A device, system and method for heating the main gas during thermal fatigue testing of turbine blades.

Abstract

This invention relates to the field of aero-engine turbine blade testing technology, specifically to a turbine blade thermal fatigue testing main gas heating device, system, and method. The device includes: a heat exchange combustion chamber, a heat exchanger, a main combustion chamber, and a fuel system. The outlet of the heat exchange combustion chamber is connected to the hot end inlet of the heat exchanger via a heat exchange intake pipe, and the hot end outlet of the heat exchanger is connected to a heat exchange exhaust pipe. The main gas intake pipe is connected to the cold end inlet of the heat exchanger, and the cold end outlet of the heat exchanger is connected to the main combustion chamber via a main combustion chamber intake pipe. The fuel system supplies fuel to both the heat exchange combustion chamber and the main combustion chamber. Working principle: Mainstream high-pressure gas enters the heat exchanger, is heated by the high-temperature combustion gas generated in the heat exchange combustion chamber to achieve a temperature rise of 400K, and then enters the main combustion chamber for final heating. This invention uses a fuel-driven heat exchanger instead of an electric heater for preheating, significantly reducing energy consumption and equipment complexity, and saving testing costs and space.

Description

Technical Field

[0001] This invention relates to the field of aero-engine turbine blade testing technology, and more specifically, to a turbine blade thermal fatigue testing main gas heating device, system, and method. Background Technology

[0002] In the research and development and verification of aero-engines, turbine blades, as core hot-end components, directly determine the overall reliability and service life of the engine through their performance stability. With the continuous improvement of the thrust-to-weight ratio of modern aero-engines, turbine inlet temperatures are constantly rising. During operation, turbine blades must simultaneously withstand complex aerodynamic loads generated by high-speed airflow and repeated thermal shocks from high-temperature combustion gases in the combustion chamber. The coupling effect of temperature and aerodynamic loads becomes a major cause of blade failure, especially during engine start-up, shutdown, or dynamic adjustment phases, when the temperature fluctuations on the inner and outer surfaces of the blades are drastic, resulting in a significant temperature gradient along the thickness direction. Furthermore, the non-uniform distribution of airflow on the blade surface further induces localized thermal stress concentration. This transient heat exchange process accumulates a large amount of thermal fatigue damage inside the blade, seriously threatening its structural integrity and long-term durability. Therefore, to accurately assess the ability of turbine blades to withstand alternating hot and cold environments, high-precision thermal fatigue tests must be conducted.

[0003] The core of turbine blade thermal fatigue testing lies in simulating the temperature alternation process throughout the engine's entire life cycle. By precisely controlling the temperature cycle and time parameters of the main airflow, the thermal load state of the blades during startup, operation, and shutdown is reproduced. During the test, the main airflow needs to be treated to the target temperature by a heating device to meet the testing requirements of different operating conditions. Traditional main air heating schemes generally adopt a combined structure of an electric heating subsystem, a fuel subsystem, and a main combustion chamber: the electric heating subsystem first preheats the main air, and then the preheated gas enters the main combustion chamber to mix and burn with aviation kerosene to achieve the final temperature increase. However, this technical approach has fundamental flaws. The electric heating process is extremely energy-intensive; the rated power of the electric heaters required for large-scale tests often reaches several megawatts, leading to continuously rising operating costs. The equipment is physically enormous; a typical megawatt-class electric heater is over ten meters long and weighs tens of tons, severely encroaching on test site space. The supporting systems are exceptionally complex, requiring additional high-voltage substations and voltage stabilization facilities, significantly increasing the difficulty of installation, commissioning, and maintenance. Due to the long cycle of thermal fatigue testing, the aforementioned problems make it difficult for traditional electric heating devices to meet the urgent needs of modern aviation testing in terms of energy efficiency, space utilization, and economy.

[0004] Therefore, how to provide a device, system, and method that can significantly reduce energy consumption, simplify equipment composition, reduce floor space, and at the same time meet the main gas heating requirements for turbine blade thermal fatigue testing is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The main objective of this invention is to propose a main gas heating device, system, and method for thermal fatigue testing of turbine blades. This invention has the advantages of reducing test energy consumption, reducing equipment size, eliminating the need for supporting facilities such as high-voltage power substations, reducing the total cost of the test cycle, improving the space utilization rate of the test site, and meeting the needs of modern aerospace turbine blade thermal fatigue testing.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a main gas heating device for a turbine blade thermal fatigue test, comprising a heat exchange combustion chamber, a heat exchanger, a main combustion chamber, and a fuel system; the outlet end of the heat exchange combustion chamber is connected to the hot end inlet of the heat exchanger via a heat exchange intake pipe, and the hot end outlet of the heat exchanger is connected to a heat exchange exhaust pipe; the main gas intake pipe is connected to the cold end inlet of the heat exchanger, and the cold end outlet of the heat exchanger is connected to the main combustion chamber via a main combustion chamber intake pipe; the fuel system supplies fuel to the heat exchange combustion chamber and the main combustion chamber respectively.

[0007] Furthermore, the heat exchange combustion chamber is an independent combustion chamber structure, set separately from the main combustion chamber. The heat exchange combustion chamber is used to generate high-temperature gas for heating the heat exchanger.

[0008] Furthermore, the fuel system can independently adjust the fuel flow rate supplied to the heat exchange combustion chamber and the main combustion chamber.

[0009] Furthermore, the heat exchanger is used to achieve a temperature rise of 400K for the mainstream high-pressure gas.

[0010] Furthermore, the heat exchanger is a partitioned heat exchanger, used to achieve heat transfer between the mainstream high-pressure gas and the high-temperature combustion gas, and the mainstream high-pressure gas and the high-temperature combustion gas do not come into direct contact.

[0011] Furthermore, both the heat exchange exhaust pipe and the heat exchange intake pipe are covered with an insulation layer.

[0012] Furthermore, the main combustion chamber intake duct is covered with an insulation layer.

[0013] Furthermore, a flow regulating valve is installed on the main gas intake pipe to control the flow rate of the mainstream high-pressure gas.

[0014] Secondly, the present invention provides a turbine blade thermal fatigue testing system, including the above-mentioned turbine blade thermal fatigue testing main gas heating device.

[0015] Thirdly, the present invention provides a method for heating the main gas in a turbine blade thermal fatigue test, using the aforementioned turbine blade thermal fatigue test main gas heating device, comprising the following steps: Start the fuel system, supplying fuel to the heat exchange combustion chamber and the main combustion chamber respectively and igniting it; The high-temperature combustion gas generated in the heat exchange combustion chamber enters the hot end of the heat exchanger through the heat exchange inlet pipe. The main high-pressure gas enters the cold end of the heat exchanger through the main gas inlet pipe, where it exchanges heat with the high-temperature gas to achieve a temperature rise of 400K. The low-temperature gas after heat exchange is discharged into the atmosphere through the heat exchange exhaust pipe; The preheated mainstream high-pressure gas enters the main combustion chamber through the main combustion chamber intake pipe, mixes with fuel and burns to achieve final heating; The heated gas is then output to the turbine blade test piece.

[0016] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows: The heat exchange combustion chamber generates high-temperature gas to provide a heat source for the heat exchanger. The mainstream high-pressure gas is preheated by the heat exchanger before being sent to the main combustion chamber for final heating. This replaces the high-power electric heating structure in the traditional solution, solving the problems of high energy consumption, large equipment size, and complex supporting facilities in traditional electric heating. It has the advantages of reducing test energy consumption, reducing equipment space occupation, eliminating the need for supporting facilities such as high-voltage power substation, reducing test operation and maintenance costs, improving space utilization, and meeting the needs of modern aerospace turbine blade thermal fatigue testing. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the main gas heating device for the thermal fatigue test of turbine blades provided by the present invention.

[0019] The following are the reference numerals: 1. Heat exchange combustion chamber; 2. Heat exchange exhaust pipe; 3. Heat exchanger; 4. Main air intake pipe; 5. Heat exchange intake pipe; 6. Main combustion chamber; 7. Main combustion chamber intake pipe. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0021] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0022] Traditional turbine blade thermal fatigue testing main gas heating devices typically employ electric heating for preheating the main gas. This method suffers from limitations such as high energy consumption, large footprint of the electric heater itself, and complex and costly auxiliary equipment. These problems result in extremely high energy consumption, complex equipment, and high operating costs for long-cycle testing, making it a technical problem urgently needing to be solved by those skilled in the art.

[0023] Firstly, this embodiment provides a main gas heating device for turbine blade thermal fatigue testing, combined with... Figure 1 As shown, the device includes a heat exchange combustion chamber 1, a heat exchanger 3, a main combustion chamber 6, and a fuel system. The outlet of the heat exchange combustion chamber 1 is connected to the hot end inlet of the heat exchanger 3 via a heat exchange intake pipe 5, and the hot end outlet of the heat exchanger 3 is connected to the heat exchange exhaust pipe 2. The main air intake pipe 4 is connected to the cold end inlet of the heat exchanger 3, and the cold end outlet of the heat exchanger 3 is connected to the main combustion chamber 6 via a main combustion chamber intake pipe 7. The fuel system supplies fuel to both the heat exchange combustion chamber 1 and the main combustion chamber 6. This device uses high-temperature combustion gas generated by fuel combustion for preheating, aiming to solve the problems of high energy consumption, complex equipment, large footprint, and high cost associated with existing electric heating methods.

[0024] In this embodiment, the heat exchange combustion chamber 1 generates high-temperature gas, which serves as a heat source for heating the heat exchanger 3. Its working principle involves releasing heat through fuel combustion to form high-temperature gas.

[0025] Heat exchanger 3 is used to achieve heat transfer, in which high-temperature gas and mainstream high-pressure gas to be heated exchange heat.

[0026] The main combustion chamber 6 is used to finally heat the mainstream high-pressure gas after it has been preheated by the heat exchanger 3, so that it reaches the temperature required for the test.

[0027] The fuel system supplies fuel to the heat exchange combustion chamber 1 and the main combustion chamber 6 to support the combustion process.

[0028] The heat exchange intake pipe 5 is used to guide the high-temperature combustion gas generated in the heat exchange combustion chamber 1 into the hot end inlet of the heat exchanger 3. The heat exchange intake pipe 5 is made of metal and has a smooth inner wall, which results in low frictional resistance.

[0029] The heat exchange exhaust pipe 2 is used to discharge the low-temperature gas after heat exchange in the heat exchanger 3.

[0030] The main gas inlet pipe 4 is used to guide the mainstream high-pressure gas into the cold end inlet of the heat exchanger 3.

[0031] The main combustion chamber intake pipe 7 is used to guide the mainstream high-pressure gas, which has been preheated by the heat exchanger 3, into the main combustion chamber 6.

[0032] In this embodiment, the heat exchange combustion chamber 1 is an independent combustion chamber structure, separated from the main combustion chamber 6. The heat exchange combustion chamber 1 is used to generate high-temperature combustion gas to heat the heat exchanger 3. If the heat exchange combustion chamber 1 is not separated from the main combustion chamber 6 and is set as an independent structure, the two will interfere with each other during operation, making it impossible to stably and independently generate the high-temperature combustion gas required to heat the heat exchanger 3. This would affect the stability and controllability of the main gas preheating, making it difficult to meet the requirements of the turbine blade thermal fatigue test for the accuracy of the main gas heating. The heat exchange combustion chamber 1 maintains a certain distance from the main combustion chamber 6 in physical space and is structurally independent, not sharing key combustion components or airflow channels. This separation ensures that the two combustion chambers do not affect each other during operation, and their respective combustion conditions can be adjusted independently, avoiding mutual interference caused by airflow or heat coupling.

[0033] By adopting the above structure, the core function of the heat exchange combustion chamber 1 is clarified, namely, the gas generated by the heat exchange combustion chamber 1 does not directly participate in the final heating of the turbine blade test piece, but serves as an intermediate heat source to indirectly heat the mainstream high-pressure gas through the heat exchanger 3, so as to achieve preheating of the mainstream high-pressure gas.

[0034] In some embodiments described above in this application, a fuel system is proposed to supply fuel to the heat exchange combustion chamber 1 and the main combustion chamber 6 respectively. However, in its implementation, if the fuel system cannot independently adjust the fuel flow rate supplied to the two combustion chambers, it is impossible to adjust the temperature of the high-temperature gas generated in the heat exchange combustion chamber 1 and the final heating temperature of the main combustion chamber 6 according to the actual test conditions. This makes it impossible to adapt to the different requirements of different tests for preheating and final heating temperatures, and it is also impossible to stably control the heat exchange process and the final heating process, making it difficult to ensure that the main gas heating result meets the requirements of the turbine blade thermal fatigue test.

[0035] In this regard, this application further proposes that the fuel system can independently adjust the fuel flow to the heat exchange combustion chamber 1 and the main combustion chamber 6. The fuel system has the ability to independently control the fuel flowing to the heat exchange combustion chamber 1 and the main combustion chamber 6. Specifically, this independent adjustment function can be achieved in the following ways: One approach is to configure independent fuel supply lines for the heat exchange combustion chamber 1 and the main combustion chamber 6, and to install independent flow control valves (e.g., electromagnetic proportional valves or servo control valves) and corresponding flow sensors on each line. Independent control units are used to precisely adjust each valve, thereby achieving independent control of the fuel flow. Another approach is to use a centralized fuel distribution system containing multiple independent fuel pumps or metering units. Each unit is specifically responsible for supplying fuel to one combustion chamber and can independently adjust its fuel supply according to instructions, for example, by controlling the fuel pump speed through frequency conversion or adjusting the stroke of the metering unit. Furthermore, independently adjustable nozzles or injectors can be installed on the fuel lines to change the fuel atomization and flow characteristics, thereby achieving fine-grained independent control of the fuel flow.

[0036] By adopting the above scheme, the fuel system can flexibly and precisely adjust the fuel flow rate supplied to the heat exchange combustion chamber 1 and the main combustion chamber 6 according to actual test requirements. Adjusting the fuel flow rate in the heat exchange combustion chamber 1 directly affects the temperature of the high-temperature combustion gas it generates, thereby precisely controlling the preheating effect of the heat exchanger 3 on the mainstream high-pressure gas, ensuring that the preheating temperature meets the test requirements and avoiding insufficient or overheating. Simultaneously, adjusting the fuel flow rate in the main combustion chamber 6 independently controls the final heating temperature of the mainstream high-pressure gas within the main combustion chamber 6, precisely matching the final temperature conditions required for different turbine blade thermal fatigue tests. This independent adjustment mechanism ensures that the temperature control of the preheating process and the final heating process do not interfere with each other, significantly improving the adaptability of the entire main gas heating device to different test conditions and enhancing the stability and control accuracy of the heating process, thus effectively guaranteeing the accuracy and reliability of the turbine blade thermal fatigue test results.

[0037] In this embodiment, the heat exchanger 3 is used to achieve a 400K temperature rise for the mainstream high-pressure gas. The temperature and flow rate of the high-temperature combustion gas generated in the heat exchange combustion chamber 1 can be adjusted by precisely controlling the fuel flow rate supplied to the heat exchange combustion chamber 1, thereby affecting the hot-end inlet temperature and heat load of the heat exchanger 3, ensuring that the heat exchanger 3 can stably provide a 400K temperature rise for the mainstream high-pressure gas. Specifically, controlling the temperature rise of the mainstream high-pressure gas after passing through the heat exchanger 3 to 400K provides sufficient preheating for the main gas. This allows the preheated main gas to more easily reach the final temperature required for the turbine blade thermal fatigue test to simulate the actual operating conditions of the engine when entering the main combustion chamber 6 for final heating, thus ensuring that the test can be carried out normally and accurate test results can be obtained. At the same time, this 400K temperature rise is not too high, avoiding unnecessary energy consumption increases and continuing the low-energy consumption advantage of this device compared to traditional electric heating methods. Furthermore, this temperature rise does not impose excessively stringent requirements on the structural design and high-temperature resistance of heat exchanger 3, effectively avoiding increased equipment design and manufacturing costs. Therefore, this solution can be well adapted to the overall architecture of the two-stage heating device, maintaining the advantages of low energy consumption, low cost, and simplified structure while meeting the core experimental requirements.

[0038] Heat exchanger 3 is used to heat the mainstream high-pressure gas. However, if the type of heat exchanger 3 and the contact method of the hot and cold heat exchange medium are not limited during the process, the high-temperature gas and the mainstream high-pressure gas may be directly mixed, which will change the original pressure parameters and composition of the mainstream high-pressure gas, affect the accuracy of the working conditions of the turbine blade cold and hot fatigue test, and fail to meet the test requirements for the main gas parameters.

[0039] In this embodiment, the heat exchanger 3 is a partitioned heat exchanger, which is used to realize the heat transfer between the mainstream high-pressure gas and the high-temperature combustion gas, and the mainstream high-pressure gas and the high-temperature combustion gas do not come into direct contact.

[0040] Specifically, a partitioned heat exchanger is a device that separates two fluids through a solid wall to achieve heat transfer. In this type of heat exchanger, heat is conducted from the high-temperature fluid to the low-temperature fluid through the wall, without the two fluids directly mixing. Partitioned heat exchangers can adopt various structural forms. For example, they can be plate heat exchangers, which use a series of thin metal plates to form flow channels, allowing the two fluids to flow alternately on both sides of the plates for heat exchange; they can also be shell-and-tube heat exchangers, where one fluid flows inside the tubes and the other flows outside the tubes, exchanging heat through the tube walls. Additionally, they can be coaxial heat exchangers or finned tube heat exchangers, etc. The core function of this heat exchanger 3 is to act as a heat exchange medium, efficiently transferring the heat energy carried by the high-temperature combustion gas generated in the heat exchange combustion chamber 1 to the mainstream high-pressure gas entering the cold end of the heat exchanger 3. The high-temperature combustion gas, as a heat source, flows in the hot-end flow channel of the heat exchanger 3, and its heat is conducted to the mainstream high-pressure gas through the heat exchange wall. The mainstream high-pressure gas, as the heated fluid, flows within the cold-end channel of heat exchanger 3, absorbing heat transferred from the wall surface, thereby increasing its temperature. Simultaneously, this technical solution emphasizes the requirement for media isolation during the heat exchange process; that is, inside heat exchanger 3, the mainstream high-pressure gas and the high-temperature combustion gas are always completely separated by a physical barrier (i.e., the heat exchange wall surface), preventing any form of mixing. This requires the structural design and manufacturing process of heat exchanger 3 to ensure good sealing between its internal channels, preventing mutual penetration or mixing of the two gas media due to leakage or other reasons. For example, the integrity of the heat exchange wall surface and the isolation between the channels are ensured by employing welding, expansion joints, or gasket sealing methods.

[0041] In some embodiments described above, a scheme is proposed whereby high-temperature combustion gas is generated in the heat exchange combustion chamber 1, sent to the heat exchanger 3 via the heat exchange intake pipe 5 to heat the main gas, and then discharged via the heat exchange exhaust pipe 2 to preheat the main gas, replacing the original electric preheating method and reducing energy consumption. However, during its implementation, the high-temperature combustion gas easily loses a large amount of heat to the outside when transported in the heat exchange intake pipe 5 and the heat exchange exhaust pipe 2, causing the temperature of the high-temperature combustion gas entering the heat exchanger 3 to drop. This not only wastes the heat energy generated by the combustion of fuel in the heat exchange combustion chamber 1, but also reduces the heat exchange effect of the heat exchanger 3, making it impossible to guarantee a sufficient temperature rise for the mainstream high-pressure gas entering the heat exchanger 3, affecting the final heating effect of the main gas, and failing to meet the requirements of turbine blade thermal fatigue testing.

[0042] In this regard, this application further proposes that both the heat exchange exhaust pipe 2 and the heat exchange intake pipe 5 are covered with an insulation layer. An insulation layer is a material or structure used to reduce heat transfer; its main function is to reduce heat conduction, heat convection, and heat radiation, thereby maintaining the internal temperature of the covered object. The insulation layer can be composed of various materials with low thermal conductivity, such as aluminum silicate fiber, glass wool, rock wool, aerogel, or polyurethane foam. These materials form a large number of non-flowing air layers through their internal microporous structure or interwoven fibers, effectively hindering heat conduction and convection.

[0043] By covering the heat exchange inlet pipe 5 and the heat exchange outlet pipe 2 with an insulation layer, heat exchange heat exchange gas exchange can be effectively blocked from heat exchange between the high-temperature gas and the external environment. Specifically, the insulation layer on the heat exchange inlet pipe 5 can prevent the high-temperature gas generated in the heat exchange combustion chamber 1 from losing too much heat during the process of being transported to the hot end of the heat exchanger 3, thereby ensuring that the high-temperature gas entering the hot end of the heat exchanger 3 maintains a sufficiently high temperature, providing a sufficient and stable heat source for the heat exchanger 3, and thus ensuring the preheating effect of the mainstream high-pressure gas. At the same time, the insulation layer on the heat exchange outlet pipe 2 can prevent the low-temperature gas after heat exchange from losing a large amount of residual heat to the external environment during the discharge process. This not only reduces unnecessary heat energy waste and improves the energy utilization efficiency of the entire system, but also prevents excess heat from spreading and affecting the normal operation of other components of the device and the stability of the test environment. Therefore, this technical solution effectively solves the problem of heat loss during high-temperature gas transmission, ensures the heat exchange efficiency and preheating effect of heat exchanger 3, thereby meeting the precise requirements of turbine blade thermal fatigue test for main gas heating, significantly reducing energy consumption, and improving the reliability and stability of the test.

[0044] Similarly, this application further proposes that the main combustion chamber intake pipe 7 is covered with an insulation layer, which can effectively block heat transfer between the preheated mainstream high-pressure gas inside the pipe and the external environment. This insulation structure significantly reduces the heat loss of the gas to the external environment during transportation, thereby ensuring that the mainstream high-pressure gas entering the main combustion chamber 6 can maintain a temperature close to the preset preheating temperature. In view of this, this technical solution not only helps to stabilize the gas temperature finally output to the turbine blade test piece, meeting the stringent requirements for temperature accuracy and stability in turbine blade thermal fatigue testing, thus improving the accuracy of test results; at the same time, due to the reduction of heat loss, the main combustion chamber 6 does not need to consume additional fuel to compensate for the temperature drop caused by pipe heat dissipation, thereby effectively reducing the overall energy consumption and operating cost of the test.

[0045] In this embodiment, a flow regulating valve is installed on the main gas inlet pipe 4 to control the flow rate of the mainstream high-pressure gas. This achieves controllability of the mainstream high-pressure gas flow rate. Since the main gas inlet pipe 4 is the inlet for the mainstream high-pressure gas to enter the entire heating device, installing a flow regulating valve here allows for direct control of the total flow rate of the main gas entering the entire device from the inlet end. This makes the adjustment process direct and convenient, eliminating the need for additional multi-stage adjustment structures in subsequent pipes, thus simplifying the overall structure of the device and enabling more precise control of the total amount of main gas entering the subsequent heating process. This flow regulating valve can flexibly adjust its opening according to the main gas flow rate parameters required for the current test, thereby changing the flow rate of gas that can pass through the pipe and ultimately obtaining the mainstream high-pressure gas flow rate that meets the requirements of the current test conditions. This ensures that the subsequent heating process can output the final gas that meets the test requirements, significantly improving the flexibility and accuracy of the test, and thus adapting to various turbine blade thermal fatigue test requirements.

[0046] Secondly, this embodiment provides a turbine blade thermal fatigue testing system, including a main gas heating device for turbine blade thermal fatigue testing. This system uses an optimized main gas heating device for turbine blade thermal fatigue testing as its core component. Given the advantages of this main gas heating device in terms of energy consumption, equipment structure, and floor space, it is integrated into the entire testing system, enabling the system to break free from the reliance on high-power electric preheating equipment in traditional solutions. Specifically, by using a heat exchange combustion chamber 1 to generate high-temperature combustion gas and utilizing a heat exchanger 3 to preheat the mainstream high-pressure gas, the traditional electric preheating method is effectively replaced, significantly reducing energy consumption during the test. Simultaneously, since the complex auxiliary equipment such as power transformers and voltage converters required for high-power electric heating is no longer needed, the structure of the entire testing system is greatly simplified, and the floor space is correspondingly reduced. Therefore, this system not only meets the various requirements for main gas heating in turbine blade thermal fatigue testing but also effectively reduces the overall operating cost of long-cycle thermal fatigue testing and can be directly used to conduct complete turbine blade thermal fatigue tests, obtaining test results that meet the requirements of actual service conditions.

[0047] Thirdly, this embodiment provides a method for heating the main gas in a turbine blade thermal fatigue test, the steps of which include: First, the fuel system is activated, supplying fuel to and igniting both the heat exchange combustion chamber 1 and the main combustion chamber 6. The fuel system is responsible for delivering fuel from the fuel reservoir to the heat exchange combustion chamber 1 and the main combustion chamber 6, atomizing it through nozzles, mixing it with air, and then burning it. Ignition can be achieved using a high-energy igniter or an electric spark plug. This step ensures that the heat exchange combustion chamber 1 and the main combustion chamber 6 start synchronously, providing a stable heat source for the subsequent two-stage heating process.

[0048] Secondly, the high-temperature combustion gas generated in the heat exchange combustion chamber 1 enters the hot end of the heat exchanger 3 through the heat exchange inlet pipe 5. The heat exchange combustion chamber 1, as an independent combustion chamber structure, primarily functions to generate high-temperature combustion gas, serving as a preheating heat source for the heat exchanger 3. The heat exchange inlet pipe 5 is used to guide the high-temperature combustion gas.

[0049] Next, the mainstream high-pressure gas enters the cold end of heat exchanger 3 through the main gas inlet pipe 4, where it exchanges heat with the high-temperature combustion gas, achieving a temperature rise of 400K. The mainstream high-pressure gas typically originates from a compressor or high-pressure gas source and is transported through the main gas inlet pipe 4. Heat exchanger 3 plays a crucial role in this process. It can be a partitioned heat exchanger, such as a plate-fin, shell-and-tube, or ceramic heat exchanger, to ensure efficient heat transfer between the mainstream high-pressure gas and the high-temperature combustion gas, while avoiding direct contact between the two, thus preventing contamination of the mainstream gas by the combustion gas. Through this heat exchange process, the mainstream high-pressure gas achieves a predetermined temperature rise of approximately 400K.

[0050] Subsequently, the temperature of the gas decreases after heat exchange and it is safely discharged through the heat exchange exhaust pipe 2.

[0051] Furthermore, the preheated mainstream high-pressure gas enters the main combustion chamber 6 through the main combustion chamber intake pipe 7, where it mixes and burns with fuel to achieve final heating. The main combustion chamber intake pipe 7 is responsible for delivering the mainstream high-pressure gas, preheated by the heat exchanger 3, to the main combustion chamber 6. The main combustion chamber 6 can adopt a structure similar to that of an aero-engine combustion chamber. Fuel is injected through nozzles provided by the fuel system, where it mixes thoroughly with the preheated high-pressure gas and burns, thereby raising the gas temperature to the final temperature required for the turbine blade thermal fatigue test.

[0052] Finally, the heated gas is output to the turbine blade test specimen. After two stages of heating, the high-temperature and high-pressure gas meets the test requirements in terms of temperature and pressure parameters. It is then precisely delivered to the turbine blade test specimen through a dedicated pipeline for thermal fatigue performance testing.

[0053] Through the above technical solution, this application provides an operating procedure adapted to a novel two-stage main gas heating device. This preheating process replaces the traditional electric heating method, significantly reducing energy consumption and eliminating the need for large-scale auxiliary equipment such as power transformers, thereby simplifying the equipment structure and reducing the footprint and weight of the equipment. The preheated mainstream high-pressure gas enters the main combustion chamber 6 for final heating. Since preheating has already provided most of the temperature rise, the load on the main combustion chamber 6 is reduced, fuel consumption is more reasonable, and the final temperature control is more precise. The low-temperature gas after heat exchange is discharged in a timely manner, ensuring the stable operation of the heat exchange process. Overall, this method can effectively guide the operation of the main gas heating device for turbine blade thermal fatigue testing. While meeting the main gas heating requirements of turbine blade thermal fatigue testing, it fully leverages the advantages of the device in reducing energy consumption, simplifying equipment, and reducing costs, providing an economical and efficient solution for long-cycle testing.

[0054] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention's specification and drawings under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A main gas heating device for thermal fatigue testing of turbine blades, characterized in that, It includes a heat exchange combustion chamber (1), a heat exchanger (3), a main combustion chamber (6), and a fuel system; The outlet end of the heat exchange combustion chamber (1) is connected to the hot end inlet of the heat exchanger (3) through the heat exchange air inlet pipe (5), and the hot end outlet of the heat exchanger (3) is connected to the heat exchange exhaust pipe (2). The main air intake pipe (4) is connected to the cold end inlet of the heat exchanger, and the cold end outlet of the heat exchanger (3) is connected to the main combustion chamber (6) through the main combustion chamber intake pipe (7). The fuel system supplies fuel to the heat exchange combustion chamber (1) and the main combustion chamber (6).

2. The main gas heating device for turbine blade thermal fatigue testing according to claim 1, characterized in that, The heat exchange combustion chamber (1) is an independent combustion chamber structure, which is set separately from the main combustion chamber (6). The heat exchange combustion chamber (1) is used to generate high-temperature gas to heat the heat exchanger (3).

3. The main gas heating device for turbine blade thermal fatigue testing according to claim 1, characterized in that, The fuel system can independently adjust the fuel flow rate supplied to the heat exchange combustion chamber (1) and the main combustion chamber (6).

4. The main gas heating device for turbine blade thermal fatigue testing according to claim 1, characterized in that, The heat exchanger (3) is used to achieve a temperature rise of 400K for the mainstream high-pressure gas.

5. The main gas heating device for turbine blade thermal fatigue testing according to claim 1, characterized in that, The heat exchanger (3) is a partitioned heat exchanger used to realize the heat transfer between the mainstream high-pressure gas and the high-temperature gas, and the mainstream high-pressure gas and the high-temperature gas do not come into direct contact.

6. The main gas heating device for turbine blade thermal fatigue testing according to claim 1, characterized in that, Both the heat exchange exhaust pipe (2) and the heat exchange intake pipe (5) are covered with an insulation layer.

7. The main gas heating device for turbine blade thermal fatigue testing according to claim 1, characterized in that, The main combustion chamber intake pipe (7) is covered with an insulation layer.

8. The main gas heating device for turbine blade thermal fatigue testing according to claim 1, characterized in that, The main gas inlet pipe (4) is equipped with a flow regulating valve to control the flow rate of the mainstream high-pressure gas.

9. A turbine blade thermal fatigue testing system, characterized in that, The device includes the main gas heating device for the thermal fatigue test of turbine blades as described in any one of claims 1 to 8.

10. A method for heating the main gas in a turbine blade thermal fatigue test, comprising the turbine blade thermal fatigue test main gas heating device as described in any one of claims 1 to 8, characterized in that, Includes the following steps: Start the fuel system to supply fuel to the heat exchange combustion chamber (1) and the main combustion chamber (6) respectively and ignite it; The high-temperature gas generated in the heat exchange combustion chamber (1) enters the hot end of the heat exchanger (3) through the heat exchange inlet pipe (5); The mainstream high-pressure gas enters the cold end of the heat exchanger (3) through the main gas inlet pipe (4) and exchanges heat with the high-temperature gas to achieve a temperature rise of 400K; The low-temperature gas after heat exchange is discharged into the atmosphere through the heat exchange exhaust pipe (2); The preheated mainstream high-pressure gas enters the main combustion chamber (6) through the main combustion chamber intake pipe (7) and mixes with fuel for combustion to achieve final heating; The heated gas is then output to the turbine blade test piece.

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