JP2016200088A - Ejector, and high-altitude combustion test exhaust equipment having the ejector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ejector capable of sucking an object fluid efficiently and a high-altitude combustion test exhaust equipment having the ejector.SOLUTION: An ejector comprises: a pipe conduit having a curved section, in which an object fluid flows in a first direction; and a nozzle that is an annular passage covering the outer circumference of an end part of a first direction of the pipe conduit and arranged on the outer circumference of the pipe conduit, so that a drive fluid flows in a first direction. The conduit has a convex-concave shape, of which the radial position of the inner circumference of the end part varies in accordance with the circumferential position.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an ejector and a high-air combustion test exhaust system having the ejector.

  As a mechanism for sucking the target fluid flowing through the pipeline, an ejector that injects the drive fluid at a higher speed than the target fluid along the direction in which the target fluid flows into the pipeline through which the target fluid flows, and sucks the target fluid in the flow direction. There is.

  An ejector is used to reproduce a high-air environment with a very low atmospheric pressure in a combustion test of the rocket engine used for a rocket used in a space transportation system, corresponding to the upper stage (second stage or third stage) of the rocket. Used. Specifically, the fluid in which the exhaust gas is discharged from the rocket engine is sucked by the ejector, so that the atmosphere in which the exhaust gas from the rocket engine is injected is a space that simulates a high-air environment.

  As such an ejector, as shown in FIG. 4 of Patent Document 1 and Patent Document 2, an annular ejector in which a nozzle for injecting a driving fluid at a speed higher than the target fluid is annularly arranged on the outer edge of a pipeline through which the target fluid flows. There is. Patent Document 2 describes that irregularities are formed on the inner wall of a pipe line downstream of a position where high-speed driving fluid is ejected.

JP 59-151000 A JP 2003-4319 A

  Although the target fluid can be efficiently sucked by using the annular ejector, the performance can be further improved by sucking the target fluid more efficiently.

  This invention solves the subject mentioned above, and it aims at providing the ejector which can attract | suck an object fluid efficiently, and the high air combustion test exhaust equipment which has this.

  In order to achieve the above object, the ejector covers a pipe line having a curved cross section in which the target fluid flows in the first direction, and covers an outer periphery of the end of the pipe line in the first direction, An annular flow path disposed on the outer periphery, and a nozzle through which the driving fluid flows in the first direction. The pipe has a radial position on the inner peripheral surface of the end. It is characterized by a concavo-convex shape whose diameter changes according to.

  Moreover, it is preferable that the radial direction position of the internal peripheral surface of an edge part changes periodically along the circumferential direction, and the said pipeline is formed with several convex part in the circumferential direction.

  Moreover, it is preferable that the said pipe line has the uneven | corrugated | grooved part in which the said uneven | corrugated shape was formed in the said edge part side, and the straight pipe | tube part in which an internal peripheral surface becomes an ellipse or a circle in the said 1st direction upstream.

  Moreover, it is preferable that the said uneven | corrugated | grooved part has a transition part where the distance of an uneven | corrugated shaped recessed part and a convex part becomes small as it goes to the said 1st direction upstream.

  In the pipe, the concave and convex concave portions and convex portions of the inner peripheral surface gradually change in one circumferential direction along the first direction, and the concave and convex portions Preferably forms a helix.

  Further, it is preferable that the pipe has a circular cross section, and the nozzle has an annular shape.

  Moreover, it is preferable that the said pipe line is an uneven | corrugated shape from which the diameter of the outer peripheral surface of the said edge part changes a diameter according to the position of the circumferential direction.

  Moreover, it is preferable that the radial direction position of the outer peripheral surface of an edge part of the said pipe line changes periodically with the same period as the said internal peripheral surface along the circumferential direction.

  Moreover, it is preferable that the said nozzle is an uneven | corrugated shape from which the internal peripheral surface of the edge part of the said 1st direction downstream end changes a diameter according to the position of a radial direction in the radial direction.

  In the nozzle, the radial position of the inner peripheral surface of the end portion on the downstream side in the first direction may periodically change in the same cycle as the inner peripheral surface of the pipe along the circumferential direction. preferable.

  A downstream pipe line connected to an end portion of the outer peripheral surface of the nozzle in the first direction and through which the target fluid and the driving fluid flow downstream from the nozzle and the pipe in the first direction; It is preferable.

  The present invention is a high-air combustion test exhaust facility that houses a rocket engine and is connected to a low-pressure chamber into which combustion gas is injected, and into which the combustion gas flows, and is connected to the low-pressure chamber and flows in the flow direction of the combustion gas A diffuser having a throat portion that is guided along the throat portion, and an enlarged portion that is provided downstream of the throat portion and whose flow passage cross-sectional area increases toward the downstream side in the flow direction of the combustion gas, and is installed in the throat portion The ejector according to any one of the above, wherein the ejector ejects driving fluid along the flow direction to the throat portion, wherein the throat portion becomes a part of the pipe line, and the throat portion The driving fluid is ejected from the nozzle.

  ADVANTAGE OF THE INVENTION According to this invention, the ejector which can attract | suck an object fluid efficiently, and the high air combustion test exhaust equipment which has this can be provided.

FIG. 1 is a schematic diagram showing a schematic configuration of a rocket engine high-air combustion test facility according to the present embodiment. FIG. 2 is a cross-sectional view showing a schematic configuration of the annular ejector. FIG. 3 is a view of the annular ejector as viewed from the downstream side in the flow direction. 4 is a cross-sectional view taken along lines AA and BB in FIG. FIG. 5 is a cross-sectional view showing another example of an annular ejector. FIG. 6 is a cross-sectional view showing an annular ejector of another example. FIG. 7 is a cross-sectional view showing another example of an annular ejector. FIG. 8 is a view of another example of an annular ejector as viewed from the downstream side in the flow direction. FIG. 9 is a view of another example of an annular ejector as viewed from the downstream side in the flow direction. FIG. 10 is a view of another example of the annular ejector as viewed from the downstream side in the flow direction. FIG. 11 is a view of another example of an annular ejector as viewed from the downstream side in the flow direction. FIG. 12 is a view of another example of the annular ejector as viewed from the downstream side in the flow direction. FIG. 13 is a perspective view of an inner tube of another example of an annular ejector.

  DESCRIPTION OF EMBODIMENTS Embodiments (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the constituent elements described below can be appropriately combined. The rocket engine high-air combustion test facility of the present embodiment is a test facility for a rocket engine that is a liquid oxygen (liquefied oxygen) / liquid hydrogen (liquefied hydrogen) engine used in, for example, a satellite launch vehicle. A rocket engine is an engine that injects high-temperature, high-pressure combustion exhaust gas (hereinafter referred to as combustion gas) from an injection nozzle. The rocket engine high-air combustion test facility is a device for performing a rocket engine combustion test on the ground in such a high-air atmosphere such as outer space. The rocket engine is not limited to one using liquid fuel as a propellant, but may be a rocket engine using solid fuel as a propellant.

  FIG. 1 is a schematic diagram showing a schematic configuration of a rocket engine high-air combustion test facility according to the present embodiment. A rocket engine high-air combustion test facility 1 shown in FIG. 1 includes a low-pressure chamber 2 that houses a rocket engine 5, an exhaust device (high-air combustion test exhaust facility) 3 for depressurizing the low-pressure chamber 2, and a control device 4. Have. The exhaust device 3 serves as a combustion gas flow path. The rocket engine 5 is installed in the low pressure chamber 2 via a mount. In addition, a fuel supply device is connected to the rocket engine 5.

  The low-pressure chamber 2 is an airtight chamber, and the inside of the low-pressure chamber 2 can be set to a predetermined degree of vacuum by the exhaust device 3. For example, a vacuum pump 7 is connected to the low pressure chamber 2 for evacuation for maintaining a vacuum during the coasting of the reignition test of the rocket engine 5.

  The exhaust device 3 includes an exhaust tunnel 8 connected to the downstream side in the combustion gas flow direction F with respect to the low pressure chamber 2, and a muffler tower 9 provided on the downstream side of the exhaust tunnel 8. The exhaust tunnel 8 is provided on the most upstream side, and includes a diffuser 10 provided with an annular ejector (first ejector) 11 and a center body ejector (second ejector) 12 connected downstream of the diffuser 10. doing. That is, the exhaust device 3 of the present embodiment employs an exhaust system having a diffuser 10, a two-stage annular ejector 11, and a center body ejector 12.

  The diffuser 10 is connected to the downstream side of the reduction part 14 and the reduction part 14 gradually narrowing toward the downstream side in the combustion gas flow direction F, and the flow passage cross-sectional area is made constant along the combustion gas flow direction F. It has a throat portion (pipe) 15 and an enlarged portion 16 that is connected to the downstream side of the throat portion 15 and gradually increases toward the downstream side. That is, the flow path of the combustion gas is narrowed by the throat portion 15 and then expanded by the expansion portion 16. In addition, although the flow-path cross-sectional area of the throat part 15 was made constant, it does not need to be constant and the change of the cross-sectional area by design convenience shall be permitted. The cross-sectional area of the throat portion 15 is not completely the same along the longitudinal direction (combustion gas flow direction F), and slightly expands downstream from the installation position of the annular ejector 11.

  The annular ejector 11 is disposed in the vicinity of the inlet of the throat portion 15 of the diffuser 10 so as to be integrated with the diffuser 10. The annular ejector 11 includes a first ejector injection nozzle (injection port) 17 that injects steam as a driving fluid downstream from the inner peripheral surface (peripheral wall) 70 of the throat portion 15 of the diffuser 10 in the flow direction F of the combustion gas. A steam supply unit 18 for supplying steam to the one ejector injection nozzle 17, a steam pipe 19 for connecting the steam supply unit 18 and the first ejector injection nozzle 17, and a valve 20 provided in the steam pipe 19. doing. The relationship between the first ejector injection nozzle 17 and the throat portion 15 of the annular ejector 11 will be described later.

  A steam source such as an accumulator or a steam generator can be employed as the steam supply unit 18. The steam supply unit 18 also supplies steam to the center body ejector 12. Further, the driving fluid ejected from the annular ejector 11 and the center body ejector 12 is not limited to steam, and for example, nitrogen gas may be employed. The annular ejector 11 injects the steam supplied from the supply unit 18 via the steam pipe 19 toward the downstream side in the flow direction F of the combustion gas from the first ejector nozzle 17 into the throat unit 15, Combustion gas can be sucked in the flow direction F. The steam is injected at a speed higher than that of the combustion gas, for example, at a speed exceeding the speed of sound at the time of injection.

  The position of the annular ejector 11 in the flow direction F of the combustion gas is determined based on the position where the pressure recovery by the combustion gas injected from the rocket engine 5 occurs. Specifically, the position of the annular ejector 11 in the flow direction F of the combustion gas is disposed upstream of the position where the pressure recovery due to the combustion gas injection of the rocket engine 5 in the throat portion 15 occurs. In other words, the position is set on the upstream side of the annular ejector 11 so that pressure recovery of only the combustion gas of the rocket engine 5 does not occur.

  Here, as for the throat part 15, the 1st throat part 15a, the 2nd throat part 15b, and the 3rd throat part 15c are arrange | positioned from the flow direction F upstream. The first throat part 15 a is connected to the reduction part 14. The second throat portion 15 b is a portion on the downstream side of the first throat portion 15 a and is disposed on the downstream side of the first ejector injection nozzle 17 of the annular ejector 11. The second throat portion 15 b is connected to the first ejector injection nozzle 17. Further, the third throat portion 15c on the downstream side of the second throat portion 15b is reduced so as to have the same diameter as that of the first throat portion 15a as long as it does not interfere with the steam injection of the annular ejector 11. The cross-sectional area of the throat portions 15 b and 15 c on the downstream side of the first ejector injection nozzle 17 may be smaller than the cross-sectional area on the upstream side of the first ejector injection nozzle 17. That is, the throat portion 15 of the present embodiment is in the range of the distance S, and the first throat portion 15a, the third throat portion 15c, the first throat portion 15a, A second throat portion 15b that is slightly larger than the three throat portion 15c is included. Of course, the cross-sectional area along the flow direction F of the combustion gas in the range of the distance S may be constant.

  In the throat portion 15 of the diffuser 10, a block off valve (valve, gate valve) 23 capable of closing the flow path of the combustion gas is provided upstream of the annular ejector 11. The block-off valve 23 is a gate type valve. The block off valve 23 is a gate valve that can block the upstream side and the downstream side of the block off valve 23 in the diffuser 10 by closing the block off valve 23. Further, the diffuser 10 is provided with a bypass line 33 that bypasses the upstream side and the downstream side of the block-off valve 23. The bypass line 33 is provided with a bypass valve 34 that can shut off the bypass line 33. The block-off valve 23 is disposed upstream of the spray cooling device 27 that injects cooling water for cooling the combustion gas. The spray cooling device 27 will be described later.

  The diffuser 10 also has a diffuser wall surface cooling device 24. The diffuser wall surface cooling device 24 includes a first cooling water supply device 25 that supplies diffuser cooling water to the wall portion of the diffuser 10 that has a hollow structure, and an internal space of the wall portions of the first cooling water supply device 25 and the diffuser 10. The 1st cooling water piping 26 which connects these. When the diffuser cooling water supplied from the first cooling water supply device 25 is supplied to the wall portion constituting the diffuser 10, the wall surface of the diffuser 10 exposed to the high-temperature combustion gas is cooled.

  A spray cooling device 27 is provided near the downstream end of the diffuser 10. The spray cooling device 27 includes a cooling water nozzle 28 provided on the flow path of the diffuser 10, a second cooling water supply device 29 that supplies spray cooling water to the cooling water nozzle 28, a second cooling water supply device 29, and a cooling device. And a second cooling water pipe 30 connecting the water nozzle 28. The spray cooling device 27 is a device that sprays a predetermined amount of cooling water into the exhaust tunnel 8.

  The center body ejector 12 is disposed in the exhaust tunnel 8 and downstream of the diffuser 10. The center body ejector 12 includes a second ejector injection nozzle 32 disposed substantially in the center of the chamber as viewed from the flow direction F of the combustion gas, a steam supply unit 18 that supplies steam to the second ejector injection nozzle 32, and a steam supply. A steam pipe 19 connecting the section 18 and the second ejector injection nozzle 32, and a valve 20 provided in the steam pipe 19. In this embodiment, the annular ejector 11 and the center body ejector 12 share the steam supply unit 18.

  Next, the annular ejector 11 will be described with reference to FIGS. 2 to 3 in addition to FIG. FIG. 2 is a cross-sectional view showing a schematic configuration of the annular ejector. FIG. 3 is a view of the annular ejector as viewed from the downstream side in the flow direction.

  In the annular ejector 11, a first ejector injection nozzle 17 is disposed on the outer periphery of the first throat portion 15 a of the throat portion 15. The first ejector injection nozzle 17 is annularly provided in the circumferential direction on the wall surface of the throat portion 15 of the diffuser 10. The 1st ejector injection nozzle 17 uses the wall surface of the throat part 15 as a part of pipe line. The annular ejector 11 has a double tube structure in which the outer tube 50 is disposed on the outer periphery of the inner tube 100 at portions corresponding to the first throat portion 15 a and the first ejector injection nozzle 17. In the inner tube 100, the tip 56, which is the end on the downstream side in the flow direction, has a diameter smaller than that of the second throat portion 15b and is separated. Moreover, the diameter of the outer peripheral surface 72 becomes small and the front-end | tip 56 becomes a sharp shape as it goes to the flow direction downstream. In the outer tube 50, the diameter of the inner peripheral surface 74 becomes smaller toward the downstream side in the flow direction. That is, the distance between the outer tube 50 and the inner tube 100 becomes shorter as it goes downstream in the flow direction. The portion with the shortest distance between the inner tube 100 and the outer tube 50 on the distal end 56 side of the inner tube 100 is the choke portion 64. The outer pipe 50 has an end on the downstream side in the flow direction connected to the second throat portion 15b.

  Next, as shown in FIG. 3, the diameter of the inner tube 100 on the distal end 56 side of the inner peripheral surface 70 (the distance from the center to the inner peripheral surface 70) changes in diameter according to the position in the circumferential direction. It is an uneven shape. Specifically, the inner peripheral surface 70 has convex portions 80 and concave portions 82 alternately formed in the circumferential direction. Here, the convex portion 80 is a curved surface along the inner diameter 84 that is smaller than the central diameter 88. The recess 82 is a curved surface along the outer diameter 86 having a diameter larger than the central diameter 88. The inner peripheral surface 70 has a plurality of convex portions 80 and concave portions 82 formed in the circumferential direction having the same shape. Thereby, as for the internal peripheral surface 70, the position of the radial direction of an internal peripheral surface changes periodically along the circumferential direction.

  In the annular ejector 11, the inner pipe 100 serves as the throat portion 15 (first throat portion 15a, pipe line). In the annular ejector 11, the combination of the inner tube 100 and the outer tube 50 is a first ejector injection nozzle (nozzle) 17. In the annular ejector 11, a region surrounded by an inner peripheral surface 70, which is a radially inner surface of the inner pipe 100, becomes a combustion gas flow path (target fluid flow path) 52 through which the combustion gas 60 that is the target fluid to be sucked flows. . The combustion gas 60 flows along the axial direction of the inner tube 100. The annular ejector 11 has a ring-shaped region surrounded by an outer peripheral surface 72 that is a radially outer surface of the inner tube 100 and an inner peripheral surface 74 of the outer tube 50, and a steam flow through which steam 62 that is a driving fluid flows. A path (driving fluid flow path) 54 is formed. The steam 62 is injected from the choke portion 64 having the shortest distance between the inner tube 100 and the outer tube 50 on the distal end 56 side of the inner tube 100 toward the second throat portion 15b.

  In the annular ejector 11, the outer peripheral shape of the combustion gas 60 injected from the inner pipe 100 is uneven by forming an uneven shape in which the convex portions 80 and the concave portions 82 are alternately arranged in the circumferential direction on the inner peripheral surface 70. It can be a certain shape. Thereby, it can be made longer than the inner peripheral length of a pipe line. Thereby, the area of the interface between the combustion gas 60 and the steam 62 can be made larger than when the inner peripheral surface 70 is a circle. Since the area of the interface can be increased, exchange of momentum between the combustion gas 60 and the steam 62 can be promoted. That is, the combustion gas 60 can be efficiently sucked downstream by the steam 62 in the flow direction. Thereby, the length of the annular ejector 11, specifically, the length S of the throat portion 15 can be shortened, and the entire apparatus can be miniaturized.

  In the inner peripheral surface 70, it is preferable that the radial position of the inner peripheral surface of the outer edge changes periodically along the circumferential direction, and a plurality of convex portions 80 (concave portions) 82 are arranged in the circumferential direction. By arranging a plurality of convex portions 80 (concave portions) 82 in the circumferential direction, the inner peripheral length can be made longer than the original pipe line, and the cross-sectional area can be suitably increased. Thereby, the suction force of the annular ejector 11 can be further increased.

  Next, the example of the shape in the axial direction of the uneven | corrugated | grooved part of an internal peripheral surface is shown. The annular ejector 11 may have a concavo-convex shape on the inner peripheral surface 100, that is, a shape in which the convex portion 80 and the concave portion 82 extend in the entire region in the axial direction, but may have the following shape.

  4 is a cross-sectional view taken along lines AA and BB in FIG. FIG. 4 shows the inclination angle larger than the actual angle for easy understanding of the inclination. The inner tube 102 of the annular ejector 11a shown in FIG. 4 has a straight tube portion 90 and an uneven portion 92 in a cross section parallel to the axial direction of the inner tube 102. The inner pipe 102 is arranged in the order of the straight pipe portion 90 and the uneven portion 92 from the upstream side in the flow direction, and the straight pipe portion 90 and the uneven portion 92 are connected. The inner tube 102 has an uneven portion 92 in a range of a distance L from the upstream end in the flow direction from the end 56 on the downstream side in the flow direction, that is, the end on the second throat portion 15b side. The portion on the upstream side from the distance L is a straight pipe portion 90.

  In the straight pipe portion 90, the radial position of the inner peripheral surface 70 is constant. In the present embodiment, the inner peripheral surface 70 is a circle. That is, the shape is not formed with irregularities. The uneven portion 92 is provided in a range including the tip 56, and the uneven shape is formed on the inner peripheral surface 70. The uneven part 92 includes a transition part 94 and an uneven part maintaining part 96. The transition part 94 has an end on the upstream side in the first direction connected to the straight pipe part 90, and an end on the downstream side in the first direction connected to the unevenness maintaining part 96. That is, the transition part 94 connects the straight pipe part 90 and the unevenness maintaining part 96. In the transition portion 94, the distance between the concavo-convex concave portion and the convex portion increases toward the downstream side in the first direction, that is, the distance between the concave and convex portion in the concavo-convex shape increases toward the upstream side in the first direction. It is a smaller shape. In the transition portion 94, the cross section of the inner peripheral surface of the end portion on the upstream side in the first direction is a circle, and the cross section of the inner peripheral surface of the end portion on the downstream side in the first direction is uneven. In the unevenness maintaining portion 96, the inner peripheral surface 70 has an uneven shape, and the depth of the unevenness is constant regardless of the position in the axial direction. That is, the same shape as the unevenness of the tip 56 extends.

  By providing the uneven portion 92 and the straight tube portion 90 in this manner, the inner tube 102 can reduce the processing range. This can facilitate manufacture. Moreover, it can suppress that the flow of combustion gas peels from an internal peripheral surface by providing a transition part.

  Moreover, it is preferable that the uneven | corrugated | grooved part 92 shall make inclination-angle (theta) 3 degrees or less with respect to the axial direction of the internal peripheral surface 70 of the part where the diameter of the transition part 94 changes. Thereby, it is possible to suppress the separation of air at the uneven portion 92.

  FIG. 5 is a cross-sectional view showing another example of an annular ejector. The inner tube 104 of the annular ejector 11b shown in FIG. 5 has a straight tube portion 90 and an uneven portion 92a. The uneven portion 92a has a shape in which the entire region becomes a transition portion, and the distance between the uneven portion of the uneven shape increases toward the downstream side in the first direction. That is, the depth of the unevenness continuously changes up to the tip 56. Thus, it is good also as a shape which does not provide the unevenness | corrugation maintenance part 96. FIG.

Moreover, in the said embodiment, although the radial position of the convex part 80 was made constant and the radial position of the recessed part 82 was changed with the position of the axial direction, it is not limited to this. FIG. 6 is a cross-sectional view showing an annular ejector of another example. The inner tube 106 of the annular ejector 11c shown in FIG. 6 moves radially outward as the position corresponding to the recess 82 in the circumferential direction goes downstream in the first direction, and the position corresponding to the protrusion 80 in the circumferential direction. Moves radially inward as it goes downstream in the first direction. The diameter of the inner peripheral surface of the straight pipe portion 90 is a diameter corresponding to the central diameter 88. In this way, the positions of both the concave portion 82 and the convex portion 80 may be changed. In this case, the angle θ ₁ formed by the slope formed by the convex portion 80 and the central axis is preferably 3 degrees or less. Thereby, flow separation can be suppressed.

  FIG. 7 is a cross-sectional view showing another example of an annular ejector. In the inner tube 108 of the annular ejector 11d shown in FIG. 7, the axial position of the tip 56 of the convex portion 80 and the tip 56a of the concave portion 82 are the same. Thus, the angle in the direction orthogonal to the axial direction of the distal end surface of the inner tube 108 may be changed so that the distal end has the same shape.

  In the above embodiment, since the area of the interface can be suitably increased, the convex portion 80 and the concave portion 82 are formed in a gear shape formed by arcs having different diameters and line segments connecting the arcs, but the present invention is not limited to this. FIG. 8 is a view of another example of an annular ejector as viewed from the downstream side in the flow direction. In the inner tube 100a of the annular ejector 11e shown in FIG. 8, the unevenness of the inner peripheral surface 70a is formed by a wavy line having a central diameter 88 as a center line, for example, a sin curve. In this case, the vertex on the radially inner side of the curve becomes the convex portion 80a, and the vertex on the radially outer side of the curve becomes the concave portion 82a. Thus, the uneven shape of the inner peripheral surface 70a may be formed with a curve. The inner peripheral surface may have a shape in which the position of the maximum diameter and the position of the minimum diameter are connected by a straight line.

  Moreover, in the said embodiment, although the unevenness | corrugation was formed in the internal peripheral surface of the inner tube | pipe 100, and the outer peripheral surface 72 of the inner tube | pipe 100 and the inner peripheral surface 74 of the outer tube | pipe 50 were made into the shape where a cross section becomes a circle, it is not limited to this. .

  FIG. 9 is a view of another example of an annular ejector as viewed from the downstream side in the flow direction. The inner tube 100b of the annular ejector 11f shown in FIG. 9 has irregularities formed on the inner circumferential surface 70, and irregularities are also formed on the outer circumferential surface 72a. The outer peripheral surface 72a has a concavo-convex shape in which the diameter changes in accordance with the position in the circumferential direction, and is formed alternately with the convex portions 120 and the concave portions 122 in the circumferential direction. The convex portion 120 and the concave portion 122 have a gear shape formed by arcs having different diameters and line segments connecting the arcs as in the convex portion 80 and the concave portion 82. Here, as for the outer peripheral surface 72a, the position of radial direction changes periodically with the same period as an inner peripheral surface along the circumferential direction.

  As described above, by forming irregularities on the outer peripheral surface 72a, irregularities can also be formed on the interface of the vapor 62. Thereby, the area of the interface between the combustion gas 60 and the steam 62 can be increased, and the effect of sucking the combustion gas 60 with the steam 62 can be further increased. Further, by periodically changing the uneven shape of the outer peripheral surface 72a at the same cycle as the inner peripheral surface, the relationship between the steam 62 and the combustion gas 60 at the circumferential position can be averaged.

  In the above embodiment, since the area of the interface can be suitably increased, the convex portion 120 and the concave portion 122 are formed in a gear shape formed by arcs having different diameters and line segments connecting the arcs, but the present invention is not limited to this. FIG. 10 is a view of another example of the annular ejector as viewed from the downstream side in the flow direction. In the inner tube 100c of the annular ejector 11g shown in FIG. 10, the unevenness of the inner peripheral surface 70a is formed by a wavy line having a central diameter 88 as a center line, for example, a sin curve. Similarly, in the inner tube 100c, the unevenness of the outer peripheral surface 72a is formed by a wavy line having a central diameter 88 as a center line, for example, a sin curve. In this case, the vertex on the radially inner side of the curve becomes the convex portion 120a, and the vertex on the radially outer side of the curve becomes the concave portion 122a. As described above, the concave and convex shapes of the inner peripheral surface 70a and the outer peripheral 72b may be formed by curves. The inner peripheral surface may have a shape in which the position of the maximum diameter and the position of the minimum diameter are connected by a straight line.

  FIG. 11 is a view of another example of an annular ejector as viewed from the downstream side in the flow direction. The inner circumferential surface 74a of the outer tube 50a of the annular ejector 11h shown in FIG. 11 has irregularities formed on the inner circumferential surface 70, and irregularities are also formed on the inner circumferential surface 74a. The inner peripheral surface 74a has a concave-convex shape in which the diameter varies in accordance with the position in the circumferential direction, and is formed alternately with the convex portions 130 and the concave portions 132 in the circumferential direction. The convex portion 130 and the concave portion 132 have a gear shape formed by arcs having different diameters and line segments connecting the arcs, like the convex portion 80 and the concave portion 82. Here, as for the inner peripheral surface 74a, the position of radial direction changes periodically with the same period as an inner peripheral surface along the circumferential direction.

  As described above, by forming irregularities also on the inner peripheral surface 74a of the outer tube 50a, it is possible to form irregularities also on the interface of the vapor 62. Thereby, the area of the interface between the combustion gas 60 and the steam 62 can be increased, and the effect of sucking the combustion gas 60 with the steam 62 can be further increased. Further, by periodically changing the uneven shape of the inner peripheral surface 74a at the same cycle as the inner peripheral surface, the relationship with the combustion gas 60 can be averaged with the steam 62 at the circumferential position.

  In the above embodiment, since the area of the interface can be suitably increased, the convex portion 130 and the concave portion 132 are formed in a gear shape formed by arcs having different diameters and line segments connecting the arcs, but are not limited thereto. FIG. 12 is a view of another example of the annular ejector as viewed from the downstream side in the flow direction. In the outer tube 50b of the annular ejector 11i shown in FIG. 12, the unevenness of the inner peripheral surface 70a is formed by a wavy line having a central diameter 88 as a center line, for example, a sin curve. Similarly, in the outer tube 50b, the unevenness of the inner peripheral surface 74b is formed by a wavy line having a central diameter 88 as a center line, for example, a sin curve. In this case, the vertex on the radially inner side of the curve becomes the convex portion 140, and the vertex on the radially outer side of the curve becomes the concave portion 142. As described above, the uneven shapes of the inner peripheral surface 70a and the inner peripheral surface 74b may be formed by curves. The inner peripheral surface may have a shape in which the position of the maximum diameter and the position of the minimum diameter are connected by a straight line.

  Moreover, it is preferable that the annular ejector forms irregularities whose radial positions change in the circumferential direction on all of the inner peripheral surface and outer peripheral surface of the inner tube 100 and the inner peripheral surface of the outer tube 50 at the tip portion and the choke portion. . Thereby, the area of an interface can be enlarged more. Further, the width of the choke portion can be made constant in the circumferential direction.

  FIG. 13 is a perspective view of an inner tube of another example of an annular ejector. In the inner tube 100c shown in FIG. 13, the positions of the concave and convex portions of the concave and convex shapes on the inner peripheral surface 70b gradually change in one direction along the first direction, and the concave and convex portions are A spiral is formed. That is, the concave portion 82b has a shape that changes in the circumferential direction. In the present embodiment, the recess 82b is inclined at an angle α with respect to a line parallel to the central axis 89 of the inner peripheral surface 70b. FIG. 13 shows only the position of one concave portion 82b, but the other concave portions and convex portions are also rotated in the circumferential direction. Thus, by making the concave portion and the convex portion into a spiral shape, the combustion gas can be rotated in the turning direction, and the exchange of kinetic energy can be further promoted.

  In the annular ejector of the present embodiment, the portion of the inner tube and the outer tube where the uneven portion is not formed, that is, the cross section perpendicular to the axial direction of the straight tube portion is a circle or a perfect circle. It is good. In the annular ejector, it is preferable that the inner tube and the outer tube have a shape in which a cross section perpendicular to the axial direction connects the curves.

  Next, an operation method of the rocket engine high-air combustion test facility 1 of the present embodiment will be described.

(Equipment starting method)
When the rocket engine high-air combustion test facility 1 is started, the low-pressure chamber 2 is set to a low pressure before the rocket engine 5 is started. Specifically, the ejector (annular ejector 11 and center body ejector 12) is operated with the block-off valve 23 in a closed state, and an exhaust process is performed in a region downstream of the block-off valve 23.

  On the other hand, the low pressure chamber 2 is evacuated through the bypass line 33 with the bypass valve 34 opened. Specifically, evacuation of the low pressure chamber 2 and the area upstream of the block-off valve 23 in the diffuser 10 is performed via the bypass line 33. Next, in a state where the low pressure chamber 2 is sufficiently low (for example, 100 Torr, 13332 Pa), the block off valve 23 is opened, the bypass valve 34 is closed, and the low pressure chamber 2 is further set to about 10 Torr (1333 Pa). Until low pressure.

  When the low pressure chamber 2 reaches 10 Torr, the rocket engine 5 is started and a combustion test of the rocket engine 5 is performed. At this time, downstream of the annular ejector 11, the pressure is recovered to subsonic speed so that the exhaust device 3 is differentially stabilized. And spray cooling is implemented in the downstream of the annular ejector 11, and the temperature of combustion gas is reduced.

(How to stop the equipment)
The operation when the rocket engine high-air combustion test facility 1 is stopped will be described. When the rocket engine high-air combustion test facility 1 is stopped, the control device 4 stops engine combustion with the annular ejector 11 and the center body ejector 12 being operated (rocket engine stop process). After the combustion gas discharged from the rocket engine 5 has completely flowed, the control device 4 issues a command for closing the block-off valve 23.

  When the rocket engine 5 stops, the ejector effect due to the combustion gas discharged from the rocket engine 5 disappears, and the combustion gas tends to flow backward to the low pressure chamber 2 side. However, the operation of the annular ejector 11 reduces the blowback in which the combustion gas tends to flow backward to the low pressure chamber 2 immediately after the rocket engine 5 is stopped. In other words, in the rocket engine high-air combustion test facility 1 according to the present embodiment, the annular ejector 11 is arranged upstream of the position where the pressure recovery due to the combustion gas injection of the rocket engine 5 occurs, thereby reducing blowback. The

  Further, the block-off valve 23 is closed with a slight delay (valve closing step). The block-off valve 23 is completely closed after blowback occurs after the combustion gas discharged from the rocket engine 5 completely flows. The block-off valve 23 blocks the upstream side and the downstream side in the throat portion 15 of the diffuser 10, thereby preventing blowback that occurs when the annular ejector 11 is stopped. Next, the control device 4 stops the two ejectors, the annular ejector 11 and the center body ejector 12 (ejector stop step). Next, the pressure in the low pressure chamber 2 is returned to atmospheric pressure.

  According to the embodiment described above, the annular ejector 11 is disposed in the throat portion 15 of the diffuser 10, whereby blowback when the rocket engine 5 is stopped can be reduced. That is, the ejector effect due to the combustion gas discharged from the rocket engine 5 with the stop of the rocket engine 5 disappears, and the combustion gas that is going to flow backward to the low pressure chamber 2 side can be pushed back by the annular ejector 11 in the downstream direction. .

  Further, by closing the block off valve 23 provided on the upstream side of the annular ejector 11, it is possible to prevent blowback that occurs when the annular ejector 11 is stopped. That is, even when the steam flows backward as the annular ejector 11 stops, the steam that flows backward can be blocked by the block-off valve 23.

  In addition, by installing the block-off valve 23 in the diffuser 10, the time required for evacuation of the low pressure chamber 2 and the area upstream of the block-off valve 23 in the diffuser 10 in the decompression process before starting the rocket engine 5 is shortened. can do. That is, the volume that is evacuated through the bypass line 33 can be reduced, and the time to reach the degree of vacuum before the test can be shortened. Furthermore, by installing the block-off valve 23 in the diffuser 10, it is possible to shorten the time required for evacuation when coasting the reignition test of the rocket engine 5 and to reduce the capacity of the vacuum pump 7.

  Further, since the annular ejector 11 is arranged upstream of the position where the pressure recovery due to the combustion gas injection of the rocket engine 5 is generated, the pressure recovery capability of the rocket engine 5 itself can be effectively utilized. , 12 can be reduced in steam consumption. Further, during the rocket engine combustion test, the wall surface cooling effect by the driving steam of the annular ejector 11 can reduce the heat load from the high-temperature combustion gas and reduce the required coolant flow rate.

  Further, by integrating the annular ejector 11 and the diffuser 10, the length required for the exhaust device 3 can be shortened as compared with a mode in which the ejector is disposed on the downstream side of the diffuser. Further, by disposing the first ejector injection nozzle 17 of the annular ejector 11 radially outside the inner peripheral surface 70 of the throat portion 15, the combustion gas of the rocket engine 5 collides with the nozzle during the rocket engine combustion test. It is possible to prevent the pressure recovery generated by.

  Further, by arranging the block-off valve (valve) 23 on the upstream side of the spray cooling device 27, it is possible to facilitate the evacuation as compared with the case where the valve is arranged on the downstream side of the spray cooling device 27. . That is, when the valve is arranged on the downstream side of the spray cooling device 27, the cooling water injected from the spray cooling device 27 is accumulated on the upstream side of the valve, and this cooling water evaporates when evacuating. , The increase in the degree of vacuum is suppressed. On the other hand, since cooling water does not accumulate, evacuation becomes easy.

  Although the embodiments of the present invention have been described in detail with reference to the drawings, the configurations and combinations of the embodiments in the embodiments are examples, and the addition and omission of configurations are within the scope not departing from the gist of the present invention. , Substitutions, and other changes are possible. Further, the present invention is not limited by the embodiments, and is limited only by the scope of the claims.

DESCRIPTION OF SYMBOLS 1 Rocket engine high-air combustion test equipment 2 Low pressure chamber 3 Exhaust device 4 Control device 5 Rocket engine 7 Vacuum pump 8 Exhaust tunnel 9 Silencer tower 10 Diffuser 11 Annular ejector 12 Center body ejector 14 Reduction part 15 Throat part (pipe)
16 Enlarged part 17 First ejector injection nozzle (injection port)
18 Steam supply part 19 Steam piping 20 Valve 23 Block off valve (valve)
24 Diffuser wall surface cooling device 25 1st cooling water supply device 26 1st cooling water piping 27 Spray cooling device 28 Cooling water nozzle 29 2nd cooling water supply device 30 2nd cooling water piping 32 2nd ejector injection nozzle 33 Bypass line 34 Bypass Valve 50 Outer pipe 52 Fuel gas flow path (target fluid flow path)
54 Steam channel (drive fluid channel)
56 tip 60 fuel gas 62 vapor 70 inner peripheral surface 72 outer peripheral surface 74 inner peripheral surface 80 convex portion 82 concave portion 84 inner diameter 86 outer diameter 88 central diameter 89 central axis 100 inner tube F flow direction

Claims (12)

A conduit having a curved cross section through which the target fluid flows in the first direction;
A nozzle that covers an outer periphery of the end portion in the first direction of the pipe line and is disposed on the outer periphery of the pipe line, and a driving fluid flows in the first direction;
The ejector according to claim 1, wherein the pipe has an uneven shape in which a radial position of an inner peripheral surface of the end portion changes in diameter according to a circumferential position.   2. The pipe according to claim 1, wherein the radial position of the inner peripheral surface of the end portion periodically changes along the circumferential direction, and a plurality of convex portions are formed in the circumferential direction. Ejector.   The said pipe line has the uneven | corrugated | grooved part by which the said uneven | corrugated shape was formed in the said edge part side, and the straight pipe part by which an internal peripheral surface becomes an ellipse or a circle in the said 1st direction upstream. Item 3. The ejector according to item 1 or 2.   4. The ejector according to claim 3, wherein the uneven portion includes a transition portion in which a distance between the uneven portion and the protruded portion becomes smaller toward the upstream side in the first direction.   In the conduit, the circumferential positions of the concave and convex concave portions and convex portions on the inner peripheral surface gradually change in one circumferential direction along the first direction, and the concave and convex portions are spiral. The ejector according to any one of claims 1 to 4, wherein the ejector is formed. The pipe has a circular cross section,
The ejector according to claim 1, wherein the nozzle has an annular shape.   The ejector according to any one of claims 1 to 6, wherein the pipe has an uneven shape in which a radial position of an outer peripheral surface of the end portion changes in diameter according to a circumferential position. .   8. The ejector according to claim 7, wherein a radial position of an outer peripheral surface of an end portion of the pipe line periodically changes in the same cycle as the inner peripheral surface along the circumferential direction. 9.   9. The nozzle according to claim 1, wherein the inner peripheral surface of the end portion on the downstream side in the first direction has a concave-convex shape in which a radial position changes in accordance with a circumferential position. The ejector according to claim 1.   The nozzle is characterized in that the radial position of the inner peripheral surface of the end portion on the downstream side in the first direction periodically changes in the same cycle as the inner peripheral surface of the pipe along the circumferential direction. The ejector according to claim 9.   A downstream pipe line that is connected to an end of the outer peripheral surface of the nozzle in the first direction and through which the target fluid and the driving fluid flow downstream of the nozzle and the pipe in the first direction. The ejector according to claim 1, wherein the ejector is characterized in that A high-air combustion test exhaust facility that houses a rocket engine and is connected to a low-pressure chamber into which combustion gas is injected, and into which the combustion gas flows,
A throat portion that is connected to the low-pressure chamber and guides along the flow direction of the combustion gas, and an expansion that is provided on the downstream side of the throat portion and that the flow passage cross-sectional area increases toward the downstream side in the flow direction of the combustion gas A diffuser having a portion,
The ejector according to any one of claims 1 to 11, wherein the ejector is installed in the throat portion and injects a driving fluid along the flow direction into the throat portion.
The ejector is a high-air combustion test exhaust system characterized in that the throat portion becomes a part of the pipe line, and the driving fluid is ejected from the nozzle to the throat portion.

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