Control device for flow separation of engine jet pipe

Abstract

The utility model relates to the field of rocket engines, in particular to a control device for flow separation of an engine jet pipe, which comprises a turbine exhaust pipe and exhaust nozzles, one end of the turbine exhaust pipe is used for being communicated with an exhaust end of a turbine, and the other end of the turbine exhaust pipe is respectively communicated with inlets of a plurality of exhaust nozzles. The multiple exhaust nozzles are arranged in the circumferential direction of the outlet end of the engine jet pipe at intervals, and outlets of the exhaust nozzles face the exhaust direction of the engine jet pipe. Turbine exhaust is introduced to the position close to an outlet of the spray pipe to be sprayed out of the engine spray pipe, supersonic jet flow is formed, atmosphere backflow is hindered, flow separation of the spray pipe is restrained, turbine exhaust is further accelerated, and the dual purposes of avoiding flow separation of the large-area-ratio spray pipe and improving the specific impulse of turbine exhaust are achieved. The nozzle divergence ratio and the engine specific impulse can be improved, and the engine performance is improved. A control gas source adopts turbine exhaust, the utilization rate of waste gas is improved, and the device has the advantages of simple structure, high performance, strong applicability and the like.

Description

Technical Field

[0001] The utility model relates to the field of rocket engines, in particular to a control device for engine nozzle flow separation. Background Art

[0002] The nozzle generates most of the thrust of the rocket engine. The larger the nozzle area ratio, the higher the engine performance and the greater the rocket's carrying capacity. However, for traditional bell-shaped nozzles with large area ratios, the outlet pressure is low, which is prone to flow separation in low-altitude flight. The separation is often asymmetric, which brings harmful side loads to the nozzle and engine. In addition, after the nozzle gas passes through the separation shock wave, the static temperature rises suddenly, which can easily cause nozzle wall ablation and endanger the engine structure.

[0003] In engineering, limiting the nozzle area ratio is often used to increase the nozzle outlet wall pressure to avoid flow separation, but this also restricts the improvement of engine performance. There are other measures to suppress flow separation in large area ratio nozzles, but most of these measures are very complex and difficult to apply in engineering.

[0004] A major feature of nozzle flow separation is that the atmosphere flows upward along the inner wall of the nozzle, causing the nozzle gas to separate from the nozzle wall. If the backflow of the atmosphere can be prevented, the nozzle flow separation can be eliminated, thereby increasing the nozzle area ratio without separation, thereby improving engine performance. Utility Model Content

[0005] The technical problem to be solved by the utility model is how to eliminate the flow separation of the nozzle.

[0006] The utility model provides a technical solution to the above-mentioned technical problem as follows: a control device for engine nozzle flow separation, comprising a turbine exhaust pipe and an exhaust nozzle, one end of the turbine exhaust pipe being used to communicate with the exhaust end of the turbine, the other end of the turbine exhaust pipe being respectively connected with the inlets of a plurality of the exhaust nozzles, the plurality of exhaust nozzles being arranged at circumferential intervals along the outlet end of the engine nozzle, and the outlets of the exhaust nozzles being oriented toward the exhaust direction of the engine nozzle.

[0007] The beneficial effects of the utility model are: the turbine exhaust is introduced near the nozzle outlet and ejected into the engine nozzle to form a supersonic jet, which hinders atmospheric backflow and inhibits nozzle flow separation. The turbine exhaust can also be further accelerated, achieving the dual purpose of avoiding large-area nozzle flow separation and improving turbine exhaust specific impulse, which can improve the nozzle expansion ratio and engine specific impulse and improve engine performance. The control gas source uses turbine exhaust, which improves the utilization rate of exhaust gas and has the advantages of simple structure, high performance and strong applicability.

[0008] On the basis of the above technical solution, the present invention can also be improved as follows.

[0009] Optionally, the turbine exhaust pipe is a metal rigid pipe.

[0010] The beneficial effect of adopting the above optional solution is that if the engine is a pump-front swing engine, the turbine exhaust pipe can be a metal hard pipe.

[0011] Optionally, the turbine exhaust pipe is a metal hose.

[0012] The beneficial effect of adopting the above optional solution is that if the engine is a pump-back engine, the turbine exhaust pipe must be a metal hose.

[0013] Furthermore, it also includes an air collecting ring, which is an annular pipe. The air collecting ring is fixedly sleeved on the outlet end of the engine nozzle, and the other end of the turbine exhaust pipe is connected and communicated with the air collecting ring. A plurality of exhaust nozzles are arranged at intervals along the circumference of the air collecting ring, and the inlet of the exhaust nozzle is connected and communicated with the air collecting ring.

[0014] The beneficial effect of adopting the above further scheme is that the air collecting ring evenly guides the exhaust gas of the turbine exhaust pipe to the circumference of the engine nozzle, and evenly supplies air to multiple exhaust nozzles, with good jet uniformity.

[0015] Furthermore, there are multiple turbine exhaust pipes.

[0016] The beneficial effect of adopting the above further solution is that: a plurality of turbine exhaust pipes can be provided, and air can be supplied to multiple positions of the air collecting ring at the same time, and the air supply is uniform.

[0017] Furthermore, the edge of the air collecting ring away from the turbine exhaust pipe is flush with the end surface of the outlet end of the engine nozzle.

[0018] Furthermore, the exhaust nozzle is a convergent-divergent nozzle.

[0019] The beneficial effect of adopting the above further solution is that the convergent-divergent nozzle can accelerate the turbine exhaust to supersonic speed and hinder the atmospheric backflow.

[0020] Furthermore, the cross-sectional shape of the exhaust nozzle is rectangular or circular.

[0021] Furthermore, the area ratio of the expansion section of the convergence-divergence nozzle is 1-3.

[0022] The beneficial effect of adopting the above further solution is that by adopting this area ratio, the energy of the turbine exhaust gas can be better converted into specific impulse.

[0023] Furthermore, the angle between the axial direction of the exhaust nozzle and the axial direction of the engine nozzle is greater than or equal to 0° and less than or equal to 15°.

[0024] The beneficial effect of adopting the above further solution is that if the angle of the exhaust nozzle exceeds the angle range of 0-15°, it may interfere with the mainstream of the engine nozzle and weaken the device's ability to suppress separation. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a structural schematic diagram of a control device for engine nozzle flow separation according to the utility model;

[0026] Figure 2 This is a schematic structural diagram of a turbine exhaust pipe of a control device for flow separation of an engine nozzle according to the utility model, which is a metal hose;

[0027] Figure 3 It is the contour line diagram of the flow field Mach number of the existing open cycle engine nozzle without the flow separation control device;

[0028] Figure 4 It is a flow field Mach number contour diagram of a control device for engine nozzle flow separation of the utility model;

[0029] Figure 5 This is a partial enlarged view of the exhaust nozzle.

[0030] In the accompanying drawings, the components represented by the reference numerals are listed as follows:

[0031] 1. Turbine exhaust pipe, 2. Collecting ring, 3. Exhaust nozzle, 4. Turbine; 5. Engine nozzle. DETAILED DESCRIPTION

[0032] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0033] like Figure 1-Figure 5 As shown, this embodiment provides a control device for engine nozzle flow separation, including a turbine exhaust pipe 1 and an exhaust nozzle 3, wherein one end of the turbine exhaust pipe 1 is used to communicate with the exhaust end of the turbine 4, and the other end of the turbine exhaust pipe 1 is respectively connected to the inlets of multiple exhaust nozzles 3, and the multiple exhaust nozzles 3 are arranged at intervals along the circumference of the outlet end of the engine nozzle 5, and the outlets of the exhaust nozzles 3 are oriented toward the exhaust direction of the engine nozzle 5.

[0034] The turbine exhaust is introduced near the nozzle outlet and ejected into the engine nozzle 5 to form a supersonic jet, which hinders atmospheric backflow, inhibits nozzle flow separation, and can further accelerate the turbine exhaust, achieving the dual purpose of avoiding large-area nozzle flow separation and improving turbine exhaust specific impulse, which can improve the nozzle expansion ratio and engine specific impulse, and improve engine performance. The control gas source uses turbine exhaust, which improves the utilization rate of exhaust gas and has the advantages of simple structure, high performance and strong applicability.

[0035] The control device for engine nozzle flow separation of this embodiment is particularly suitable for open cycle engines, and can also be used for other engines with an engine nozzle 5.

[0036] In one specific example, the plurality of exhaust nozzles 3 are evenly distributed along the circumference of the outlet end of the engine nozzle 5 .

[0037] The outlet of the exhaust nozzle 3 faces the exhaust direction of the engine nozzle 5, which means that the direction of the gas discharged from the outlet of the exhaust nozzle 3 is exactly the same as the direction of the gas discharged from the engine nozzle 5 or the angle between them is an acute angle.

[0038] Among them, the outlet end of the exhaust nozzle 3 passes through the side wall of the engine nozzle 5 and is located inside the engine nozzle 5; or the exhaust nozzle 3 is installed at the end of the engine nozzle 5, and the outlet end of the exhaust nozzle 3 is tilted toward the axial direction of the engine nozzle 5, and there is no need to open a through hole in the side wall of the engine nozzle 5 for the exhaust nozzle 3 to pass through.

[0039] Optional, such as Figure 1 As shown, the turbine exhaust pipe 1 is a metal hard pipe.

[0040] Specifically, if the engine is a pump-front swing engine, the turbine exhaust pipe 1 may be a metal hard pipe.

[0041] Optional, such as Figure 2 As shown, the turbine exhaust pipe 1 is a metal hose.

[0042] Specifically, if the engine is a pump-back engine, the turbine exhaust pipe 1 must be a metal hose.

[0043] On the basis of the above technical solution, the other end of the turbine exhaust pipe 1 is respectively connected to the inlets of the plurality of exhaust nozzles 3, and has the following implementation modes:

[0044] Embodiment 1: The control device for engine nozzle flow separation also includes an air collecting ring 2, which is an annular pipe. The air collecting ring 2 is fixedly sleeved on the outlet end of the engine nozzle 5, and the other end of the turbine exhaust pipe 1 is connected and communicated with the air collecting ring 2. A plurality of exhaust nozzles 3 are arranged at intervals along the circumference of the air collecting ring 2, and the inlet of the exhaust nozzle 3 is connected and communicated with the air collecting ring 2.

[0045] The air collecting ring 2 guides the exhaust gas from the turbine exhaust pipe 1 evenly to the circumference of the engine nozzle 5, and evenly supplies air to the multiple exhaust nozzles 3, so that the jet uniformity is good.

[0046] Optionally, the cross-section of the air collecting ring 2 (annular pipe) perpendicular to its length direction is circular, semicircular, elliptical or rectangular, that is, the air collecting ring 2 also forms a complete pipeline structure when it is not assembled with the engine nozzle 5; or, the cross-section of the air collecting ring 2 perpendicular to its length direction is an arc-shaped plate, and after the air collecting ring 2 is fixedly connected to the outer wall of the engine nozzle 5, an annular cavity for gas to pass through is formed between the air collecting ring 2 and the side wall of the engine nozzle 5.

[0047] Furthermore, there are multiple turbine exhaust pipes 1 , and the other ends of the multiple turbine exhaust pipes 1 are connected and communicated with the gas collecting ring 2 .

[0048] The turbine exhaust pipe 1 can be provided in multiple numbers to supply air to multiple positions of the air collecting ring 2 at the same time, and the air supply is uniform.

[0049] Furthermore, the edge of the gas collecting ring 2 away from the turbine exhaust pipe 1 is flush with the end surface of the outlet end of the engine nozzle 5 .

[0050] Embodiment 2: There are multiple turbine exhaust pipes 1, and the multiple turbine exhaust pipes 1 are connected and communicated with the multiple exhaust nozzles 3 in a one-to-one correspondence.

[0051] Based on any of the above embodiments, the exhaust nozzle 3 is a convergent-divergent nozzle.

[0052] Among them, the convergent-divergent nozzle is also called a Laval nozzle or a supersonic nozzle. The convergent-divergent nozzle can accelerate the turbine exhaust to supersonic speed and hinder the atmospheric backflow.

[0053] Based on any of the above embodiments, the cross-sectional shape of the exhaust nozzle 3 is rectangular or circular.

[0054] The cross-sectional shape of the exhaust nozzle 3 refers to the shape of the cross section perpendicular to the jetting direction.

[0055] Based on any of the above implementations, the area ratio of the expansion section of the convergent-divergent nozzle is 1-3.

[0056] By adopting this area ratio, the energy of turbine exhaust gas can be better converted into specific impulse.

[0057] Specifically, the convergent-divergent nozzle includes an inlet cone, a throat and an expansion section connected in sequence, and the expansion section area ratio refers to the area ratio of the expansion section outlet to the throat.

[0058] Based on any of the above embodiments, the angle between the axial direction of the exhaust nozzle 3 and the axial direction of the engine nozzle 5 is greater than or equal to 0° and less than or equal to 15°.

[0059] If the angle of the exhaust nozzle exceeds the 0-15° angle range, it may interfere with the engine nozzle mainstream and weaken the device's ability to suppress separation.

[0060] Figure 3 and Figure 4 They are the Mach number contour diagrams of the flow field of the open cycle engine nozzle under sea level conditions, with and without the engine nozzle flow separation control device. It can be seen from the figure that Figure 3 and Figure 4 The flow field at the middle arrow point changes significantly. The control device for engine nozzle flow separation proposed in the utility model can avoid the flow separation phenomenon that occurs in a large area of ​​the nozzle under sea level conditions, indicating that the solution disclosed in the utility model is practicable.

[0061] In the description of the present invention, it should be noted that the terms "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0062] In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0063] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0064] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0065] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0066] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A control device for engine nozzle flow separation, characterized in that: The invention comprises a turbine exhaust pipe (1) and an exhaust nozzle (3), wherein one end of the turbine exhaust pipe (1) is used to communicate with the exhaust end of a turbine (4), and the other end of the turbine exhaust pipe (1) is respectively communicated with the inlets of a plurality of exhaust nozzles (3), wherein the plurality of exhaust nozzles (3) are arranged at intervals along the circumference of the outlet end of an engine nozzle (5), and the outlets of the exhaust nozzles (3) face the exhaust direction of the engine nozzle (5).

2. The control device for engine nozzle flow separation according to claim 1, characterized in that: The turbine exhaust pipe (1) is a metal hard pipe.

3. The control device for engine nozzle flow separation according to claim 1, characterized in that: The turbine exhaust pipe (1) is a metal hose.

4. The control device for engine nozzle flow separation according to claim 1, characterized in that: It also includes an air collecting ring (2), which is an annular pipe. The air collecting ring (2) is fixedly sleeved on the outlet end of the engine nozzle (5), and the other end of the turbine exhaust pipe (1) is connected to and communicated with the air collecting ring (2). A plurality of exhaust nozzles (3) are arranged at intervals along the circumference of the air collecting ring (2), and the inlet of the exhaust nozzle (3) is connected to and communicated with the air collecting ring (2).

5. The control device for engine nozzle flow separation according to claim 4, characterized in that: The turbine exhaust pipe (1) is multiple.

6. The control device for engine nozzle flow separation according to claim 4, characterized in that: The edge of the gas collecting ring (2) at one end away from the turbine exhaust pipe (1) is flush with the end surface of the outlet end of the engine nozzle (5).

7. The control device for engine nozzle flow separation according to claim 1, characterized in that: The exhaust nozzle (3) is a convergent-divergent nozzle.

8. The control device for engine nozzle flow separation according to claim 7, characterized in that: The cross-sectional shape of the exhaust nozzle (3) is rectangular or circular.

9. The control device for engine nozzle flow separation according to claim 7, characterized in that: The area ratio of the expansion section of the convergence-divergence nozzle is 1-3.

10. The control device for engine nozzle flow separation according to any one of claims 1 to 9, characterized in that: The included angle between the axial direction of the exhaust nozzle (3) and the axial direction of the engine nozzle (5) is greater than or equal to 0° and less than or equal to 15°.

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