A high-temperature and high-speed flame generation device for simulating the service environment of an aircraft engine

Abstract

The present invention discloses a high-temperature and high-speed flame flow generating device for simulating the service environment of an aircraft engine, which relates to the technical field of simulating the service environment of an aircraft engine, and may include a plasma torch, wherein the plasma torch is connected to a nozzle, and a nozzle is arranged at the end of the nozzle; the plasma torch includes a heating system and a corrosive material supply system, wherein the heating system is used to provide a plasma flame jet, and the corrosive medium supply system is used to inject the corrosive medium into the plasma flame jet; the heating system and the corrosive material supply system are connected to a control device. The present invention can simulate the high-temperature, high-heat flux density, and corrosive service environment of a thermal barrier coating, and provides an important experimental platform for effectively evaluating the performance and failure mechanism of thermal barrier coatings and high-temperature structural materials in complex service environments.

Description

Technical Field

[0001] The invention relates to the technical field of aircraft engine service environment simulation, in particular to a high-temperature and high-speed flame flow generating device for simulating the aircraft engine service environment. Background Art

[0002] Aircraft engines have always been known as the "crown jewel", and their development level represents a country's comprehensive scientific and technological level and national defense strength. The thrust-to-weight ratio of aircraft engines is one of the important indicators to measure engine performance, and it is closely related to the maneuverability and economy of the aircraft. According to the Carnot cycle principle, increasing the inlet temperature before the turbine is the most important and most practical way to improve the thrust-to-weight ratio of the engine. At present, the three commonly used methods to increase the inlet temperature before the turbine are: developing new high-temperature structural materials, air film cooling technology, and thermal barrier coating technology. At present, the development of traditional single crystal high-temperature alloys and air film cooling technology has approached the limits of materials and processes, and thermal barrier coating technology has become the most practical way to further increase the temperature before the turbine.

[0003] The working environment of aircraft engines is extremely complex and harsh, including more than 20 types of loads such as high temperature, stress, and corrosive environment. Studies have shown that high-temperature oxidation, ablation, thermal expansion mismatch, particle erosion, and corrosive material erosion are the main causes of thermal barrier coating failure. The premature failure of thermal barrier coatings caused by various reasons is a key bottleneck restricting the development of coating applications. Establishing an engine service environment simulation platform, conducting in-depth research on the failure mechanism of thermal barrier coatings under various conditions, and improving and developing thermal barrier coatings based on this is the only way to break through the bottleneck.

[0004] At present, some work on simulating the service environment of aircraft engines has been carried out at home and abroad, mainly including coating thermal cycle, thermal gradient, corrosion environment, and heat, force, and environment coupling. Zhou Hong et al. (patent number: CN1818612A) proposed a thermal shock resistance device for thermal barrier coatings based on high-temperature resistance furnace heating, Yang Li et al. (patent publication number: CN103091237B) proposed a high-temperature flame spray gun device for simulating the corrosion service environment of thermal barrier coatings, Wang Ruijun et al. (patent publication number: CN105865961A) proposed a thermal shock test device for thermal barrier coatings in high temperature, thermal gradient and CMAS coupling service environment based on oxygen propane gas heating guns, Gong Shengkai et al. (patent publication number: CN1699994) disclosed a method of coupling infrared rapid heating equipment with corrosion environment and material mechanical properties experimental device to achieve thermal barrier coating heat, force, and corrosion service environment simulation. It can be found that most of the existing devices for simulating service environments are based on fuel and gas combustion flame heating or resistance heating, etc., with slow heating speed and low heating temperature; the service environment of aircraft engines is characterized by high temperature, high temperature gradient, high heat flux density, rapid heating and cooling, and high-speed particle erosion. It is difficult for existing simulation equipment to achieve these conditions at the same time.

[0005] Therefore, there is an urgent need to provide a new high-temperature and high-speed flame generation device that simulates the service environment of an aircraft engine to solve the above-mentioned problems existing in the prior art. Summary of the invention

[0006] The purpose of the present invention is to provide a high-temperature and high-speed flame flow generating device for simulating the service environment of an aircraft engine, so as to solve the problems existing in the above-mentioned prior art, and to simulate the high-temperature, high-heat flux density and corrosive service environment of a thermal barrier coating, thereby providing an important experimental platform for effectively evaluating the performance and failure mechanism of thermal barrier coatings and high-temperature structural materials in complex service environments.

[0007] To achieve the above-mentioned purpose, the present invention provides the following scheme: The present invention provides a high-temperature and high-speed flame flow generating device for simulating the service environment of an aircraft engine, comprising a plasma torch, wherein the plasma torch is connected to a nozzle, and a nozzle is arranged at the end of the nozzle; the plasma torch comprises a heating system and a corrosive material supply system, wherein the heating system is used to provide a plasma flame jet, and the corrosive medium supply system is used to inject a corrosive medium into the plasma flame jet; the heating system and the corrosive material supply system are connected to a control device.

[0008] Preferably, the heating system includes a combustion chamber, which is provided with a working gas injection port, a power supply cathode and a first anode, and the working gas injection port is used to inject the working gas into the combustion chamber of the plasma torch; the working gas is ionized between the power supply cathode and the first anode to form the plasma flame jet.

[0009] Preferably, a second anode is also provided behind the working gas injection port.

[0010] Preferably, the plasma torch further comprises a gas mixing chamber, the rear of the combustion chamber is connected to the gas mixing chamber, and the gas mixing chamber is connected to the nozzle; and a compressed air injection port is provided on the gas mixing chamber.

[0011] Preferably, the corrosive medium supply system includes a liquid injection port and a powder delivery port, the liquid injection port is arranged at the junction of the mixing chamber and the nozzle, and is used to inject liquid corrosive medium; the powder delivery port is arranged at the outlet of the nozzle, and is used to inject solid particulate corrosive medium.

[0012] Preferably, the liquid corrosive medium includes sea salt solution, kerosene or CMAS suspension, and the solid particle corrosive medium includes CMAS solid particles or Al 2 O 3 Solid particles.

[0013] Preferably, four liquid injection ports are provided, and the four liquid injection ports are evenly distributed along the circumference of the junction between the gas mixing chamber and the nozzle.

[0014] Preferably, it also includes a cooling system, and the cooling system is used to cool the combustion chamber and the nozzle.

[0015] Preferably, the cooling system comprises a cooling channel, a cold water inlet and a cold water outlet are arranged at both ends of the cooling channel, and the cooling channel is arranged around the combustion chamber or the nozzle.

[0016] Compared with the prior art, the present invention has achieved the following technical effects:

[0017] The present invention uses plasma flame jet as heat source, which can quickly raise the sample temperature to the target value, from 25°C to 1200°C within 10s, and has a high thermal conductivity of up to 150MW / m 2 The heat flux density can more realistically simulate the engine's high heat flux density and rapid temperature rise and fall service environment; the outlet gas flow rate of the invention is fast, and the solid particle erosion rate added to the plasma flame jet can be as high as 500m / s; the flame temperature of the plasma torch can be as high as 3500℃, and in the future it can be used for high-temperature performance evaluation and testing of new thermal barrier coatings and ultra-high temperature structural materials; compressed air can be used to atomize CMAS suspension, sea salt solution, and aviation kerosene solution and inject them into the plasma flame jet to simulate various corrosion environments of aircraft engines, and at the same time, high temperature, high heat flux density, high temperature gradient, high-speed particle erosion and other conditions can be coupled to achieve effective simulation of the complex service environment of aircraft engines. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 This is a schematic structural diagram of a high-temperature and high-speed flame flow generating device for simulating the service environment of an aircraft engine according to the present invention;

[0020] Among them, 1 is the power supply cathode, 2 is the first anode, 3 is the second anode, 4 is the gas mixing chamber, 5 is the liquid injection port, 6 is the nozzle, 7 is the nozzle, 8 is the powder delivery port, 9 is the first cooling channel, 11 is the second cooling channel, 12 is the third cooling channel, 10 is the air injection port, and 13 is the working gas injection port. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] Embodiment 1

[0024] like Figure 1 As shown, this embodiment provides a high-temperature and high-speed flame flow generating device for simulating the service environment of an aircraft engine, including a plasma torch, the plasma torch is connected to a nozzle 6, and a nozzle 7 is provided at the end of the nozzle 6; the plasma torch includes a heating system and a corrosive material supply system, the heating system is used to provide a plasma flame jet, and the corrosive medium supply system is used to inject the corrosive medium into the plasma flame jet; the heating system and the corrosive material supply system are connected to a control device.

[0025] In this embodiment, the heating system includes a combustion chamber, which is provided with a working gas injection port 13, a power supply cathode 1 and a first anode 2, and the working gas injection port 13 is used to inject the working gas into the combustion chamber of the plasma torch; the working gas is ionized between the power supply cathode 1 and the first anode 2 to form the plasma flame jet; and a second anode 3 is also provided behind the working gas injection port 13.

[0026] Specifically, the working gas of the heating system is air. By adjusting the current, voltage and gas flow of the working power supply, plasma flame jets of different temperatures and velocities can be provided. The sample is quickly heated to a high temperature environment under the condition of high heat flux density for simulation, and a thermal cycle simulation under a certain temperature gradient can be performed. Under the joint action of the temperature testing device and the control device, the closed-loop precise control of the temperature is achieved. Among them, the surface temperature of the sample is tested by an infrared thermometer, and the back temperature is tested by a K-type thermocouple. The front of the sample is heated by the flame, and the back is cooled by compressed air, thereby forming a certain temperature gradient on the surface and back of the sample. Among them, the control device adopts an existing controller, such as a computer or a PLC controller, etc. The control device is tested with an infrared thermometer and a K-type thermocouple, and the current, voltage, gas flow and control valve of the cooling nozzle 6 of the working power supply are controlled according to the received temperature signal.

[0027] In this embodiment, the plasma torch further includes a gas mixing chamber 4, the rear of the combustion chamber is connected to the gas mixing chamber 4, the gas mixing chamber 4 is connected to the nozzle 6, and a compressed air injection port 10 is provided on the gas mixing chamber 4. Specifically, the nozzle 6 of the nozzle 7 is connected to the plasma torch by screws, and nozzles 7 of different diameters are used according to the sample size and heat flux density requirements, such as 8 mm, 15 mm, 20 mm, 25 mm, etc.

[0028] In this embodiment, the corrosive medium supply system includes a liquid injection port 5 and a powder delivery port 8. The liquid injection port 5 is arranged at the junction of the gas mixing chamber 4 and the nozzle 6, and is used to inject liquid corrosive medium; the powder delivery port 8 is arranged at the outlet of the nozzle 7, and is used to inject solid particle corrosive medium. Specifically, the liquid corrosive medium includes sea salt solution, kerosene or CMAS suspension, and the solid particle corrosive medium includes CMAS solid particles or Al 2 O 3 Solid particles.

[0029] There are four liquid injection ports 5 , and the four liquid injection ports 5 are evenly distributed along the circumference of the junction between the gas mixing chamber 4 and the nozzle 6 .

[0030] In this embodiment, the liquid injection port 5 is provided with an atomizing nozzle 7, and the atomizing nozzle 7 is connected to a liquid inlet pipe. The corrosive medium supply system can input CMAS suspension, sea salt solution, and aviation kerosene solution through the liquid inlet pipe, and inject the compressed air into the plasma flame jet after being atomized by the atomizing nozzle 7. The amount of liquid corrosive medium added is controlled by a corrosion-resistant ZB-3WB glass rotor flowmeter (or other corrosion-resistant liquid flowmeters that meet the requirements) arranged at the liquid injection port 5. The compressed air is adjusted in pressure by a pressure valve arranged at the air injection port 10, thereby simulating various corrosive environments of aircraft engines. The corrosive medium supply system can also inject Al2O3 particles of different particle sizes into the plasma flame jet. 2 O 3 The particles are injected into the plasma flame via compressed air, simulating the environment where thermal barrier coatings and engine blades are eroded and eroded by high-temperature, high-speed particles.

[0031] In this embodiment, when the plasma torch is working, the plasma torch power is first selected, and the plasma torch working gas-air enters the plasma torch from the working gas injection port 13, and is ionized between the power supply cathode 1 and the first anode 2 to form a high-speed plasma flame jet. The plasma flame jet is amplified and stabilized by the second anode 3, enters the mixing chamber 4, and after mixing with the compressed air injected through the compressed air injection port 10, it is compressed by the nozzle 6 and ejected from the nozzle 7.

[0032] The liquid injection port 5 at the junction of the gas mixing chamber 4 and the nozzle 6 is used to inject corrosive substances such as sea salt solution and kerosene solution into the plasma flame flow, and the powder delivery port 8 at the outlet of the nozzle 7 can be used to inject CMAS, Al 2 O 3 Solid particles are injected into the flame, and the high-speed plasma flame carries the corrosive substances to the sample surface, heating, impacting and corroding the experimental samples.

[0033] In this embodiment, a cooling system is also included, and the cooling system is used to cool the combustion chamber and the nozzle 6; wherein the cooling system includes a cooling channel, and a cold water inlet and a cold water outlet are arranged at both ends of the cooling channel, and the cooling channel is arranged around the combustion chamber or the nozzle 6. Specifically, the cooling channel includes a third cooling channel 12 arranged at the combustion chamber, a second cooling channel 11, and a first cooling channel 9 arranged at the nozzle 6, and cooling is achieved by passing cooling water from the cold water inlet and the cold water outlet.

[0034] In this embodiment, the cooling system performs circulating water cooling on the combustion chamber and the nozzle 7 when working, and a cooling nozzle 6 is provided behind the sample. The cooling nozzle 6 is connected to an air source through a control valve for spraying compressed air, and the back of the sample is cooled by compressed air to simulate the service environment of the gradient temperature; after the heating is completed, the compressed air quickly cools the sample to achieve the conditions of simulating the thermal cycle;

[0035] The control device is connected to the heating system, the cooling system and the corrosive medium supply system to realize the simulation of high temperature, high heat flux density, gradient temperature, various corrosive environments and particle erosion environments.

[0036] The present invention uses plasma flame as heat source, which can quickly raise the sample temperature to the target value, from 25°C to 1200°C within 10s, and has a high thermal conductivity of up to 150MW / m 2 The heat flux density can more realistically simulate the engine's high heat flux density and rapid temperature rise and fall service environment; the outlet gas flow rate of the plasma torch is fast, and the solid particle erosion rate added to the plasma flame can be as high as 500m / s; the plasma flame temperature can be as high as 3500℃, which can be used for high temperature performance evaluation and testing of new thermal barrier coatings and ultra-high temperature structural materials in the future; compressed air can be used to inject CMAS suspension, sea salt solution, and aviation kerosene solution into the plasma flame jet through atomization, thereby simulating various corrosion environments of aircraft engines, and at the same time, it can couple high temperature, high heat flux density, high temperature gradient, high-speed particle erosion and other conditions to achieve effective simulation of the complex service environment of aircraft engines. The present invention can become an important experimental platform for evaluating the performance of thermal barrier coatings and high-temperature structural materials in engine service environments and studying their failure mechanisms.

[0037] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A high-temperature and high-speed flame flow generating device for simulating the service environment of an aircraft engine, characterized in that: The invention comprises a plasma torch, wherein the plasma torch is connected with a nozzle, and a nozzle is arranged at the end of the nozzle; the plasma torch comprises a heating system and a corrosive medium supply system, wherein the heating system is used to provide a plasma flame jet, and the corrosive medium supply system is used to inject the corrosive medium into the plasma flame jet, and the corrosive medium supply system comprises a powder delivery port, which is arranged at the outlet of the nozzle and is used to inject a solid particle corrosive medium; the heating system and the corrosive medium supply system are connected with a control device; the heating system comprises a combustion chamber, and the plasma torch further comprises a gas mixing chamber, the rear of the combustion chamber is connected with the gas mixing chamber, and the gas mixing chamber is connected with the nozzle; a compressed air injection port is arranged on the gas mixing chamber; the corrosive medium supply system further comprises a liquid injection port, which is arranged at the junction of the gas mixing chamber and the nozzle and is used to inject a liquid corrosive medium, wherein the liquid corrosive medium comprises a sea salt solution, kerosene or a CMAS suspension, and the solid particle corrosive medium comprises CMAS solid particles or Al2O3 solid particles.

2. The high-temperature and high-speed flame flow generating device for simulating the service environment of an aircraft engine according to claim 1, characterized in that: The combustion chamber is provided with a working gas injection port, a power cathode and a first anode. The working gas injection port is used to inject the working gas into the combustion chamber of the plasma torch; the working gas is ionized between the power cathode and the first anode to form the plasma flame jet.

3. The high-temperature and high-speed flame flow generating device for simulating the service environment of an aircraft engine according to claim 2, characterized in that: A second anode is also arranged behind the working gas injection port.

4. The high-temperature and high-speed flame flow generating device for simulating the service environment of an aircraft engine according to claim 2, characterized in that: There are four liquid injection ports, and the four liquid injection ports are evenly distributed along the circumference of the joint between the gas mixing chamber and the nozzle.

5. The high-temperature and high-speed flame flow generating device for simulating the service environment of an aircraft engine according to claim 1, characterized in that: Also included is a cooling system, which is used to cool the combustion chamber and the nozzle.

6. The high-temperature and high-speed flame flow generating device for simulating the service environment of an aircraft engine according to claim 5, characterized in that: The cooling system comprises a cooling channel, a cold water inlet and a cold water outlet are arranged at both ends of the cooling channel, and the cooling channel is arranged around the combustion chamber or the nozzle.

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