Aircraft or spacecraft fluidic oscillator device
10647416 ยท 2020-05-12
Assignee
Inventors
- Karin BAUER (Oberhaching, DE)
- Markus Blechschmidt (Munich, DE)
- Sebastian Schwarz (Munich, DE)
- Peter Langenbacher (Munich, DE)
Cpc classification
F05B2210/30
MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
B64C21/02
PERFORMING OPERATIONS; TRANSPORTING
Y02T50/10
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
B64C21/02
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A fluidic oscillator device, in particular for a or in a flow control system for an aircraft or spacecraft, has a first and a second fluidic actuator, wherein each of the actuators has an inlet for supplying pressure and a first and a second outlet, from which an actuator flow can be discharged. The device further has a fluidic control for controlling an oscillating discharge of the actuator flow from the first and second outlet of the actuators, wherein the control has a connection portion which is arranged between the first actuator and the second actuator.
Claims
1. An aircraft or Spacecraft fluidic oscillator device for or in a flow control system, the device comprising: a first fluidic actuator and an adjacent second fluidic actuator, wherein each of the actuators has an inlet for supplying pressure and a first and a second outlet, from which an actuator flow is discharged; and a fluidic control for controlling an oscillating discharge of the actuator flow from the first and second outlet of the actuators, wherein the control has a connection portion configured as a flat part which is arranged between the first actuator and the second actuator, wherein the control is devoid of a feedback line external to the connection portion.
2. The fluidic oscillator device of claim 1, wherein the control comprises a control channel in each actuator, wherein a control flow, which is guided through the control channel, determines a respectively active outlet of the actuator, wherein the control channels at the actuators respectively have first and second junctions and wherein the connection portion has a first and a second connection channel which fluidically interconnect the junctions of the control channels.
3. The fluidic oscillator device of claim 2, wherein the connection portion also has a bypass channel which provides a fluidic connection between the first and the second connection channel and is configured such that the actuators and the control are operated at a common oscillation frequency.
4. The fluidic oscillator device of claim 2, wherein one or both of the actuators are configured as flat parts with opposing planar faces.
5. The fluidic oscillator device of claim 4, wherein the flat parts are stacked in a direction perpendicular to the planar faces in a force-locking manner.
6. The fluidic oscillator device of claim 4, wherein the bypass channel is configured as a groove which is introduced into the connection portion.
7. The fluidic oscillator device of claim 6, wherein the groove runs in a first planar side and in a second planar side of the connection portion, a passage being provided through the connection portion.
8. The fluidic oscillator device of claim 2, wherein the bypass channel comprises at least one curve.
9. The fluidic oscillator device of claim 8, wherein the bypass channel comprises a plurality of curves which are arranged in a serpentine-like manner.
10. The fluidic oscillator device of claim 4, wherein the first junction of the control channel is arranged on a first planar face of the respective actuator and the second junction of the control channel is arranged on a second planar face of the respective actuator.
11. The fluidic oscillator device of claim 2, wherein the first junction of the control channel of the first actuator is connected by the first connection channel of the connection portion to the first junction of the control channel of the second actuator.
12. The fluidic oscillator device of claim 11, wherein the second junction of the control channel of the first actuator is connected by the second connection channel of the connection portion to the second junction of the control channel of the second actuator.
13. The fluidic oscillator device of claim 11, wherein the first connection channel leads through the connection portion in a first planar side of the connection portion.
14. The fluidic oscillator device of claim 12, wherein the second connection channel leads through the connection portion in a second planar side of the connection portion.
15. The fluidic oscillator device of claim 2, wherein the first junction of the control channel of the first actuator is connected by the first connection channel of the connection portion to the second junction of the control channel of the second actuator.
16. The fluidic oscillator device of claim 15, wherein the second junction of the control channel of the first actuator is connected by the second connection channel of the connection portion to the first junction of the control channel of the second actuator.
17. The fluidic oscillator device of claim 15, wherein the first connection channel leads through the connection portion from a first planar side of the connection portion to a second planar side.
18. The fluidic oscillator device of claim 16, wherein the second connection channel leads through the connection portion from the second flat side of the connection portion to the first flat side.
19. The fluidic oscillator device of claim 1, wherein at least a third fluidic actuator and at least a second connection portion are provided, wherein the second connection portion is arranged between the second actuator and the third actuator and fluidically interconnects them.
20. The fluidic oscillator device of claim 19, comprising a plurality of further fluidic actuators and a plurality of further connection portions, wherein a respectively one of the further connection portions is arranged between respectively two of the further actuators and fluidically interconnects them.
21. The fluidic oscillator device of claim 1, wherein, for at least one of the actuators, one of the first or the second outlet has a start outlet configuration which allows the actuator flow to discharge at least mainly through the one outlet at a beginning of a pressurization of the actuator.
22. The fluidic oscillator device of claim 21, wherein the start outlet configuration comprises a lower fluidic resistance than the configuration of the other outlet of the actuator.
23. The fluidic oscillator device of claim 22, wherein the start outlet configuration comprises a larger passable cross section than the configuration of another outlet of the actuator.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) In the drawings:
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(29) In the figures, the same reference signs denote identical or functionally identical components, unless indicated otherwise.
DETAILED DESCRIPTION
(30)
(31) The oscillator device 1 has a first fluidic actuator 2, a second fluidic actuator 3 and a connection portion 8 arranged between the fluidic actuators 2, 3.
(32) The fluidic actuators 2, 3 have a respective inlet 4, via which the respective actuator 2, 3 is supplied with pressure. Furthermore, the first actuator 2 has a first outlet 5A and a second outlet 5B. Likewise, the second actuator 3 has a first outlet 6A and a second outlet 6B. An actuator flow can be discharged through the outlets of the actuators 2, 3.
(33) Provided in each of the actuators 2, 3 is a control channel 9 which acts as part of a fluidic control 7 and through which a control flow can be guided. The fluidic control 7 further comprises the connection portion 8 and serves to control an oscillating discharge of the actuator flow from the first and second outlets 5A, 5B and 6A, 6B of the actuators 2, 3. In this respect, the control flow determines which of the first and second outlets 5A, 5B and 6A, 6B of the respective actuator is active in each case.
(34) The control channels 9 respectively have a first junction 10A, 11A and a second junction 10B, 11B. Furthermore, the connection portion 8 has a first connection channel 12A and a second connection channel 12B. The junctions 10A, 10B, 11A, 11B of the control channels 9 are fluidically interconnected by these connection channels 12A, 12B.
(35) In the embodiment shown, the first connection channel 12A fluidically connects the first junction 10A of the control channel 9 of the first actuator 2 to the first junction 11A of the control channel 9 of the second actuator 3. The second connection channel 12B fluidically connects the second junction 10B of the control channel of the first actuator 2 to the second junction 11B of the control channel 9 of the second actuator 3. The control channels 9 of the first and second actuators 2, 3 are thus connected in parallel with one another.
(36) This means that an excess pressure or a vacuum respectively prevails in parallel in the control 7 in the same area of the control channels, so that in each case the first outlets 5A, 6A or the second outlets 5B, 6B of the actuators are simultaneously active. Arrows show a simultaneous activity of the second outlet 5B of the first actuator 2 and of the second outlet 6B of the second actuator 3.
(37)
(38) Here, in contrast to the embodiment according to
(39) This diagonal or crossover connection is realized in that the first connection channel 12A fluidically connects the first junction 10A of the control channel 9 of the first actuator 2 to the second junction 11B of the control channel 9 of the second actuator 3. The second connection channel 12B fluidically connects the second junction 10B of the control channel 9 of the first actuator 2 to the first junction 11A of the control channel 9 of the second actuator 3.
(40) As a result, an excess pressure or vacuum respectively prevails in the control 7 on the opposite side of the control channels 9 of the respective actuators 2, 3. Opposite outlets 5A, 6B or 5B, 6A of the two actuators 2, 3 are thus respectively simultaneously active. Arrows show a simultaneous activity of the second outlet 5B of the first actuator 2 and of the first outlet 6A of the second actuator 3.
(41)
(42) The interconnection of the inlets 4 is schematically shown in addition to the interconnection of the connection portion 8. The inlets are connected to a common pressure source 19.
(43) Here, the actuators 2, 3 are shown in cross section, it being possible to see the internal course of the flow channels and of the control channel 9. In the following, the course is described by way of example based on the first actuator 2, both actuators being of an identical construction.
(44) The first junction 10A of the control channel 9 of the first actuator 2 is arranged on a first side of the actuator 2 and the second junction 10B of the control channel 9 is arranged on a second side of the actuator 2.
(45) An inlet 4 for supplying pressure to the actuator 2 is arranged in the centre of the actuator 2. The inlet 4 runs into a common chamber 17 which is traversed by the control channel 9 and out of which lead the first and second outlets 5A, 5B of the actuator 2 in different directions with an opposite transverse component. The first outlet 5A runs out of the chamber with a direction component oriented to the left in the drawing, while the second outlet 5B runs out of the chamber with a direction component to the right.
(46) The chamber 17 contains a deflector device 18 for deflecting a pressure supply flow which enters centrally through the inlet 4, so that after deflection, an actuator flow issues through one of the outlets 5A, 5B.
(47) A respective convex widening 24 is provided in the course of the outlets 5A, 5B. This widening serves to homogenise the actuator flow or jets which are discharged from the respective outlet.
(48) During operation, the pressure supply flow generates a vacuum in the control channel 9, thereby causing a fluidic oscillation of the control 7. Due to this oscillation of the control 7, a control flow which flows in the control channel 9 changes its flow direction in a regularly oscillating manner. For this, the control flow passes transversely through the chamber 17 and, subject to the flow direction of the control flow, thus determines the respectively active outlet. For this purpose, the control flow deflects the pressure supply flow sufficiently to cause a deflection for the pressure supply flow into the first outlet 5A or into the second outlet 5B. An actuator flow thus issues in an oscillating manner alternately through the first outlet 5A or through the second outlet 5B.
(49) In the embodiment shown here, the control 7 is also formed with the control channels 9 and the connection portion 8. As in the embodiment according to
(50) Also in this embodiment, the connection portion 8 has a bypass channel 13 which provides a fluidic connection between the first connection channel 12A and the second connection channel 12B. The bypass channel 13 is provided to allow an in-phase oscillation of the actuators 2, 3. For this purpose, the connection of the connection channels 12A, 12B via the bypass channel 13 has a configuration, in particular a corresponding length and/or a corresponding volume, which allows an in-phase fluidic oscillation of the system of the entire control (with control channels, connection channels and bypass channel) without a time offset.
(51)
(52) The two actuators 2, 3 and the interconnection of the inlets 4 are configured in the same way as described with respect to
(53) The interconnection of the connection portion 8 differs here in that the connection channels 12A, 12B of the connection portion 8, as in the embodiment according to
(54)
(55) In the embodiment shown here, the oscillator device contains a first actuator 2, a second actuator 3 and a connection portion 8 arranged between the actuators. Furthermore, end plates or connection plates 22 outwardly covering the actuators 2, 3 are provided.
(56) Here, the actuators 2, 3 and the connection portion 8 are configured as flat parts which can be stacked together and can be connected in a force-locking manner by connecting bolts. Through-holes 23 are provided in the end plates or connection plates 22, in the actuators 2, 3 and in the connection portion 8 for the force-locking connection.
(57) The bypass channel 13 is introduced as a groove 14 into the connection portion 8 configured as a flat part, which will be described in more detail with reference to
(58) Furthermore, a nozzle arrangement 20 is provided which provides a canalization of the actuator flow to be discharged as a thin, linear flow or jet through an outlet slit 21. A number of outlet slits 21 is provided which corresponds to the number of outlets of the oscillator device, here, four outlet slits 21.
(59) The nozzle arrangement 20 is configured to be attached on the end face of the force-locking assembly of actuators 2, 3, connection portion 8 and end plates or connection plates 22 which has the outlets 5A, 5B, 6A, 6B. The nozzle arrangement 20 can also be integrated into the surface of a flow body of an aircraft or spacecraft to realize a flow control system.
(60)
(61) The outlets of the oscillator device 1 which are active in the first state are shown here schematically by arrows emanating from the outlet slits 21, the second outlets 5B, 6B being active, holding phase in the same direction. This is realized by a connection portion 8 which connects the control channels 9 of the actuators 2, 3 in parallel.
(62) The first state is, for example, a state with an oscillation phase angle of 0.
(63)
(64) A flow velocity profile of this type is also known as a blow-out pattern and is created by the hot wire or heating wire measuring method, also known as hot wire anemometry. For this purpose, a thin metal wire which is attached to a test head of an oscillator device 1 is heated by a constant temperature anemometer to a measurement temperature which is significantly above the temperature of the fluid or air of the issuing actuator flow. The resistance of the thin wire depends greatly and almost linearly on the temperature of the wire. In this respect, the temperature of the wire is a function of the flow velocity v due to cooling effects by convection. When the hot wire is cooled, what is known as a Wheatstone Bridge in the test setup increases the voltage present on the wire to restore the measurement temperature. The change in voltage which can be measured in this way is in particular directly proportional to the change in the flow velocity v.
(65) If a multiplicity of such measurements are made over a field of measurement points, for example 4040 measurement points, a velocity profile which is shown here can be derived therefrom. The measurement can be carried out, for example, using a measuring device which is positioned across several phases at the different measurement points.
(66) Here, the flow velocity profile is shown at a first oscillation phase angle of for example 0. For example, a flow velocity profile of this type can be measured at the oscillator device with an oscillation frequency of 275 Hz and a volume flow of 120 litres per minute.
(67) It can be seen that the two second outlets 5B, 6B, indicated by arrows in
(68)
(69) In this respect, the oscillation phase angle is offset by half a phase compared to the first state, for example 180.
(70) The active outlets of the oscillator device 1 are shown schematically here by arrows emanating from the outlet slits 21, the first outlets 5A, 6A being active, holding phase in the same direction.
(71)
(72) Here, the flow velocity profile is shown at the second oscillation phase angle, for example 180. It can be seen that the two first outlets 5A, 6A, identified by arrows in
(73)
(74) According to the embodiment shown here, a diagonally interconnected connection portion 8 which is different from
(75) A discharge thus respectively takes place simultaneously at a first phase angle, for example 0, from the first outlet 5A of the first actuator 2 and from the second outlet 6B of the second actuator 3 and also at a second phase angle, for example 180, at the same time from the second outlet 5B of the first actuator 2 and from the first outlet 6A of the second actuator 3.
(76) The first state shown here represents the state of the first oscillation phase angle, which is for example 0.
(77)
(78) Accordingly, here the flow velocity profile is shown at the first oscillation phase angle, for example 0. It can be seen that the two outlets 5A, 6B, identified by arrows in
(79)
(80) In the second state which is shown, the oscillation phase angle is offset by half a phase compared to the first state, for example 180.
(81) The outlets of the oscillator device 1 which are active in the second state are shown schematically here by arrows emanating from the outlet slits 21, these being the second outlet 5B of the first actuator and the first outlet 6B of the second actuator.
(82)
(83) Accordingly here the flow velocity profile is shown at the second oscillation phase angle, for example 180. It can be seen that the two outlets 5B, 6A, identified by arrows in
(84)
(85) The connection portion 8 has a first connection channel 12A, a second connection channel 12B and a bypass channel 13.
(86) As described with reference to
(87) The first connection channel 12A is arranged in a first side A of the connection portion 8 and is configured as a through-hole. For this purpose, it is provided to fluidically connect a first junction 10A of a flow channel 9 of a first actuator 2 to a first junction 11A of a flow channel 9 of a second actuator 3.
(88) The second connection channel 12B is arranged in a second side B of the connection portion 8 and is also configured as a through-hole. For this purpose, it is provided to fluidically connect a second junction 10B of a flow channel 9 of a first actuator 2 to a second junction 11B of a flow channel 9 of a second actuator 3.
(89) The bypass channel 13 connects the two connection channels 12A, 12B and is configured as a groove 14 which is introduced, in particular milled, into the material of the connection portion 8, configured as a flat part. The groove 14 runs from the first connection channel 12A, with a plurality of curves 16 in a serpentine manner over the front side shown here. Furthermore, a passage 15 is provided, through which the bypass channel 13 continues in a rear side of the connection portion 8. The bypass channel thus runs from the first side A of the connection portion 8 along the front side and rear side to the second side B of the connection portion 8.
(90)
(91) It can be seen that the bypass channel 13 initially runs on the rear side also with a plurality of curves 16 in a serpentine-like manner over the rear side and finally arrives at the second connection channel 12B.
(92)
(93) The sectional line C passes through the second connection channel 12B which is arranged in the second side B of the connection portion 8 and is configured as a through-hole, and also passes through the opening 15. The course of the bypass channel 13 in the front side and rear side of the connection portion 8 configured as a flat part can also be seen.
(94)
(95) The sectional line D passes through the first connection channel 12A which is arranged in the first side A of the connection portion 8 and is configured as a through-hole. The course of the bypass channel 13 in the front side and rear side of the connection portion 8 configured as a flat part can also be seen here.
(96)
(97) Here, the connection portion 8 also has a first connection channel 12A, a second connection channel 12B and a bypass channel 13. Apart from a few geometric differences, the bypass channel 13 is substantially of the same configuration as described with reference to
(98) Here however, unlike the embodiment according to
(99) The first connection channel 12A runs along the front side, shown here, of the connection portion 8 from the first side A of the connection portion 8 to a centrally arranged lower passage 15A which is configured as a through-hole. From the lower passage 15A, the first connection channel 12A continues along the rear side of the connection portion 8 to the second side B of the connection portion 8. Consequently, the first connection channel 12A is provided to fluidically connect a first junction 10A of a flow channel 9 of a first actuator 2 to a second junction 11B of a flow channel 9 of a second actuator 3.
(100) The second connection channel 12B runs along the front side, shown here, of the connection portion 8 to a centrally arranged upper passage 15B which is configured as a through-hole. From the upper passage 15B, the second connection channel 12B continues along the rear side of the connection portion 8 to the first side A of the connection portion 8. Consequently, the second connection channel 12B is provided to fluidically connect a second junction 10B of a flow channel 9 of a first actuator 2 to a first junction 11A of a flow channel 9 of a second actuator 3.
(101) The bypass channel 13 respectively connects the two connection channels 12A, 12B on the first side A and, for this, is connected to the first connection channel 12A on the front side and to the second connection channel 12B on the rear side.
(102)
(103) The sectional lines C, D and E of the cross-sectional views which are described in the following are shown here.
(104)
(105) Sectional line C runs in the region of the first side A of the connection portion. As can be seen here, the two connection channels 12A and 12B are connected to the bypass channel 13. In this respect, the first connection channel 12A is connected to the bypass channel 13 on the front side, the second connection channel 12B being connected to the bypass channel 13 on the rear side.
(106)
(107) Sectional line D passes through the centre of the connection portion 8 and thus cuts through the lower passage 15A of the first connection channel 12A and through the upper passage 15B of the second connection channel 12B.
(108)
(109) Sectional line E runs in the region of the second side B of the connection portion 8 and cuts through the passage 15 of the bypass channel 13. It can be seen that the connection channels are not coupled to the bypass channel 13 on the second side B, but only on the first side A.
(110)
(111) The actuator which is shown can be a first actuator 2, a second actuator 3 or a further actuator of the oscillator device. The function of the actuator is the same as described with reference to
(112) Furthermore, the course of two outlets is shown here with the transition to the nozzle arrangement 20 and the course thereof as far as the outlet slits 21. In the region of the nozzle arrangement 20, the profile of the actuator flow changes from an approximately rectangular cross section to a slit-shaped cross section. The convex widenings 24 in the outlets are provided to advantageously influence the actuator flow such that it has the greatest possible homogeneity at the outlet from the outlet slits 21. In this way, the effectiveness of the oscillator device can be improved, particularly when used in a flow control system.
(113) In the region of the nozzle arrangement 20, the outlets each have a diameter a1 and a2 of a passable cross section. The diameters a1 and a2 can differ slightly here. In this case, one of the outlets has a slightly larger passable cross section than the other. A difference of this type in the passable cross section also causes a slightly lower fluidic resistance of the larger outlet than in the case of the other outlet. In turn, the lower fluidic resistance of the outlet is a start outlet configuration which is provided to allow the actuator flow to issue through this outlet at the beginning of a pressurization of the actuator. Thus, the start outlet configuration is integrated into the nozzle arrangement attached to the actuator.
(114) At the beginning of the pressurization, the start outlet configuration defines a starting state of the actuator flow in which the actuator flow mainly issues from the outlet provided with the start outlet configuration. It is provided because at the beginning of the pressurization of the actuator, there is still no control flow in the control. The control flow is caused only by the pressure supply flow, with the control being set into fluidic oscillation.
(115) The position of the junctions of the control channel 9 is also shown here. They are located at the same height as the connection channels 12A, 12B according to
(116)
(117) This is a multipart nozzle arrangement 20 which has two outer parts 25, 27, a middle part 26 and two connectors 28. The individual parts of the nozzle arrangement can be produced, for example, by selective laser sintering, for example from polyamide. Other materials and other production processes are possible.
(118) The nozzle contour is introduced, in particular milled into the lateral surfaces of the outer parts 25, 27 and of the middle part 26. The outer parts 25, 27 and the middle part 26 can be interconnected in a force-locking manner, in particular they can be screwed together.
(119) The connectors 28 are configured to provide a connection between the nozzle arrangement 20 and the non-positively connected packet of actuators 2, 3 and connection portions 8. For this, the connectors 28 can be connected in a force-locking manner, for example screwed, in different directions to the nozzle arrangement 20 and to the packet of actuators 2, 3 and connection portions 8.
(120)
(121) The drawing shows two stacked packets, each with a first and a second actuator 2, 3, an interposed connection portion 8 and two outer end plates or connection plates 22 and one end plate or connection plate arranged between the packets, in particular between the second actuator of a first packet and the first actuator of a second packet.
(122) The oscillator device 1 can be expanded by any number of further packets.
(123)
(124) The oscillator device 1 shown here is based on the oscillator device 1 described with reference to
(125) Connection portions 8 which are connected according to
(126) In addition, a further expansion by one or more further connection portions and by one or more further actuators is possible.
(127)
(128) This figure shows the outlet slits 21 of the respective nozzle arrangements 20 of the parallel oscillator devices 1. Many different blow-out patterns can be generated by an appropriate configuration of the connection portions 8 with the parallel or downstream arrangement of the oscillator devices 1. Furthermore, coherent structures and influences on the air flow of the oscillator devices can also be investigated by a flow measurement.
(129) Although the present disclosure has been described above on the basis of preferred embodiments, it is not restricted thereto, but can be modified in many different ways.
(130) While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms comprise or comprising do not exclude other elements or steps, the terms a, an or one do not exclude a plural number, and the term or means either or both. Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.