Gas generating device based on wide-flow-range thermal spraying test and design method

Abstract

The invention relates to the technical field of thermal jet interference wind tunnel tests, in particular to a fuel gas generating device based on a wide flow range thermal jet test and a design method, the fuel gas generating device is integrated in a thermal jet interference wind tunnel test model, and comprises an injector, a combustion chamber and a spray pipe which are connected in sequence; the injector comprises a fuel injection core, an oxidizing agent injection cavity and a flow supplementing heat-proof flange, the oxidizing agent injection cavity is arranged around the fuel injection core, an ignition cavity is defined by the oxidizing agent injection cavity and the fuel injection core, and the flow supplementing heat-proof flange is arranged at the outlet end of the oxidizing agent injection cavity; the wall face of the oxidizing agent injection cavity is provided with an oxidizing agent injection hole communicated with the ignition cavity, and the wall face of the flow supplementing and heat preventing flange is provided with a flow supplementing and heat preventing injection hole communicated with the combustion chamber. According to the invention, the mixing rate and uniformity of the fuel and the oxidant are greatly improved, and the capability of a ground wide-flow-range thermal jet flow interference wind tunnel test is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hot-spray interference wind tunnel test, and particularly relates to a gas generating device based on wide-flow-range hot-spray test and a design method. BACKGROUND

[0002] Reaction control system (RCS) is a key technology for realizing high maneuvering orbit and attitude adjustment and control of a spacecraft through jet reaction force, and has been widely applied to various spacecrafts, including PAC-3 terminal interceptor missile, space shuttle, Shenzhou return capsule, lunar exploration return vehicle, HTV-2 hypersonic gliding vehicle, X-37B, THAAD high-altitude terminal interceptor missile and S-400 air defense system. RCS jet flow is derived from high-temperature gas generated by an engine, and the jet flow and the external flow of the spacecraft interact intensively, forming a flow structure containing complex shock wave structure and boundary layer interference separation, involving complex physical and chemical processes such as high-temperature effect, component transport and chemical non-equilibrium. The jet interference not only changes the external aerodynamic environment of the spacecraft, but also induces additional interference force and torque with strong nonlinear characteristics, which has a key influence on the stability and control of the spacecraft. Therefore, in the development process of various RCS spacecrafts, accurately predicting the jet interference force / torque and its nonlinear variation law has become one of the core problems of the overall and control design of the spacecraft.

[0003] In the past research on attitude control jet aircraft, ground wind tunnel test or numerical simulation usually uses normal temperature air to simulate high-temperature gas, and equivalent cold jet flow with the same pressure ratio and momentum ratio is used for hot jet flow. This method ignores the thermodynamic characteristics of high-temperature gas itself and the possible secondary combustion effect, but under the condition of small-flow jet, the interference force / torque data obtained basically meet the engineering precision requirements, and has been successfully applied to multiple types of tasks including Apollo spacecraft and Chinese Shenzhou return capsule.

[0004] However, for large-flow orbit control jet or large-flow reverse jet in the process of rocket recovery, the interference between the jet and the flow is more intense, and the "hot jet interference effect" caused by the component transport, thermal chemical non-equilibrium and other effects of high-temperature gas is highlighted, and the traditional cold jet simulation method has been difficult to meet the engineering precision requirements. With the development of future hypersonic aircraft towards faster, higher and more accurate, higher accuracy of RCS actual control force data is required, and hot jet simulation technology capable of reflecting the real gas characteristics, especially high-confidence hot jet wind tunnel test technology, is urgently needed.

[0005] At present, solid rocket engine or Ludwig tube is mainly used as high-temperature gas source in the domestic thermal spray interference test research. However, these methods are limited by test accuracy, gas composition control and operating parameter range, etc. The test results are mostly used for qualitative analysis. In addition, the existing thermal spray generation device based on methane / air has limited ignition capacity and narrow applicable flow range, which is difficult to cover the thermal spray test requirements under wide working conditions.

[0006] Therefore, developing a thermal spray flow generation method and device capable of realizing wide flow range and high control accuracy has become the key to improving the thermal spray interference test capability.

[0007] In view of this, the present application is proposed. SUMMARY

[0008] The purpose of the present application is to provide a gas generation device and design method based on wide flow range thermal spray test, which realizes the ground wide flow range thermal spray flow interference wind tunnel test capability.

[0009] In a first aspect, the present application provides a gas generation device based on wide flow range thermal spray test, which is integrated in the interior of a thermal spray flow interference wind tunnel test model, comprising a injector, a combustion chamber and a nozzle connected in sequence; The injector comprises a fuel injection core, an oxidizer injection cavity and a flow compensation heat protection flange, the oxidizer injection cavity is arranged around the fuel injection core, and the fuel injection core and the oxidizer injection cavity together define an ignition chamber, and the flow compensation heat protection flange is arranged at the outlet end of the oxidizer injection cavity. Wherein, a plurality of oxidizer injection holes are arranged on the wall surface of the oxidizer injection cavity and communicated with the ignition chamber, and a plurality of flow compensation heat protection injection holes are arranged on the wall surface of the flow compensation heat protection flange and communicated with the combustion chamber.

[0010] As a preferred embodiment of the present application, the fuel injection core is in L-shaped structure, which is composed of a horizontal section and a vertical section connected with each other, wherein the horizontal section is used for connecting the fuel supply pipeline, and the vertical section penetrates through the oxidizer injection cavity and extends into the ignition chamber, and a plurality of fuel injection holes are arranged on the side wall of the vertical section.

[0011] As a preferred embodiment of the present application, the oxidizer injection cavity is annular, and a plurality of oxidizer injection holes are arranged on the upstream and downstream of the fuel injection core along the circumferential direction of the oxidizer injection cavity.

[0012] As a preferred embodiment of the present application, the flow compensation heat protection flange is in flared conical structure, and the flow compensation heat protection injection holes are uniformly arranged along the circumferential direction of the flow compensation heat protection flange.

[0013] As the preferred technical solution, the combustion chamber is provided with a head flange near one end of the injector, and is provided with an igniter mounting hole, a thermocouple joint and a pressure sensor joint at the other end; The injector and the combustion chamber are detachably connected through the head flange and the flow compensation heat protection flange.

[0014] As the preferred technical solution, the igniter is threadedly connected with the oxidant injection cavity through an ignition cavity threaded hole opened at the top of the oxidant injection cavity, and / or the igniter is connected with the combustion chamber through an igniter mounting hole opened at the tail of the oxidant injection cavity.

[0015] As the preferred technical solution, a compression ring graphite gasket is arranged at the connecting flange between the injector and the combustion chamber and between the combustion chamber and the nozzle.

[0016] In the second aspect, the application also discloses a design method of the gas generating device based on the wide flow range hot injection test, which also belongs to the protection scope of the application, and specifically includes the following steps: Based on the internal space constraint of the wind tunnel test model, the overall layout design of the gas generating device is performed; Based on the pressure, temperature and thrust parameters of the target gas jet, the medium and flow parameters of the fuel and the oxidant are preliminarily determined through thermodynamic calculation; Based on the flow parameters and the sufficient mixing requirements of the fuel and the oxidant, the layout, number and area of the injection holes of the fuel injection core are designed; Based on the flow parameters and the cooling protection requirements of the fuel injection core, the layout, number and area of the injection holes of the oxidant injection cavity are designed; Based on the heat protection and flow compensation requirements, the structure form and flow compensation heat protection injection hole parameters of the flow compensation heat protection flange are designed; Based on the layout of the gas generating device and the ignition energy requirement, the selection of the igniter is completed; Each component is processed, and the fuel injection core, the oxidant injection cavity and the flow compensation heat protection flange are welded to form the injector; The injector, the combustion chamber and the nozzle are assembled into a sealed whole.

[0017] As the preferred technical solution, the final flow parameters of the fuel and the oxidant, the final injection hole parameters of the fuel injection core, and the final type of the igniter are verified and determined through the ground ignition test.

[0018] In the third aspect, the application also discloses an ignition control method of the gas generating device based on the wide flow range hot injection test, and the ignition timing of the ignition control method specifically includes the following steps: Starting the igniter; After the igniter is activated, fuel and oxidant are supplied to the gas generating unit in sequence; After confirming successful ignition, turn off the igniter; After the igniter is turned off, test data are collected; After data acquisition is complete, the supply of fuel and oxidizer is stopped, and the engine is shut down.

[0019] The present invention provides a gas generating device based on a wide flow range thermal spray test, which has at least the following beneficial effects: 1. The present invention relates to a gas generating device for wide-flow-range thermal spray testing, comprising an injector, a combustion chamber, and a nozzle connected in sequence. The injector includes a fuel injection core, an oxidizer injection chamber, and a flow-enhancing heat-resistant flange. The oxidizer injection chamber surrounds the fuel injection core and forms an ignition chamber. Multiple oxidizer nozzles communicating with the ignition chamber are formed on the wall of the oxidizer injection chamber. This increases the surface area of ​​the fuel jet, allowing the oxidizer to be injected from multiple angles and positions, breaking the symmetry of a single jet and generating numerous vortices. This significantly enhances the mixing rate and uniformity of the fuel and oxidizer, ensuring that the fuel does not extinguish due to poor mixing at low flow rates and that it does not experience severe oscillations or ablation due to improper local mixing ratios at high flow rates. This achieves the capability for wide-flow-range ground-based thermal spray interference wind tunnel testing. 2. The flow-injection heat-resistant flange of the gas generator based on the wide flow range thermal spray test of the present invention reduces the ignition flow in the ignition chamber and improves the ignition stability. By supplementing the flow through the flow-injection heat-resistant flange, the flow range that can achieve stable ignition is increased. 3. The present invention relates to a gas generator based on a wide flow range thermal spray test, wherein the make-up heat-proof flange has multiple make-up heat-proof nozzles connected to the combustion chamber. This allows a portion of the oxidant to not directly enter the main combustion zone, but instead be sprayed out along the inner wall of the combustion chamber through the make-up heat-proof nozzles. This portion of low-temperature oxidant forms a continuous, relatively low-temperature gas protective film between the hot wall and the high-temperature gas. On the one hand, this film can isolate the convective heat transfer from the high-temperature gas to the wall; on the other hand, as an oxidant, its own temperature is low before reaching the wall, allowing it to absorb heat from the wall. This significantly reduces the instantaneous heat load on the combustion chamber wall, enabling the device to withstand longer periods of high-temperature gas scouring, thus meeting the requirements of long-term wind tunnel testing. 4. This invention, based on a gas generation device for wide-flow-range thermal injection testing, can replicate the high temperature, specific components, and chemical non-equilibrium effects of real RCS engine gas at the principle level by controlling the type and mixing ratio of fuel and oxidizer injected into the fuel injection core and oxidizer injection chamber. Therefore, the jet generated by this device has a higher degree of matching with the jet under real flight conditions in key similarity parameters, fundamentally solving the bottleneck problem that cold injection simulation cannot reflect the interference effects of thermal injection, and providing more accurate data for overall and control design. Attached Figure Description

[0020] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0021] Figure 1 This is a design flowchart of the gas generating device based on a wide flow range thermal spray test according to the present invention; Figure 2 This is a schematic diagram of the gas generating device based on a wide flow range thermal spray test according to the present invention; Figure 3 This is a schematic diagram of the igniter in the gas generator based on the wide flow range thermal spray test of the present invention; Figure 4 This is a schematic diagram of the fuel injection core in the gas generator based on the wide flow range thermal spray test of the present invention; Figure 5 This is a schematic diagram of the oxidant injection chamber in the gas generator based on the wide flow range thermal spray test of the present invention; Figure 6 This is a schematic diagram of the flow-injection heat-resistant flange in the gas generator based on the wide flow range thermal spray test of the present invention. Figure 7 This is a schematic diagram of the combustion chamber in the gas generator based on the wide flow range thermal spray test of the present invention; Figure 8 This is a schematic diagram of the nozzle structure in the gas generating device based on the wide flow range thermal spray test of the present invention.

[0022] Figure label: 1: Ignition device; 2: Fuel injection core; 21: Fuel injection hole; 3: Oxidant injection chamber; 31: Fuel injection core connection hole; 32: Ignition chamber threaded hole; 33: Oxidizer injection hole; 4: Flow-replenishing heat-resistant flange; 41: Screw through hole; 42: Flow replenishment and heat protection nozzle; 43: Flared conical structure; 5: Combustion chamber; 51: Head flange; 52: Igniter mounting hole; 53: Thermocouple connector; 54: Pressure sensor connector; 6: Nozzle. Detailed Implementation

[0023] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0024] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application. As used herein, the singular form includes the plural form unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this description, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0025] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Example 1 like Figures 2-8 As shown, this embodiment provides a gas generating device based on a wide flow range thermal spray test. The gas generating device is integrated inside the thermal spray interference wind tunnel test model and includes an injector, a combustion chamber 5 and a nozzle 6 connected in sequence. In the injector, precise delivery, uniform mixing and stable ignition of fuel and oxidant can be achieved. In the combustion chamber 5, the uniformly mixed fuel and oxidant undergo a vigorous chemical reaction, converting chemical energy into thermal energy. Finally, the nozzle 6 converts the thermal energy into kinetic energy to generate a high-speed jet.

[0027] To address the shortcomings of previous thermal jet interference wind tunnel tests, such as insufficient ignition capability across a wide flow range, inability to control flow range, and inadequate heat protection of the combustion chamber 5, this embodiment employs an injector comprising a fuel injection core 2, an oxidizer injection chamber 3, and a flow-enhancing heat-resistant flange 4. The oxidizer injection chamber 3 surrounds the fuel injection core 2 and, together with the fuel injection core 2, defines an ignition chamber. Multiple oxidizer nozzles 33, communicating with the ignition chamber, are formed on the wall of the oxidizer injection chamber 3. This increases the surface area of ​​the fuel jet, allowing the oxidizer to be injected from multiple angles and positions, breaking the symmetry of a single jet and generating numerous vortices. This significantly enhances the mixing rate and uniformity of the fuel and oxidizer, ensuring that the fuel does not extinguish due to poor mixing at low flow rates and that it does not experience severe oscillations or ablation due to improper local mixing ratios at high flow rates. This achieves the capability for wide-flow-range thermal jet interference wind tunnel tests on the ground. The make-up flow heat-protection flange 4 is located at the outlet end of the oxidizer injection chamber 3, and multiple make-up flow heat-protection nozzles 42 communicating with the combustion chamber 5 are opened on the wall of the make-up flow heat-protection flange 4. This allows a portion of the oxidizer not to directly enter the main combustion zone, but to be sprayed out along the inner wall of the combustion chamber 5 through the make-up flow heat-protection nozzles 42. This portion of low-temperature oxidizer forms a continuous, relatively low-temperature gas protective film between the incandescent wall and the high-temperature combustion gas. On the one hand, it can isolate the convective heat transfer from the high-temperature combustion gas to the wall; on the other hand, as an oxidizer, its own temperature is low before reaching the wall, allowing it to absorb heat from the wall. This significantly reduces the instantaneous heat load on the wall of the combustion chamber 5, enabling the device to withstand the scouring of high-temperature combustion gas for a longer period of time, meeting the requirements of long-term wind tunnel testing.

[0028] Furthermore, the layout of the fuel injection core 2, oxidant injection chamber 3, and make-up heat-resistant flange 4 in this invention also utilizes a method of easy ignition with a small flow rate. After the small flow rate of fuel and oxidant is burned in the ignition chamber, the combustion gas then enters the combustion chamber 5 to ignite a large flow rate of oxidant and fuel, thereby significantly improving the ignition success rate.

[0029] In this embodiment, specifically, as Figure 4 As shown, the fuel injection core 2 has an L-shaped structure, consisting of interconnected horizontal and vertical sections. The horizontal section is used to connect to the fuel supply pipeline, and its head is equipped with a threaded connector to connect to the fuel gas source. The vertical section passes through the oxidizer injection chamber 3 and extends into the ignition chamber, and has multiple fuel injection holes 21 on its side wall. The arrangement of multiple fuel injection holes 21 allows the fuel to be injected from multiple angles and positions, further enhancing the mixing and uniformity of the fuel and oxidizer.

[0030] In this embodiment, specifically, as Figure 5 As shown, the oxidant injection chamber 3 is an annular injection chamber, and along the circumferential direction of the oxidant injection chamber 3, multiple oxidant injection holes 33 are provided on the oxidant injection chamber 3 at the upstream and downstream of the fuel injection core 2.

[0031] Oxidizer is injected simultaneously at multiple angles and locations upstream and downstream of the fuel injection core 2. The upstream injected oxidizer pre-cools and stabilizes the incoming fuel, thereby improving the heat resistance of the injection core. The downstream injected oxidizer directly participates in and intensifies the combustion process in the core area. This layout broadens the combustibility limit, allowing combustible conditions to still be formed locally when the overall mixture ratio deviates from the ideal value. This broadens the range of mixture ratios for stable operation and lays the foundation for achieving stable operation over a wide flow range.

[0032] In this embodiment, specifically, as Figure 6 As shown, the flow-injection heat-resistant flange 4 is a flared conical structure 43, while the flow-injection heat-resistant nozzles 42 are uniformly arranged along the circumferential direction of the flow-injection heat-resistant flange 4.

[0033] First, the circumferentially distributed replenishment and heat-prevention nozzles 42 ensure that the low-temperature oxidant can be uniformly sprayed into the combustion chamber 5 along the inner wall of the combustion chamber 5 without dead angles, forming a complete and continuous gas protective film on the inner wall surface of the combustion chamber 5. This significantly reduces the instantaneous heat load on the wall surface of the combustion chamber 5, allowing the device to withstand the scouring of high-temperature gas for a longer period of time. The flared conical structure 43 has a streamlined guiding effect, which can match the direction of the sprayed oxidant airflow with the expansion angle of the inner wall of the combustion chamber 5, thereby better "adhering" to the wall surface and greatly enhancing the stability and coverage effect of the gas film. Second, as the oxidant sprayed from the replenishment and heat-prevention nozzles 42 flows towards the nozzle 6, it will gradually mix with the high-temperature gas in the core area and participate in combustion, making the combustion process smoother and more controllable. Furthermore, if the combustion chamber 5 wall lacks effective thermal protection, its temperature will rise sharply. Conversely, if a thick wall is used for passive cooling, the wall temperature will be too low. This low temperature will alter the temperature and chemical reaction rate of the gas near the wall, distorting the temperature and component fields. Therefore, the inclusion of the flow-injection heat-resistant flange 4 and the flow-injection heat-resistant nozzle 42 in this invention not only significantly improves the durability and continuous operating time of the gas generator but also ensures the realism of the simulation and the validity of the experimental data.

[0034] In practical use, the flow rate of the oxidizer used for ignition in the ignition chamber and the supplementary flow rate of the oxidizer in the combustion chamber 5 can be adjusted by designing parameters such as the layout of the oxidizer nozzle 33 and the replenishment heat protection nozzle 42, the number of nozzles and the nozzle area.

[0035] It should be noted that, since the oxidizer injected into the make-up flow heat-resistant flange 4 is used to supplement the flow rate of the combustion chamber 5, thereby increasing the flow rate range of the hot jet test, and simultaneously purging the walls of the combustion chamber 5 to reduce their temperature, the make-up flow heat-resistant flange 4 can be designed to use either oxidizer injection from within the oxidizer injection chamber 3 or a separate gas line to supply oxidizer injection.

[0036] In this embodiment, specifically, as Figure 7 As shown, the combustion chamber 5 is provided with a head flange 51 at one end near the injector, and an igniter mounting hole 52, a thermocouple connector 53, and a pressure sensor connector 54 at the other end for installing the igniter 1, the thermocouple, and the pressure sensor. The injector and the combustion chamber 5 are detachably connected by screws through the head flange 51 and the flow-inducing heat-resistant flange 4, and are sealed by a compression annular graphite gasket.

[0037] Based on the above technical solution, and further preferably, the gas generating device based on the wide flow range thermal injection test in this embodiment also includes an igniter 1. The downstream of the igniter 1 has an external thread. The igniter 1 is threadedly connected to the oxidant injection chamber 3 through an ignition chamber threaded hole 32 opened at the top of the oxidant injection chamber 3, and / or the igniter 1 is connected to the combustion chamber 5 through an igniter 1 mounting hole 52 opened at the tail of the oxidant injection chamber 3. The method of igniting at the head of the injector and / or the tail of the combustion chamber 5 simultaneously improves the ignition success rate and stability, and broadens the range of flow rate and mixture ratio of the combustion chamber 5 for stable ignition. In practical applications, ignition can also be selected at the head of the injector or the tail of the combustion chamber 5, and the present invention does not strictly limit it.

[0038] Based on the above technical solution, more preferably, the injector and the combustion chamber 5 are detachably connected by screws through the head flange 51 and the flow-inducing heat-resistant flange 4, and the combustion chamber 5 and the nozzle 6 are detachably connected by screws. In order to further improve the sealing of the connection, a compression annular graphite gasket is provided at the flange of the connection.

[0039] Example 2 like Figure 1 As shown, this embodiment provides the most preferred design method for a gas generator based on a wide flow range thermal spray test, specifically including the following steps: Based on the internal space constraints of the wind tunnel test model, the overall layout design of the gas generating device is carried out. Specifically, based on the jet test conditions, the layout and internal space parameters of the test model, the thermal jet pressure, temperature, thrust and the geometric parameters of the nozzle 6 are determined, and the layout design of the gas generating device including components such as igniter 1, fuel injection core 2, oxidant injection chamber 3, make-up flow heat protection flange 4, combustion chamber 5 and nozzle 6 is completed. Based on the pressure, temperature, thrust, and nozzle geometry parameters of the gas jet required for the thermal jet interference wind tunnel, the medium and flow parameters of the fuel and oxidant required for the preliminary design test are calculated using thermodynamic software. Based on the flow parameters and the requirement for sufficient mixing of fuel and oxidant, the layout, number and area of ​​the nozzles of the fuel injection core 2 are designed. Specifically, based on the principles of stable ignition in the ignition chamber and thorough mixing of fuel and oxidant, the fuel injection core 2 is designed with parameters such as fuel injection hole layout, number of holes, and hole area, according to fuel flow parameters. Based on the flow parameters and the cooling protection requirements for the fuel injection core 2, the parameters such as the nozzle layout, number of nozzles, and nozzle area of ​​the oxidizer injection chamber 3 are designed. Based on the requirements of heat protection and flow replenishment, the structural form of the flow replenishment heat protection flange 4 and the layout, number of nozzles, and area of ​​the flow replenishment heat protection nozzles 42 are designed. Based on the layout of the gas generator and the ignition energy requirements, the selection and layout design of igniter 1 were completed. Specifically, the igniter type 1 is a small-sized high-energy igniter 1, and the final model is determined based on the ignition test of the gas generating device; Based on the layout design parameters of the gas generator and the design parameters of the make-up flow heat protection flange 4, the parameter and structural design of the combustion chamber 5 and the nozzle 6 were completed. Based on the above design parameters, the processing of each component was completed, and the fuel injection core 2, oxidant injection chamber 3 and replenishment heat protection flange 4 were welded together to form an injector; The press-fit sealing ring threaded connection method assembles the injector, combustion chamber 5 and nozzle 6 into a sealed whole.

[0040] Among them, the final flow parameters of fuel and oxidant, the nozzle layout, number of nozzles, nozzle area and other final nozzle parameters of fuel injection core 2, as well as the final model of igniter 1, are all verified and determined through ground ignition tests. The combustion chamber 5 can be designed with different layouts based on test requirements such as lateral jet flow and reverse jet flow.

[0041] Finally, the gas generator obtained by assembling and matching the igniter 1, fuel injection core 2, oxidant injection chamber 3, make-up flow heat protection flange 4, combustion chamber 5 and nozzle 6 is identical in shape to the original digital model.

[0042] Example 3 This embodiment discloses the ignition control method for the gas generator based on the above-mentioned wide flow range thermal spray test, including the following steps: S1. Integrate and install the device inside the wind tunnel test model, and connect the fuel and oxidizer supply pipelines as well as the circuits of the ignition and data acquisition system; S2. Start igniter 1 to establish an initial high-energy ignition source at the head of combustion chamber 5, creating stable ignition conditions for the subsequent introduction of combustibles. S3. After confirming that the ignition source is stable, open the fuel and oxidizer supply valves in sequence according to the predetermined time. The sequence of "fuel first, then oxidizer" or "ignition first, then gas supply" is crucial here. It can avoid the formation of uncontrollable premixed combustible gas masses in the combustion chamber 5, ensure a smooth and controllable ignition process, and eliminate the risk of deflagration. S4. After confirming successful ignition, immediately turn off igniter 1. This eliminates electromagnetic interference from igniter 1 to the high-precision measuring sensor and protects igniter 1 itself. Subsequently, during the stable generation of high-temperature gas jets by the device, various data (such as aerodynamic forces, pressure, temperature field, etc.) of wind tunnel inflow and jet interference are collected simultaneously. S5. After completing the data acquisition for the predetermined duration, simultaneously cut off the supply of fuel and oxidizer to quickly shut down the device and end the test.

[0043] The ignition timing designed in this invention can improve the ignition success rate. After successful ignition, turning off the igniter 1 can avoid interference from the igniter 1 with measurement signals such as pressure and temperature, and at the same time extend the service life of the igniter 1.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A gas generating device based on a wide flow range thermal spray test, characterized in that, The gas generating device is integrated inside the thermal jet interference wind tunnel test model, including an injector, a combustion chamber and a nozzle connected in sequence; The injector includes a fuel injection core, an oxidizer injection chamber, and a make-up flow heat protection flange. The oxidizer injection chamber is arranged around the fuel injection core and together with the fuel injection core, defines an ignition chamber. The make-up flow heat protection flange is located at the outlet end of the oxidizer injection chamber. Preferably, the oxidizer injection chamber has multiple oxidizer injection holes communicating with the ignition chamber on its wall surface, and the make-up flow heat-proof flange has multiple make-up flow heat-proof injection holes communicating with the combustion chamber on its wall surface.

2. The gas generating device based on a wide flow range thermal spray test according to claim 1, characterized in that, The fuel injection core has an L-shaped structure, consisting of interconnected horizontal and vertical sections; wherein, the horizontal section is used to connect the fuel supply pipeline, the vertical section passes through the oxidizer injection chamber and extends into the ignition chamber, and multiple fuel injection holes are provided on the side wall.

3. The gas generating device based on a wide flow range thermal spray test according to claim 1, characterized in that, The oxidant injection chamber is an annular injection chamber; Preferably, along the circumferential direction of the oxidant injection cavity, multiple oxidant injection holes are provided on the oxidant injection cavity both upstream and downstream of the fuel injection core.

4. The gas generating device based on a wide flow range thermal spray test according to claim 1, characterized in that, The heat-resistant flow-injection flange has a flared conical structure; Preferably, the flow replenishment and heat protection nozzles are evenly arranged along the circumferential direction of the flow replenishment and heat protection flange.

5. The gas generating device based on a wide flow range thermal spray test according to claim 1, characterized in that, The combustion chamber is provided with a head flange at one end near the injector, and an igniter mounting hole, a thermocouple connector, and a pressure sensor connector at the other end. Preferably, the injector and the combustion chamber are detachably connected via the head flange and the make-up flow heat-resistant flange.

6. The gas generating device based on a wide flow range thermal spray test according to claim 1, characterized in that, It also includes an igniter, which is threadedly connected to the oxidizer injection chamber through an ignition chamber threaded hole at the top of the oxidizer injection chamber, and / or the igniter is connected to the combustion chamber through an igniter mounting hole at the tail of the oxidizer injection chamber.

7. The gas generating device based on a wide flow range thermal spray test according to claim 1, characterized in that, A compression annular graphite gasket is provided at the connecting flange between the injector and the combustion chamber, and between the combustion chamber and the nozzle.

8. A design method for a gas generating device based on a wide flow range thermal spray test as described in any one of claims 1-7, characterized in that, Includes the following steps: Based on the internal space constraints of the wind tunnel test model, the overall layout design of the gas generating device is carried out. Based on the pressure, temperature, and thrust parameters of the target gas jet, the medium and flow parameters of the fuel and oxidizer are preliminarily determined through thermodynamic calculations. Based on the flow parameters and the requirement for sufficient mixing of fuel and oxidant, the layout, number and area of ​​the nozzles of the fuel injection core are designed. Based on the flow parameters and the cooling and protection requirements for the fuel injection core, the layout, number, and area of ​​the nozzles in the oxidizer injection chamber are designed. Based on the requirements of heat protection and flow replenishment, the structural form of the flow replenishment heat protection flange and the parameters of the flow replenishment heat protection nozzle are designed. Based on the layout of the gas generator and the ignition energy requirements, the igniter selection was completed; Process the various components and weld the fuel injection core, oxidizer injection chamber and make-up heat-resistant flange together to form an injector; The injector, combustion chamber, and nozzle are assembled into a sealed unit.

9. The design method of a gas generator based on a wide flow range thermal spray test according to claim 8, characterized in that, The final flow parameters of the fuel and the oxidant, the final nozzle parameters of the fuel injection core, and the final model of the igniter were all verified and determined through ground ignition tests.

10. An ignition control method for a gas generator based on a wide flow range thermal spray test as described in any one of claims 1-7, characterized in that, The ignition timing sequence includes the following steps: Start the ignition; After the igniter is activated, fuel and oxidant are supplied to the gas generating unit in sequence; After confirming successful ignition, turn off the igniter; After the igniter is turned off, test data are collected; After data acquisition is complete, the supply of fuel and oxidizer is stopped, and the engine is shut down.

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