A thermal shock test method and test device for evaluating flame tube life parameters

Abstract

The application belongs to the technical field of aero-engines. A thermal shock test method and test device for evaluating flame tube life parameters are disclosed. The test object in the method is a flame tube. Compared with whole machine level life examination, only the requirements and conditions of the flame tube test need to be considered, the requirements and conditions of components unrelated to the flame tube can be reduced, and the test operation is simplified. The failure mechanism (intergranular fracture or transgranular fracture) of the flame tube and the thermal shock cycle spectrum (triangular cycle or rectangular cycle) are determined by using the working condition, so that the flame tube life test acceleration processing can be realized. By flexibly adjusting the temperature of the main road gas and the impact gas, different gas environments can be simulated, the flame tube wall temperature of different working conditions can be achieved, the investigation of the alternating stress of the flame tube under high temperature creep and low cycle can be realized, and a method for considering the actual working gas environment and evaluating the flame tube life at the component level is provided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of aero-engines, in particular to a thermal shock test method and test device for evaluating flame tube life parameters. BACKGROUND

[0002] With the continuous development of aviation technology, the outlet temperature and temperature rise of the combustion chamber are higher and higher, and the working environment of the flame tube is also more and more severe. Since the flame tube works in a high-temperature and high-pressure environment, the material of the flame tube will produce creep deformation under the action of high temperature; there is a large temperature gradient on the wall surface of the flame tube, which will also produce a large thermal stress; the flame tube also needs to withstand alternating thermal stress when the engine works in different states; the flame tube gas surface will also be oxidized in the gas environment. Serious deformation, cracks, ablation, and severe oxidation and other failures will directly affect the service life and flight safety of the aero-engine, so it is necessary to carry out life research on the flame tube.

[0003] In the life prediction of hot end components, factors such as low cycle fatigue, high temperature creep and creep-fatigue interaction are mainly considered. At present, the following three methods are mainly used for flame tube life evaluation: 1) long-term ground test with engine, through the specified test cycle spectrum, the engine is tested for life, and the flame tube life is evaluated through inspection; 2) numerical calculation, under selected working conditions, based on the classical elastic-plastic constitutive theory, the stress method recommended by the British stress standard (ESD-3, stress standard for MK202 engine) is used to check the strength of the flame tube; 3) same material test piece test. Select the test piece of the same material as the flame tube, heat it through the temperature cycle spectrum, and observe the cycle number of crack occurrence.

[0004] However, when using the long-term ground test with engine method, the working object is the engine, which requires more test requirements and conditions, making the test operation more complex; when using the numerical calculation method, it is generally necessary to select the most severe working condition for strength checking on the project, which will make the calculation condition single, and the alternating stress change when the flame tube switches between different states is not considered, so the correctness of the test result needs to be verified; when using the same material test piece test method, the flame tube profile structure needs to be simplified into a test piece, which focuses on the mechanism of material damage, and does not reproduce the structure characteristics of the flame tube and the actual working gas environment. In short, the current flame tube life evaluation method is complex or does not consider the actual flame tube structure, gas working environment, and alternating stress change when switching between different working states, lacks consideration of the actual working gas environment, and there is no method for flame tube life evaluation at the component level. SUMMARY

[0005] Therefore, the technical problem to be solved by the present application is to provide a method for evaluating the service life of a flame tube at the component level and considering the actual working gas environment, due to the current service life evaluation method of the flame tube in the prior art, which is complicated to operate or does not consider the actual structure of the flame tube, the working gas environment, and the alternating stress changes during switching between different working states.

[0006] To this end, the present application provides a thermal shock test method for evaluating the service life parameters of a flame tube, comprising:

[0007] Step S1: pass the main gas into the flame tube to uniformly heat the flame tube body, and pass the impact gas to impact the preset area of the flame tube to increase the local temperature of the preset area;

[0008] Step S2: record the temperature value of the preset area;

[0009] Step S3: control the temperature of the main gas and the impact gas to raise the flame tube from an A working condition temperature to a B working condition temperature, and then lower the flame tube from the B working condition temperature to the A working condition temperature;

[0010] Step S4: repeat the step S3 until cracks of a preset size appear on the outer wall of the flame tube, record the number of repetitions of the step S3, and obtain the service life parameters of the flame tube.

[0011] Optionally, the thermal shock test method for evaluating the service life parameters of the flame tube, the step S2 comprises:

[0012] Step S21: weld a thermocouple in the preset area;

[0013] Step S22: electrically connect the thermocouple with a temperature measuring element to monitor the temperature of the thermocouple through the temperature measuring element.

[0014] Optionally, the thermal shock test method for evaluating the service life parameters of the flame tube, the step S21 specifically comprises:

[0015] Step S211: take any hot spot in the preset area as the center and weld a thermocouple;

[0016] Step S212: make circular arcs with R1, R2,..., RN as the radii, and weld thermocouples at all four quarters of the circular arcs.

[0017] Optionally, the thermal shock test method for evaluating the service life parameters of the flame tube,

[0018] In the step S3, the flame tube is heated to the B working condition temperature, and a hold should also be performed, and the holding time is t.

[0019] Optionally, the thermal shock test method for evaluating the service life parameters of the flame tube,

[0020] In the step S4, the preset size of the crack of the outer wall of the flame tube used should be less than or equal to 1 mm.

[0021] A thermal shock test device for evaluating the service life parameters of a flame tube, used for the thermal shock test method for evaluating the service life parameters of a flame tube, the thermal shock test device comprises:

[0022] A chamber adapted to accommodate a flame tube sample;

[0023] A main combustion chamber, a flame outlet of the main combustion chamber passing through the chamber through a first pipeline and extending to the inside of the flame tube;

[0024] A shock combustion chamber, a flame outlet of the shock combustion chamber passing through the chamber through a second pipeline and extending to a preset region of the outer wall of the flame tube.

[0025] Optionally, the thermal shock test device for evaluating the service life parameters of a flame tube,

[0026] The inside of the chamber is in communication with an external cold gas source through a third pipeline.

[0027] Optionally, the thermal shock test device for evaluating the service life parameters of a flame tube,

[0028] A thermocouple is welded in the preset region;

[0029] Further comprising a temperature measuring element, an electrical connection end of the temperature measuring element being electrically connected to an electrical connection end of the thermocouple, the temperature measuring element being used for receiving a thermoelectric electromotive force signal transmitted by the thermocouple and converting the thermoelectric electromotive force signal into a temperature.

[0030] Optionally, the thermal shock test device for evaluating the service life parameters of a flame tube,

[0031] Further comprising a control element, an electrical connection end of the control element being connected to an electrical connection end of a switch element used for controlling the on-off of the flame outlet of the main combustion chamber through a wire, and an electrical connection end of the control element being connected to an electrical connection end of a switch element used for controlling the on-off of the flame outlet of the shock combustion chamber through a wire.

[0032] Optionally, the thermal shock test device for evaluating the service life parameters of a flame tube,

[0033] Further comprising a feedback mechanism, the feedback mechanism being used for feeding back the degree of gas shock provided by the main combustion chamber or the shock combustion chamber according to the wall temperature of the flame tube.

[0034] The technical solution provided by the present application has the following advantages:

[0035] The thermal shock test method for evaluating the service life parameters of a flame tube provided by the present application comprises:

[0036] Step S1: the main gas is introduced into the flame tube to uniformly heat the flame tube body, and the impact gas is used to impact the preset area of the flame tube to increase the local temperature of the preset area;

[0037] Step S2: record the temperature value of the preset area;

[0038] Step S3: control the temperature of the main gas and the impact gas to make the flame tube rise from the A working condition temperature to the B working condition temperature, and then drop from the B working condition temperature to the A working condition temperature;

[0039] Step S4: repeat the step S3 until a crack of a preset size appears on the outer wall of the flame tube, record the number of repetitions of the step S3 and obtain the service life parameter of the flame tube.

[0040] The thermal shock test method for evaluating the service life parameter of the flame tube used in the present application can realize uniform heating of the flame tube body by using the main gas to flow into the inside of the flame tube, and can simulate the flame tube wall temperature gradient under the specified state by using the impact gas to heat the preset area arranged on the flame tube. Since the test object in the existing scheme is the engine as a whole, which includes the flame tube and the components outside the flame tube, and the test object in the present method is only the flame tube required for testing, only the requirements and conditions of the flame tube during testing are considered, the requirements and conditions of the components unrelated to the flame tube are reduced, and the test operation is simplified. By using the working condition to determine the failure mechanism (intergranular fracture or transgranular fracture) and the thermal shock cycle spectrum (triangular cycle or rectangular cycle), the service life test of the flame tube can be accelerated. By flexibly adjusting the temperature of the main gas and the impact gas, different gas environments can be simulated, the flame tube wall temperature under different working conditions can be achieved, the investigation of the alternating stress of the flame tube under high temperature creep and low cycle can be realized, and a method of considering the actual working gas environment and evaluating the service life of the flame tube at the component level is provided. The test object used in the test method is the flame tube, compared with the whole machine level life test, only the requirements and conditions of the flame tube during testing are considered, the requirements and conditions of the components unrelated to the flame tube are reduced, and the test operation is simplified. A method of considering the actual working gas environment and evaluating the service life of the flame tube at the component level is provided. BRIEF DESCRIPTION OF DRAWINGS

[0041] In order to more clearly illustrate the specific embodiments of the present application or the technical solutions in the prior art, the drawings needed in the following specific embodiments or prior art description will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0042] Figure 1 Flow chart of the thermal shock test method for evaluating the service life parameters of the flame tube in the present application;

[0043] Figure 2 Flow chart of step S2 in the thermal shock test method for evaluating the service life parameters of the flame tube in the present application;

[0044] Figure 3 Flow chart of step S21 in the thermal shock test method for evaluating the service life parameters of the flame tube in the present application;

[0045] Figure 4 Structural schematic diagram of the thermal shock test device for evaluating the service life parameters of the flame tube in the present application;

[0046] Figure 5 Thermocouple distribution schematic diagram when the number of thermocouples in the thermal shock test device for evaluating the service life parameters of the flame tube in the present application is five;

[0047] Figure 6 Cycle spectrum diagram used by the thermal shock test device for evaluating the service life parameters of the flame tube in the present application;

[0048] Explanation of reference signs:

[0049] 1-flame tube;

[0050] 2-casing;

[0051] 3-main combustion chamber;

[0052] 4-impingement combustion chamber;

[0053] 51-first pipeline; 52-second pipeline; 53-third pipeline;

[0054] 6-thermocouple;

[0055] 7-temperature measuring element. DETAILED DESCRIPTION

[0056] The technical solutions of the present application will be described clearly and completely below in combination with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0057] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0058] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0059] In addition, the technical features involved in the different embodiments of the application described below can be combined with each other as long as there is no conflict.

[0060] Embodiment 1

[0061] The present embodiment provides a thermal shock test method for evaluating the life parameters of a flame tube, as shown in Figures 1 to 6 , comprising:

[0062] Step S1: pass the main road gas into the flame tube 1 to uniformly heat the cylinder body of the flame tube 1, and pass the impact gas to impact the preset area of the flame tube 1 to increase the local temperature of the preset area.

[0063] Step S2: record the temperature value of the preset area.

[0064] Step S3: control the temperature of the main road gas and the impact gas to make the flame tube 1 rise from the A working condition temperature to the B working condition temperature, and then drop from the B working condition temperature to the A working condition temperature.

[0065] Step S4: repeat step S3 until a crack of a preset size appears on the outer wall of the flame tube 1, record the number of repetitions of step S3 and obtain the life parameters of the flame tube 1.

[0066] The thermal shock test method for evaluating the service life parameter of the flame tube 1 used in the present application can realize uniform heating of the cylinder body of the flame tube 1 by using the main path gas to flow into the inside of the flame tube 1, and can simulate the wall temperature gradient of the flame tube 1 under the specified state by using the impact gas to heat the preset area arranged on the flame tube 1. Since the test object in the prior scheme is the engine as a whole, which includes the flame tube 1 and the components outside the flame tube 1, and the test object in the present method is only the flame tube 1 required for the test, only the requirements and conditions of the flame tube 1 during the test can be considered, the requirements and conditions of the components irrelevant to the flame tube 1 are reduced, and the test operation is simplified. The service life test of the flame tube can be accelerated by using the working condition to determine the failure mechanism (intergranular fracture or transgranular fracture) of the flame tube and the thermal shock cycle spectrum (triangular cycle or rectangular cycle). By flexibly adjusting the temperature of the main path gas and the impact gas, different gas environments can be simulated, the flame tube wall temperature under different working conditions can be achieved, the alternating stress of the flame tube under high temperature creep and low cycle can be investigated, and a method for evaluating the service life of the flame tube at the component level considering the actual working gas environment is provided. The test object used in the test method is the flame tube 1. Compared with the whole machine level life test, only the requirements and conditions of the flame tube during the test are considered, the requirements and conditions of the components irrelevant to the flame tube are reduced, and the test operation is simplified. A method for evaluating the service life of the flame tube at the component level considering the actual working gas environment is provided.

[0067] It can be explained that the A working condition provided in the above embodiment should be the A working condition shown in Figure 6 , and the B working condition should be the B working condition shown in Figure 6 . At the same time, Ta is the temperature of the thermocouple measured when the thermocouple is in the A working condition, and Tb is the temperature of the thermocouple measured when the thermocouple is in the B working condition. In addition, the speed of the temperature of the A working condition rising to the temperature of the B working condition, or the speed of the temperature of the B working condition falling to the temperature of the A working condition is k ℃ / s.

[0068] Further, the holding time t appearing in the cycle spectrum used by the thermal shock test device for evaluating the service life parameter of the flame tube provided by the present application should be determined according to the working condition of the flame tube applying the method of the present application.

[0069] The thermal shock test method for evaluating the service life parameter of the flame tube provided in the present embodiment, as shown in Figure 1 and Figure 2 , step S2 should include:

[0070] Step S21: welding a thermocouple 6 in the preset area.

[0071] Step S22: electrically connecting the thermocouple 6 and the temperature measuring element 7 to monitor the temperature of the thermocouple 6 through the temperature measuring element 7.

[0072] Further, in the present embodiment, as shown inFigure 2 and Figure 3 As shown in FIG. 2, step S21 is specifically:

[0073] Step S211: Take one hot spot in the preset area as the center of a circle and weld the thermocouple 6.

[0074] Step S212: Make an arc with R1, R2, ···, RN as the radius, and weld the thermocouple 6 at all four equal parts of the arc.

[0075] It can be explained that the thermal shock test method for evaluating the service life parameters of the flame tube provided in the embodiment does not limit the number of the thermocouples 6, which is 1+4N. Wherein, N is the number of the arcs. As one of the embodiments, in the embodiment, five thermocouples 6 are welded in the preset area on the outer wall of the flame tube 1. At this time, one thermocouple 6 is taken as the center of a circle, R is taken as the radius to make an arc, and the remaining four thermocouples 6 are welded at the four equal parts of the arc. The coordinates of the five thermocouples 6 are (X0, Y0), (X1, Y1), (X2, Y2), (X3, Y3) and (X4, Y4), and the corresponding temperatures are T0, T1, T2, T3 and T4, respectively.

[0076] The thermal shock test method for evaluating the service life parameters of the flame tube provided in the embodiment, in step S3, when the flame tube 1 is heated to the B working condition temperature, the holding should also be carried out, and the holding time is t. After holding, the flame tube 1 is cooled to the A working condition temperature.

[0077] It can be explained that the thermal shock test method for evaluating the service life parameters of the flame tube provided in the embodiment, in step S3, in the process of heating, the wall temperature of the flame tube 1 needs to reach the B working condition temperature.

[0078] Further, the thermal shock test method for evaluating the service life parameters of the flame tube provided in the embodiment, in step S3, in the process of cooling, the wall temperature of the flame tube 1 needs to reach the A working condition temperature.

[0079] The thermal shock test method for evaluating the service life parameters of the flame tube provided in the embodiment, in step S4, the preset size of the crack on the outer wall of the flame tube 1 should be less than or equal to 1mm. As one of the embodiments, in the embodiment, the preset size is selected to be 1mm.

[0080] Embodiment 2

[0081] The embodiment provides a thermal shock test device for evaluating a flame tube life parameter, which is used for performing the thermal shock test method for evaluating the flame tube life parameter provided in the embodiment 1, and comprises a casing 2, a main combustion chamber 3 and a shock combustion chamber 4. The casing 2 is suitable for accommodating a flame tube 1 sample; a flame outlet of the main combustion chamber 3 passes through the casing 2 through a first pipeline 51 and extends to the inside of the flame tube 1; and a flame outlet of the shock combustion chamber 4 passes through the casing 2 through a second pipeline 52 and extends to a preset region of the outer wall of the flame tube 1.

[0082] It can be explained that the thermal shock test device for evaluating the flame tube life parameter provided in the embodiment does not limit the material of the first pipeline 51 and the second pipeline 52, and in order to be consistent with the actual situation, the first pipeline 51 and the second pipeline 52 are made of high-temperature-resistant ceramic pipes.

[0083] The thermal shock test device for evaluating the flame tube life parameter provided in the embodiment does not limit the material of the casing 2, and in order to facilitate observation of crack of the flame tube 1 in the process of the test, the casing 2 is made of quartz glass.

[0084] It can be explained that the thermal shock test device for evaluating the flame tube life parameter provided in the embodiment, the inside of the casing 2 is communicated with an external cold gas source through a third pipeline 53, so that the casing 2 is cooled, and thus the phenomenon of explosion of the casing 2 in the process of temperature rise can be avoided.

[0085] It can be explained that the thermal shock test device for evaluating the flame tube life parameter provided in the embodiment, the preset region is welded with a thermocouple 6; and the thermal shock test device further comprises a temperature measuring element 7, an electric connection end of the temperature measuring element 7 is electrically connected with an electric connection end of the thermocouple 6, and the temperature measuring element 7 is used for receiving a thermoelectric electromotive force signal transmitted by the thermocouple 6 and converting the thermoelectric electromotive force signal into temperature.

[0086] It can be explained that the thermal shock test device for evaluating the flame tube life parameter provided in the embodiment further comprises a control element, an electric connection end of the control element is connected with an electric connection end of a switch element used for controlling the on-off of the flame outlet of the main combustion chamber 3 through a wire, and an electric connection end of the control element is connected with an electric connection end of a switch element used for controlling the on-off of the flame outlet of the shock combustion chamber 4 through a wire.

[0087] It can be explained that the thermal shock test device for evaluating the flame tube life parameter provided in the embodiment further comprises a feedback mechanism, and the feedback mechanism is used for feeding back the gas shock degree provided by the main combustion chamber 3 or the shock combustion chamber 4 according to the wall temperature of the flame tube 1.

[0088] In the test, constant temperature gas is supplied to the inside of the flame tube 1 through the main combustion chamber 3, so that the monitoring wall surface of the flame tube 1 reaches a specified average temperature. Then, gas impact is supplied to the preset area arranged on the outer wall of the flame tube 1 through the impingement combustion chamber 4 to form a hot spot, and five thermocouples 6 are welded in the preset area. Then, the temperature value of the thermocouples 6 is detected by the temperature measuring element 7, and compared with the temperature value specified in the A working condition, to determine whether the preset area reaches the temperature level of the A working condition. If the preset area reaches the temperature of the A working condition, the cycle spectrum is pushed to the B working condition, and the temperature value of the thermocouples 6 is detected by the temperature measuring element 7, to determine whether the preset area reaches the temperature level of the B working condition. If the preset area does not reach the temperature of the B working condition, the preset area is continuously heated until the preset area reaches the temperature of the B working condition. When the preset area reaches the temperature of the B working condition, the temperature is maintained. Then, the temperature of the gas output by the main combustion chamber 3 and the impingement combustion chamber 4 is lowered, and the temperature value of the thermocouples 6 is detected by the temperature measuring element 7, to determine whether the preset area reaches the temperature of the A working condition. If the preset area does not reach the temperature of the A working condition, the temperature is continuously lowered. If the preset area reaches the temperature of the A working condition, the cycle is completed. Then, the process of raising the temperature of the flame tube 1 from the temperature of the A working condition to the temperature of the B working condition, maintaining the temperature, and then lowering the temperature of the flame tube 1 from the temperature of the B working condition to the temperature of the A working condition is repeated, and the cycle number is recorded.

[0089] Obviously, the above-described embodiments are only examples for clearly illustrating the present application, and are not intended to limit the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments are not required to be exhausted, and the changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A thermal shock test method for evaluating a service life parameter of a flame tube, characterized in that, the thermal shock test method for evaluating a service life parameter of a flame tube uses a thermal shock test device for evaluating a service life parameter of a flame tube, the thermal shock test device comprising: a casing (2) adapted to accommodate a flame tube (1) sample; a main combustion chamber (3), a flame outlet of the main combustion chamber (3) passing through the casing (2) through a first pipeline (51) and extending to the inside of the flame tube (1); a shock combustion chamber (4), a flame outlet of the shock combustion chamber (4) passing through the casing (2) through a second pipeline (52) and extending to a preset region of the outer wall of the flame tube (1); the thermal shock test method for evaluating a service life parameter of a flame tube comprises: Step S1: passing the main route gas into the flame tube (1) to uniformly heat the flame tube (1) barrel, and passing the shock gas to the preset region of the flame tube (1) to increase the local temperature of the preset region; Step S2: recording the temperature value of the preset region; Step S3: controlling the temperature of the main route gas and the shock gas to make the flame tube (1) rise from the A working condition temperature to the B working condition temperature, and then drop from the B working condition temperature to the A working condition temperature; Step S4: repeating the step S3 until a crack of a preset size appears on the outer wall of the flame tube (1), recording the number of repetitions of the step S3 and obtaining the service life parameter of the flame tube (1); wherein, the step S2 comprises: Step S21: welding a thermocouple (6) in the preset region; Step S22: the thermocouple (6) is electrically connected with a temperature measuring element to monitor the temperature of the thermocouple (6) through the temperature measuring element; the step S21 specifically comprises: Step S211: taking any hot spot in the preset region as the center and welding a thermocouple (6); Step S212: making circular arcs with R1, R2, …, RN as the radius, and welding thermocouples (6) at all quarter points of the circular arcs. 2.The thermal shock test method for evaluating a service life parameter of a flame tube according to claim 1, characterized in that, in the step S3, the flame tube (1) used should also be subjected to a holding period when it is heated to the B working condition temperature, and the holding period is t. 3.The thermal shock test method for evaluating a service life parameter of a flame tube according to claim 1, characterized in that, in the step S4, the preset size of the crack on the outer wall of the flame tube (1) used should be less than or equal to 1mm. 4.The thermal shock test method for evaluating a service life parameter of a flame tube according to any one of claims 1-3, characterized in that, the inside of the casing (2) is in communication with an external cold gas source through a third pipeline (53). 5.The thermal shock test method for evaluating a service life parameter of a flame tube according to any one of claims 1-3, characterized in that, a thermocouple (6) is welded in the preset region; the thermal shock test device further comprises a temperature measuring element (7), an electrical connection end of the temperature measuring element (7) being electrically connected with an electrical connection end of the thermocouple (6), the temperature measuring element (7) being used to receive a thermoelectric electromotive force signal transmitted by the thermocouple (6) and convert the thermoelectric electromotive force signal into a temperature.

6. The thermal shock test method for evaluating the service life parameters of a flame tube according to any one of claims 1-3, characterized in that, The thermal shock test device further comprises a control element, an electric connection end of the control element is connected with an electric connection end of a switch element for controlling the on-off of the flame outlet of the main combustion chamber (3) through a wire, and an electric connection end of the control element is connected with an electric connection end of a switch element for controlling the on-off of the flame outlet of the impact combustion chamber (4) through a wire.

7. The thermal shock test method for evaluating the service life parameters of a flame tube according to claim 6, characterized in that, The thermal shock test device further comprises a feedback mechanism, the feedback mechanism is used for feeding back the gas impact degree provided by the main combustion chamber (3) or the impact combustion chamber (4) according to the wall temperature of the flame tube (1).

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