex Generator's 40/41 are configured by materials design, geometry and manufacturing to reliably compress with minimal force and restore fully to VG function in the Slat extended case. Accelerated airflows through the open Slat slot 5 can be high at takeoff and landing and transitions and it is an unexpected outcome that a typically lightweight elastomeric material can remain attached and minimally deflected in these flows of many hundreds of feet per second. This is due to the fact that an elastomeric material tends to equalize shear stresses along the attachment interfaces (typically some form of adhesive) and the vortex structures tend to support the upstream and downstream faces of the eVG array 40/41. Buffer alignment strips may also be employed to protect these eVG front edges, but this is not as critical as for devices that are subject to the cruise freestream flows.

[0132] A further embodiment is to provide only co-rotating streaming vortices on the wing 2 (versus the contra-rotating outcome in FIG. 3) it is possible to change e.g. all the inboard-pointing slat eVG array 41 instances to be aligned in the freestream direction as eVG 50 instances to generate no significant vorticity and place these in the required overlapping and sealing position on the inside face of the Slat 4. The remaining outboard-pointing wing eVG array 40 instances that are angled to freestream flow on the wing 2 will then stream co-rotating vortices along the wing 2 when the Slat slot 5 is open. Since these eVG instances now produce a co-1400 rotating and consistent flow vorticity (design-selectable in either vorticity direction) with no close by cancelling opposite flow, these can be configured to have an effect on the wing lift or total vorticity sum in either sense when the Slat is extended.

[0133] For new Slat designs the slot geometry and clearances can be configured for optimum sizes of wing eVG array 40 and slat eVG array 41. For existing Slat designs wing eVG array 40 and slat eVG array 41 are configured to allow retro-fit, and in some cases the inner slot surface of the Slat 4 may require the addition of a carrier surface to ensure the eVG arrays are correctly located in three dimensions. The wing 2 LE surface is typically smoothly contoured to allow wing eVG array 40 arrays to be retro-fitted. If the nominal Slat slot is too close, it is typically feasible to adjust the Slat retracted stop position to allow sufficient clearance for the wing eVG array 40 and slat eVG array 41 arrays to work correctly.

[0134] A prior art blade VG 51 is shown as dotted line on FIG. 5 wing cross section, and this streams prior-art vorticity 52 into the suction face normal shock above the shock Lambda-foot 18, 1415 because this design cannot stream vorticity closer to the foil surface. Item 54 shows the curve of typical momentum loss or entropy generation versus foil position immediately downstream of the foil TE, and item 55 is the summed area proportional to wave drag effects that the prior art blade VG 51 can help to alleviate. The highest entropy loss is close to the foil centerline due to foil drag and momentum losses and drops off either side until the foil has no effect on the external freestream or energy losses. This curve is qualitatively representational of the known physics and not quantitative in FIG. 5.

[0135] New art CVG vorticity 53 from partial suction face CVG array 44 is known to remain closely attached to the foil surface and streams through the strongest part of the shock Lambda-foot 18; which unmodified generates stronger entropy losses as the shock approaches the surface 1425 and/or the shock is intensified. This is an indication of why a CVG array is much more effective in reducing wave drag losses, as the relatively larger magnitude of summed loss area 56 indicates. The pressure face partial CVG array 46 is also active along to the shock foot location 10 and provides the loss improvement summed area 57, and this pressure face shock loss mitigation is not taught as this effective on shock losses on flight tested prior art wing embodiments.

[0136] FIG. 6 shows an alternate embodiment of a forward Slat LE CVG array 49 where a flexible after portion as CVG TE extension 60 is attached and brought back over and behind the Slat TE 63, with no adhesive behind the Slat TE 63 position. This allows the closed Slat to have an optimally located, selectively compliant and effective CVG trailing edge resting freely on the trailing wing surface, and the problematic Slat TE AFS discontinuity is bridged by a flexible film or membrane that can conform to the following wing surface and automatically follow the lowest-energy freestream configuration across the Slat TE AFS. Even though the Slat slot 5 is sealed when closed by e.g. transverse Slat seal 106, additional vent 61 through CVG TE extension 60 may be included to ensure no buildup of dynamic pressure differences, to keep this flexible film from being raised above the following wing surface with a closed slot. Hold-down compliance 62 means may be included which is an adhered array (or molded in) or attached linear spring-like device or material to add a fixed value of downwards alignment and compliant deflection and damping. This also ensures that CVG TE extension 60 acts correctly and is in a preferred essentially intimate contact with the following wing surface, as it deploys flexibly behind Slat TE 63 to a closed Slat position, and helps suppress vibration in the CVG membrane when the slat is extended.

[0137] In the low speed Slat-extended condition the natural slat opening and rotation condition holds the flexible CVG TE extension 60 above this now extended Slat slot 5 with an entrained accelerated fluid flow, and at the upper fluid-flow boundary these flexible CVG's act as freestream-located very low-height and drag off-surface vortex generators. These are configured and work very differently to e.g. Vijgen'665 and Balzer '106, since CVG TE extension 60 is significantly thinner membrane means, does not require a hinge means with actuator and incorporates; flexibility, device motion and compliance in more than one operating state, different geometry, turbulence mitigation across a closed mechanical Slat TE discontinuity, and/or effective downstream SBLI mitigation capability. The improved low drag VG action of flexible CVG's (even offset from a following surface) are not configured to change C.sub.L, and allow for mixing of the two fluid-flows across any existing flow shear to reduce acoustic noise.

[0138] The new art CVG TE extension 60 geometry, material and fabrication ensures that this flexible CVG body and v-tips assume a balanced dynamic area force loading and so remain in damped minimal motion around a steady mean position and automatically track the lowest-energy freestream force-balanced configuration during the limited low-speed portion of flight with slats extended, unlike a Vijgen'665 rigid panel which is adjustably positioned by an external actuation means. The flexible CVG material and optional hold-down compliance 62 act to damp any flutter and the CVG materials are configurable as elastomeric or plastic combinations to be highly resistant to mechanical fatigue. Since FIG. 6 embodiment is for a non-rotating foil case, it is also possible to follow CVG TE extension 60 on the wing with following instances of partial suction face CVG array 44, wrap CVG array 14 or set-forward partial CVG array 48 that may extend further back for additional CVG surface activity, and also eVG array 40/41 devices that may be employed within the slot itself. CVG TE extension 60 may also be integrated into Slat LE CVG array 49 as a single application unit. The combination of low surface-energy CVG materials with low thermal resistance allows the anti-ice bleed-air or electrically heated slat to maintain an ice free state.

[0139] FIG. 7 shows turbine blade 150 and turbine blade 151 in a cascade with overlap set by disc solidity value, and the disc axis angled to the LE and TE alignment shown. The incoming turbine freestream flow 148 enters at the operating inlet flow angle and then exits as the turbine outlet freestream 159, after undergoing the blade turning angle and extracting work from the fluid-flow kinetic energy. Incoming upstream blade wake transient 149 enters at the inlet flow angle and meets the suction face of blade 150 at the impact point 155, and this disturbance is then effectively reflected back to impact the suction face of the second blade 151. At the impact point on blade 151 this reflected transient splits into an aft flowing positive jet influence; and forward flowing negative jet 156 influence that then acts to slow the incoming blade 151 BL and so induce turbulence and premature transition, which increase flow losses. The TE 154 influence as defining the geometric end of the blade passage overlap with turbine blade 151, induces a pressure transition and a TE shock 157 on the suction face of turbine blade 151 that causes separations and additional losses. The rear suction face 158 is affected by low Re conditions when the low energy and slowing BL separates, and this loss has been the primary focus of prior art turbine blade flow improvements which have focused on the blade rear after TE shock 157.

[0140] Suction face LE suction CVG array 152 on all the blades generate surface streaming tip vorticity on the blades that ensure that the suction BL is more fully energized from the CVG tips back to the blade TE 154, and this ensures that all the loss and separation mechanisms like; negative jet 156, TE shock 157, surface disruptions, premature bypass transition, Klebanoff streaks and low Re separation bubbles are mitigated, unlike the prior art. LE pressure CVG array 153 is configured on the blade pressure faces and the streaming tip vortices act to minimize Taylor-Gortler (TG) vortices flow loss and also help to disrupt the transient wakes at impact point 155. Both LE suction CVG array 152 and LE pressure CVG array 153 may be optionally fabricated with asymmetric CVG step lengths so as to sum a particular vorticity direction into the blade TE and hence influence the TE exit flow conditions and total blade lift. FIG. 8 shows compressor blade 160 and compressor blade 161 in a cascade. The stagger of the blades LE's is opposite for the turbine cascade example in FIG. 7 since this compressor cascade is designed to induce velocity in a fluid-flow; and so the blade angles are effectively reversed and the cascade imparts energy to the fluid-flows. Incoming compressor freestream flow 162 enters at the operating inlet flow incidence angle and then exits as the compressor outlet freestream 166, after undergoing the blade turning angle and increasing the fluid-flow kinetic energy. Incoming compressor blade wake transient 168 enters at the inlet flow angle and meets the LE of blade 161 and is partially reflected back to blade 160. Compressor shock line 163 on the suction face is due to the influence of the adjacent blade 161, and since the fluid-flow is not generally accelerating in the passage overlap after the initial LE acceleration, the compressor blade suction face separation is a primary performance limiting condition that can lead to; local blade stalling, synchronous blade passage stall cells, flow breakdown and compressor surge.

[0141] Compressor LE suction CVG array 164 is added to all the blade suction sides and streams tip vorticity into the compressor shock line 163 to lower the shock losses and separations, as well as generally improving the blade suction face BL energy, and allowing a larger designed compressor turning angle before discharge into a downstream diffusing stator set that induces pressure recovery into the slowing fluid flow. Compressor LE pressure CVG array 165 is added to all the blade pressure faces and streams tip vorticity along the blade pressure face to minimize flow losses and TG vortices, and also allow a greater blade turning capability, allowing axial compressor designs with fewer stages and lower weight and costs. As for the turbine blade, the compressor CVG arrays may be optionally fabricated with asymmetric CVG step lengths so as to sum a particular vorticity direction into the blade TE and hence influence the TE exit flow conditions and total blade lift. These CVG general arrangements herein are taught in the parent application that is incorporated by reference. Shock mitigation by CVG's taught here is applicable and configurable for fluid-flow shocks on a; wing, nacelle, fuselage, bypass-fan, compressor, rotor foil, stator foil, propeller, fluid-flow ducting, combustor or a turbine.

[0142] FIG. 9 shows a foil section 70 that is configured with interrupted CVG 71 instances at the LE so as to improve a deep dynamic stall Cm condition. Induction groove 72 is configured as being surrounded by steps with varying local angles so the high velocity LE local freestream local fluid-flow direction 74 in the LE BL region crossing this groove at an angle forms an up-flow travelling step vortex 75 over an AFS which then continues rearwards as for any CVG in e.g. FIG. 4. In this case there is no forward CVG valley 73 located behind the TE and in fact the left side of induction groove 72 is configured so that a portion of the fluid flow on the suction side of the LE stagnation point is intercepted and streamed back to interrupted CVG tip 77 to then stream as half of an intense sub-BL streamwise contra-rotating vortex filament pair. On the right or down-flow area of induction groove 72 the fluid-flow crosses this now down-flow partially forward-facing step 76 and also produces a step vortex that will travel rearwards and carry off vortex fluid-flow and momentum to the second interrupted CVG tip 78. These two step flows are retained over a wide range of foil AoA, and in the deep dynamic stall condition allows fluid flow to continue around the LE on the suction face and then stream back as a partial CVG streaming vortex effect, and help to break up the strong spanwise LE vortex suction that leads to the deep dynamic-stall high Cm condition. For normal non-dynamic stall or unstalled AoA operation the fluid flows operate as for an e.g. FIG. 4 CVG, and induction groove 72 operates as an upstream form of CVG valley 73 and the rearward CVG step sections operate as before. In this case there is no interrupted CVG material to protect the LE of the foil in CVG valley 73, so these CVG structure arrays would be placed on a sub-layer of material that can provide e.g. erosion protection etc. The edge shape and geometry of induction groove 72 is dictated by the local LE flow, and on a helicopter or swept wing a significant cross-flow to the local freestream local fluid-flow direction 74 is present and is taken into account in the design.

[0143] Other LE modification technologies have been attempted like the bio-inspired Blue-whale pectoral fin LE Tubercule, such as Pankl Aerospace Inc. has mimicked on sculpted helicopter rotor blades, or the DLR LEVogs that place a turbulence generator around the blade LE stagnation point. Both of these LE modifiers are not very effective at improving deep dynamic stall and shock loss and drag reductions are not in the range possible with CVG's.

[0144] FIG. 10 shows a cross sectioned oblique view of a US National Spaceplane type civil hypersonic scramjet powered partially air-breathing vehicle, so features are more easily seen. The vehicle body 110 has a high speed aerodynamically sharp body leading edge 111 that forms a strong bow oblique shock 113 at hypersonic speeds that surrounds the whole vehicle and is partly employed as the first compression shock to slow down impinging rarefied atmosphere and help direct it via a fore-body shock ramp 132 and its reflected second shock 114 to the scramjet inlet lip 112 for processing.

[0145] This Waverider type body with vertical stabilizer 119 is designed to operate from low Mach numbers at takeoff from conventional horizontal runways and accelerate thru transonic flight and on to high supersonic speed (Mach 4+) employing a combined-cycle engine method based on e.g. an internal Turbofan engine etc., as well as a scramjet at higher speeds.

[0146] Above M4.0 a scramjet compression inlet may be started to enable hypersonic flight regimes, where the scramjet can now be employed for thrust. At takeoff at about M0.25 the body operates as a partial delta-winged aircraft, and lift at low speed moderate angle of attack (AoA) regimes in the dense lower atmosphere is provided by upper LE suction-face vortices of the delta wing and some body dynamic bottom face positive pressure. At high speed (e.g. M4 to M9+) and/or lower AoA the vehicle typically operates as a Waverider type of vehicle using mostly bottom surface dynamic impact pressures to generate balancing lift force. At hypersonic speeds this civilian NASP vehicle can follow a flight path that allows atmospheric exit and use a combined-cycle jet engine/rocket mode to accelerate to Low Earth Orbit (LEO) as an SSTO vehicle, or skip across the top of the e.g. stratosphere and be a sub-orbital high speed civil transport.

[0147] An equivalent type of angled delta Slat slot 131 can be provided for low speed enhanced lift operation that opens a path to allow selective fluid-flow from the underside pressure face into the central portion of the suction face. EVG's as for a regular Slat slot exit as in FIG. 3 are added on the rear exit slat slot face, and these perform the; Slat slot sealing and fluid-flow attachment functionality since they are not subjected to high speed hot fluid-flows. Delta Slat slot 131 is shown as angled from the centerline along slot edge line 133 and terminates before the swept LE sections that have the low speed vortex lifting sections on the top surface (not shown).

[0148] Scramjet engine 117 is configured as a duct system, with an initial isolator section that processes the initial lip oblique shock 115 and further reflects multiple compression shocks down this isolator section to slow down and compress the fluid flow to near sonic speeds upon reaching the vicinity of fuel injection pylon 116. After fuel is added into a compressed and near sonic flow, combustion occurs in the rear of the duct in the combustor section 130 and then the exhaust fluid flow is expanded and accelerated by the aft body expansion surface 125, and the fuel enthalpy is released that provides energy to overcome the vehicle entropy losses and sustain speed.

[0149] After scramj et inlet starting a major challenge is to maintain flow stability in the cascaded and interrelated hypersonic-supersonic-transonic flows. The isolator and combustor sections are limited in flow capacity by thermal flow choking and additionally any BL flow separations in these sections. Correct isolator operation as supersonic flow ensures that any pressure changes in the downstream and combustor sections are not transmitted upstream to cause problems with the inlet conditions. If the downstream section flows drop below Mach 1.0 then a terminal normal shock is present and the subsequent flows interact because pressure perturbations can flow in any direction.

[0150] Because the isolator and combustor walls have BL flows with the closest wall portion below the sonic line, this presents a thin channel by which downstream pressure changes and flow state information will leak back up the isolator section. In particular the isolator oblique shocks all interact with the surface BL and induce uncontrolled SWBLI separations when the shocks are strong. This causes the effective duct cross section to decrease and tend to cross-section flow choking, and it is possible for these flow perturbations to cascade back up this otherwise isolated volume and cause the ideal shock on lip inlet conditions to change adversely. This feedback cycle can be unstable, hysteretic and lead to inlet unstart and/or engine damage. To stabilize the isolator and combustor BL duct flows, isolator entry CVG array 122 and combustor entry CVG array 123 and side wall CVG array 126 are added around the duct walls and these are configured ahead of the nominal design shock locations to help suppress the shock induced BL separations, and are configured in size and height as acting mostly below the sonic line of the BL. Since the velocity and shock profiles change with vehicle speed, it is possible to have a number of cascaded CVG arrays on the duct walls that help control SWBLI over a predetermined duct section irrespective a of exact shock locations, so that the ducting is desensitized to fluid flow velocity changes that occur naturally in operation, so flow choking is then mainly limited by thermal effects.

[0151] Inlet turn CVG array 121 is provided before the upper edge of the inlet to provide BL stabilization on the transition from the fore-body shock ramp 132 into the isolator ducting to ensure separation free BL at this transition, whether sharp edged or a curved surface. By having multiple CVG arrays around the whole duct section wall circumference the problem with rectilinear or round duct corners of flow separation roll-over, slewing and detachment is eliminated.

[0152] Fuel injection pylon 116 may employ a pylon mixing CVG array 127 to add controlled intense mixing vorticity adjacent to fuel injection port 128 to improve combustion speed and uniformity without adding significant drag. As an alternative to the flow-disrupting fuel injection pylon 116 it is possible to modify combustor entry CVG array 123 with an increased step height and with fuel injection ports (as for the removed pylon) that then efficiently mix in the fuel along the CVG rear facing step edge and support combustion. The CVG step edge stagnation points below the BL sonic line allow flame-holding to occur to stabilize combustion. Combustor exit CVG array 124 is provided to help stabilize the exiting flow BL across aft body expansion surface 125 and onto the final exit face 118 at the final freestream velocity and ambient pressures. A leading edge CVG array 120 may be added near the body leading edge 111 to stabilize the early BL development and may also employ gas injection ports behind the CVG array steps to allow addition of BL cooling or modifying gasses such as carbon monoxide to change local flow density or introduce pre-combustion gases initially below the sonic line that flow down the ramp surface and into the engine inlet duct. Slot edge line 133 present an angled surface discontinuity that may generate a weak oblique shock that propagates to meet the bow oblique shock 113 at meeting point 135 as an Edney class VI shock interaction that slightly modifies this bow shock geometry.

[0153] The initial slot edge may be expanded as a larger groove to generate a larger travelling edge vortex-flow along the slot edge with a larger mass of fluid-flow entrained and so increase the related oblique shock and its effect on the bow shock position. The vortex flow along Slot edge line 133 may be rapidly varied by flow modulator 134 means which may be implemented by a vortex transverse; mechanical flow gating device, a gas injection device or a plasma actuator that acts to control the vortex and its size and hence level of shock generation. This provides a fast and fine trimming method for ensuring the shock on inlet flow condition.

[0154] These surprisingly diverse ranges of types of embodiments as taught herein to improve drag by shock loss mitigation, and device fluid-flow and energy efficiency improvements are an unexpected outcome and capability of fundamentally integrated CVG and eVG applications that are simply not practical or possible with conventional prior art Vortex Generator or flow control approaches. All the cited embodiments and variations, and extensions to cover varying application instances and areas, at their most fundamental common level, employ novel configurations of Conformal Vortex Generator art and/or eVG art to process or manipulate Newtonian fluid-flows to obtain a level of benefits such as improved energy efficiency and/or expanded control ranges, not possible with prior art.

[0155] Therefore, while the disclosed information details the preferred embodiments of the invention, no material limitations to the scope of the claimed invention are intended and any features and alternative designs that would be obvious to one of ordinary skill in the art are considered to be incorporated herein. Consequently, rather than being limited strictly to the features disclosed with regard to the preferred embodiment, the scope of the invention is set forth and particularly described in the following attached claims.