Device and method for testing high-temperature and high-pressure gas absorption cross section of aero-engine

Abstract

The invention discloses an aero-engine high-temperature and high-pressure gas absorption cross section testing device and method, and relates to the field of gas absorption cross section testing. A high-pressure system in the testing device is used for introducing target gas with set pressure into a high-temperature system; the target gas is experimental background gas or mixed gas of the experimental background gas and the gas to be detected; the high-temperature system is used for heating target gas to a set temperature; the optical system is used for introducing white light covering a visible light wave band into the high-temperature system; the target gas with the set temperature in the high-temperature system partially absorbs the white light, and the residual white light enters the optical system; the optical system is also used for detecting the entering white light, determining the light intensity of the gas absorption spectrum when the experimental background gas and the mixed gas are introduced, and determining the gas absorption section value under the set pressure and the set temperature based on the two light intensities; according to the invention, the complex gas atmosphere of the aero-engine can be simulated, and the accurate test of the wide-spectrum gas absorption cross section in the corresponding environment can be realized.

Description

Technical Field

[0001] The present application relates to the field of gas absorption cross-section testing, and in particular to a device and method for testing the high-temperature and high-pressure gas absorption cross-section of an aircraft engine. Background Art

[0002] The gas absorption cross section refers to the projected area of ​​the gas molecule perpendicular to the light path, which represents the strength of the gas molecule's light absorption ability. It is an important parameter for studying the absorption ability of gas molecules to light of a specific wavelength. It has a wide range of applications in gas spectroscopy, environmental monitoring, and temperature measurement. The corresponding gas absorption cross section data can be obtained based on the gas absorption spectrum obtained by accurate testing.

[0003] In the field of gas spectroscopy, studying the gas absorption cross section can obtain physical information about the internal structure of gas molecules. Due to the different absorptions caused by electron transitions and nuclear vibrations in gas molecules, the real absorption spectrum is often a peak with a certain width. The shape of different peaks is the line type, and the line strength is the intensity of the gas absorption spectrum. In the field of environmental monitoring, SO 2 、NO 2 Polluting gases such as carbon monoxide and phosphorus have their own unique gas characteristic absorption spectra. By testing the characteristic absorption spectra of different gases, a pollutant gas absorption cross-section database can be established, and the concentrations of different pollutant gases can be tested and monitored accordingly. In the field of temperature measurement, since the gas absorption spectrum is directly affected by temperature and pressure, the change pattern of the gas absorption cross-section with temperature and pressure can be obtained by testing the gas absorption spectrum at different temperatures and pressures, and the collision and temperature information in the gas molecules can be obtained from the corresponding spectral line intensity and spectral line shape.

[0004] However, the basis of the above applications is the accurate measurement of gas absorption cross sections at different temperatures and pressures. Currently, there are few methods for testing gas absorption cross sections, mainly differential optical absorption spectroscopy (DOAS) and tunable diode laser absorption spectroscopy (TDLAS).

[0005] Among them, the basic principle of DOAS technology is to separate the faster changing part and the slower changing part of the absorption cross section related to wavelength by testing transmittance combined with Beer-Lambert law and differential calculation method, and calculate the value of the absorption cross section based on the fast changing part. DOAS technology uses white light source, which can realize the measurement of the full visible light band of the spectrum. Its test requires the use of a long optical path gas absorption cell, and the test accuracy is high.

[0006] The basic principle of TDLAS technology is to use a tunable laser to emit light of a specific wavelength, scan the absorption spectrum of the gas sample, measure the change in light intensity, and thus determine the absorption cross section of the gas. TDLAS technology uses a tunable diode laser as a light source. Due to the extremely narrow line width of the laser light source, it can achieve high-precision testing of the absorption cross section of light of a specific wavelength.

[0007] However, the above-mentioned DOAS technology and TDLAS technology have the following disadvantages: the existing DOAS technology mirror group and absorption cell increase the optical path for testing. The principle of the absorption cell is to repeatedly reflect light through a high-reflectivity mirror to expand the optical path in a smaller space. Since the reflector cannot be used under high temperature and high pressure conditions, the DOAS technology is only suitable for gas absorption cross-section testing at lower temperatures and cannot meet the requirements of high temperature and high pressure testing. Although the TDLAS technology can realize gas absorption cross-section testing at high temperatures, its light source wavelength is single and cannot meet the needs of wide spectrum testing. Summary of the invention

[0008] The purpose of this application is to provide a device and method for testing the high-temperature and high-pressure gas absorption cross-section of an aircraft engine, which can simulate the complex fuel gas atmosphere conditions of an aircraft engine and realize accurate testing of the wide-spectrum gas absorption cross-section under the corresponding environment.

[0009] To achieve the above objectives, this application provides the following solutions:

[0010] In a first aspect, the present application provides a device for testing the high-temperature and high-pressure gas absorption cross section of an aircraft engine, comprising: a high-pressure system, a high-temperature system, and an optical system; the high-pressure system and the optical system are both connected to the high-temperature system; the test requirement for the aircraft engine is that the gas being tested meets a set pressure and a set temperature;

[0011] The high-pressure system is used to pass the target gas of set pressure into the high-temperature system; the target gas is the experimental background gas or mixed gas; the mixed gas is the gas obtained by mixing the experimental background gas with the gas to be tested;

[0012] The high temperature system is used to heat the target gas to a set temperature;

[0013] The optical system is used to introduce white light covering the visible light band into the high-temperature system; the target gas at a set temperature in the high-temperature system partially absorbs the white light, and the remaining white light enters the optical system;

[0014] The optical system is also used to detect the incoming white light, determine a first light intensity and a second light intensity, and determine the gas absorption cross-section value at a set pressure and a set temperature based on the first light intensity and the second light intensity; the first light intensity is the light intensity of the gas absorption spectrum detected when the experimental background gas is passed; the second light intensity is the light intensity of the gas absorption spectrum detected when the mixed gas is passed.

[0015] Optionally, the high-pressure system comprises: a first gas cylinder, a second gas cylinder, a first pressure measuring device, a second pressure measuring device, a first flow measurement control device, a second flow measurement control device, a mixing section, a transition section, a back pressure valve and a gas collecting device;

[0016] The first gas cylinder is used to contain the gas to be tested; the first gas cylinder is connected to the first flow measurement control device; the first pressure measurement device is arranged on the connection channel between the first gas cylinder and the first flow measurement control device; the first flow measurement control device is used to measure and control the flow of the gas to be tested; the first pressure measurement device is used to measure the pressure of the gas to be tested;

[0017] The second gas cylinder is used to contain the experimental background gas; the second gas cylinder is connected to the second flow measurement control device; the second pressure measurement device is arranged on the connection channel between the second gas cylinder and the second flow measurement control device; the second flow measurement control device is used to measure and control the flow of the experimental background gas; the second pressure measurement device is used to measure the pressure of the experimental background gas;

[0018] The output ends of the first flow measurement control device and the second flow measurement control device are both connected to the mixing section; the mixing section is connected to the air inlet of the high-temperature system through the transition section; the air outlet of the high-temperature system is connected to the gas collecting device through the back pressure valve; the mixing section is used to transfer the target gas to the transition section; the transition section is used to transfer the target gas entering from the mixing section to the high-temperature system; the back pressure valve is used to control the target gas in the high-temperature system to be at a set pressure; the gas collecting device is used to discharge the target gas that has absorbed part of the white light in the high-temperature system.

[0019] Optionally, the high temperature system comprises: a gas sample chamber, a heating system, a first quartz window, a second quartz window, a temperature measuring device and a temperature controller;

[0020] The first quartz window is arranged at one end of the gas sample chamber, and the second quartz window is arranged at the other end of the gas sample chamber; the first quartz window is used for receiving the white light covering the visible light band introduced by the optical system; the second quartz window is used for passing the remaining white light into the optical system after the target gas at a set temperature partially absorbs the white light; the heating system is surrounded on the outer wall of the gas sample chamber; the temperature measuring device is connected to the temperature controller; the temperature measuring device is used for measuring the temperature in the gas sample chamber and sending the measured temperature to the temperature controller; the temperature controller is used for controlling the temperature in the gas sample chamber to maintain at the set temperature by adopting a PID control method according to the measured temperature.

[0021] Optionally, the optical system comprises: a light source, a light guide rod, a detector and a processor;

[0022] The light source is used to emit white light covering the visible light band; the light guide rod is used to guide the white light into the high-temperature system; the detector is used to separate the white light emitted by the high-temperature system into monochromatic light, and detect the light intensity of the gas absorption spectrum in different bands of the monochromatic light to obtain a first light intensity and a second light intensity; the processor is used to determine the gas absorption cross-section value at a set pressure and a set temperature based on the first light intensity and the second light intensity.

[0023] Optionally, the high pressure system further comprises: a safety valve;

[0024] The transition section is connected to the air inlet of the high temperature system through the safety valve.

[0025] Optionally, the high temperature system further comprises: a thermal insulation layer, a first thermal insulation pipe plug and a second thermal insulation pipe plug;

[0026] The thermal insulation layer is arranged on the outer side of the heating system; the first thermal insulation pipe plug is arranged between one end of the gas sample chamber and the first quartz window, and the second thermal insulation pipe plug is arranged between the other end of the gas sample chamber and the second quartz window.

[0027] Optionally, the optical system further includes: a collimator; the collimator is located between the light source and the light guide rod.

[0028] Optionally, the detector includes a spectrometer and a camera;

[0029] The spectrometer is used to separate the white light emitted by the high temperature system into monochromatic light; the camera is used to detect the light intensity of the gas absorption spectrum in different bands of the monochromatic light to obtain the first light intensity and the second light intensity.

[0030] Optionally, the set pressure is 10 MPa; the set temperature is 1700°C.

[0031] In a second aspect, the present application provides a method for testing an aero-engine high-temperature and high-pressure gas absorption cross-section, which is used in the above-mentioned aero-engine high-temperature and high-pressure gas absorption cross-section testing device, and comprises:

[0032] Controlling the high-pressure system to pass the target gas of set pressure into the high-temperature system; the target gas is the experimental background gas or the mixed gas; the mixed gas is the gas obtained by mixing the experimental background gas with the gas to be tested;

[0033] Controlling the high temperature system to heat the target gas to a set temperature;

[0034] Controlling the optical system to introduce white light covering the visible light band into the high-temperature system; the target gas at a set temperature in the high-temperature system partially absorbs the white light, and the remaining white light enters the optical system;

[0035] The optical system is controlled to detect the incoming white light, determine a first light intensity and a second light intensity, and determine the gas absorption cross-section value at a set pressure and a set temperature based on the first light intensity and the second light intensity; the first light intensity is the light intensity of the gas absorption spectrum detected when the experimental background gas is introduced; the second light intensity is the light intensity of the gas absorption spectrum detected when the mixed gas is introduced.

[0036] According to the specific embodiments provided in this application, this application discloses the following technical effects:

[0037] The present application provides a device and method for testing the high-temperature and high-pressure gas absorption cross section of an aircraft engine, which can simulate the complex fuel gas atmosphere of an aircraft engine and accurately test the wide-spectrum gas absorption cross section. The set pressure and set temperature can be simulated by designing the high-pressure system and the high-temperature system to meet the high-temperature and high-pressure test requirements and realize the simulation of the complex fuel gas atmosphere conditions of an aircraft engine. The optical system introduces white light covering the visible light band into the high-temperature system, and detects the white light re-entering from the high-temperature system to determine the light intensity of the gas absorption spectrum when the experimental background gas and the mixed gas are introduced, and the gas absorption cross section value at the set pressure and set temperature is determined based on the two light intensities, thereby realizing the accurate test of the wide-spectrum gas absorption cross section under the complex fuel gas atmosphere conditions of the aircraft engine, and providing data support for gas concentration, temperature and other tests. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the embodiments of the present application 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 application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 A schematic diagram of the structure of a device for testing the high-temperature and high-pressure gas absorption cross-section of an aircraft engine provided in one embodiment of the present application;

[0040] Figure 2 for Figure 1 Schematic diagram of the structure of the medium and high temperature system;

[0041] Figure 3 for Figure 1 Schematic diagram of the structure of the medium and high voltage system and the optical system.

[0042] Figure numerals: high-pressure system-1, high-temperature system-2, optical system-3, heating system-4, first quartz window-5, second quartz window-6, temperature measuring device-7, temperature controller-8, high-voltage electrode sealing flange-9, thermal insulation layer-10, first thermal insulation pipe plug-11, second thermal insulation pipe plug-12, air inlet-13, air outlet-14, first gas cylinder-15, second gas cylinder-16, first pressure measuring device-17, second pressure measuring device-18, safety valve-19, back pressure valve-20, gas collecting device-21, first flow control device-22, first flow meter-23, second flow control device-24, second flow meter-25, light source-26, detector-27, collimating mirror-28. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0044] The gas absorption cross section is an important parameter for studying the absorption capacity of gas molecules for light of a specific wavelength, and is widely used in fields such as gas spectroscopy and temperature measurement. However, the current gas absorption cross section test is usually carried out at relatively low temperatures and pressures, which makes it difficult to meet the application requirements in high-temperature environments such as flue temperature measurement, gas turbines, and aircraft engines. Due to equipment limitations, there is currently no relevant research on absorption cross section testing in high-temperature and high-pressure environments. Therefore, this application proposes a device and method for testing the high-temperature and high-pressure gas absorption cross section of an aircraft engine, which solves the problem of testing the gas absorption cross section in high-temperature and high-pressure environments at the same time.

[0045] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0046] In an exemplary embodiment, Figure 1 As shown, a device for testing the high-temperature and high-pressure gas absorption cross section of an aircraft engine is provided, comprising: a high-pressure system 1, a high-temperature system 2 and an optical system 3; the high-pressure system 1 and the optical system 3 are both connected to the high-temperature system 2; the test requirement of the aircraft engine is that the gas to be tested meets the set pressure and the set temperature. For example, the set pressure can be 10MPa; the set temperature can be 1700℃.

[0047] The high pressure system 1 is used to pass a target gas of set pressure into the high temperature system 2; the target gas is an experimental background gas or a mixed gas; the mixed gas is a gas obtained by mixing the experimental background gas with a gas to be tested. The experimental background gas may be nitrogen.

[0048] The high temperature system 2 is used to heat the target gas to a set temperature.

[0049] The optical system 3 is used to introduce white light covering the visible light band into the high-temperature system 2 ; the target gas with a set temperature in the high-temperature system 2 partially absorbs the white light, and the remaining white light enters the optical system 3 .

[0050] The optical system 3 is also used to detect the incoming white light, determine the first light intensity and the second light intensity, and determine the gas absorption cross-section value at a set pressure and a set temperature based on the first light intensity and the second light intensity; the first light intensity is the light intensity of the gas absorption spectrum detected when the experimental background gas is passed; the second light intensity is the light intensity of the gas absorption spectrum detected when the mixed gas is passed.

[0051] An exemplary embodiment is given below to introduce the high temperature system 2.

[0052] In order to meet the temperature requirements, it is necessary to choose a suitable heating method. At present, there are three main high-temperature heating methods: high-temperature tube furnace heating, electric heating and shock tube heating. High-temperature tube furnace heating is to place the sample directly in the tube furnace, and heat the sample by heating the tube furnace (that is, the gas sample chamber). The temperature control of the tube furnace heating is precise, with an error of about 1°C, and the maximum temperature can reach 1700°C. The PID control method can be directly used for temperature control, which is easy to operate. In addition, the diameter of the tube furnace tube can be 30mm-500mm, and the length of the heating zone is between 150mm-1700mm, which basically meets the size requirements of the gas sample chamber. However, the tube furnace is large in size, and the pressure bearing capacity of the furnace tube is weak. It must maintain normal pressure during use, so the gas sample chamber structure has high requirements. In order to solve the above problems, the following are designed Figure 2 The high temperature system 2 is shown.

[0053] Figure 2 The high temperature system 2 shown uses tubular furnace heating, and the main body is a gas sample chamber with a total length of about 850 cm. The chamber uses high temperature alloy as material and can withstand higher temperatures and pressures.

[0054] See also Figure 2 The high temperature system 2 includes: a gas sample chamber, a heating system 4, a first quartz window 5, a second quartz window 6, a temperature measuring device 7 and a temperature controller 8.

[0055] The first quartz window 5 is arranged at one end of the gas sample chamber, and the second quartz window 6 is arranged at the other end of the gas sample chamber; the first quartz window 5 is used to receive the white light covering the visible light band introduced by the optical system 3; the second quartz window 6 is used to allow the remaining white light to enter the optical system 3 after the target gas at the set temperature partially absorbs the white light; the heating system 4 is surrounded on the outer wall of the gas sample chamber; the temperature measuring device 7 is connected to the temperature controller 8; the temperature measuring device 7 is used to measure the temperature in the gas sample chamber and send the measured temperature to the temperature controller 8; the temperature controller 8 is used to control the temperature in the gas sample chamber to maintain the set temperature by using the PID control method according to the measured temperature. Wherein, the heating system 4 can be a silicon molybdenum rod.

[0056] In another exemplary embodiment of the present application, the first quartz window 5 and the second quartz window 6 with high-voltage electrode sealing flanges 9 can be installed at both ends of the gas sample chamber by welding. The first quartz window 5 and the second quartz window 6 are both cooled by water to prevent the windows from cracking due to excessive temperature, which can meet the optical testing requirements. The diameter of the first quartz window 5 and the second quartz window 6 is about 50 mm.

[0057] In another exemplary embodiment of the present application, the high temperature system 2 further includes: a thermal insulation layer 10, a first thermal insulation pipe plug 11 and a second thermal insulation pipe plug 12; the thermal insulation layer 10 is arranged outside the heating system 4; the first thermal insulation pipe plug 11 is arranged between one end of the gas sample chamber and the first quartz window 5, and the second thermal insulation pipe plug 12 is arranged between the other end of the gas sample chamber and the second quartz window 6. The thermal insulation layer 10 is an alumina thermal insulation layer; the first thermal insulation pipe plug 11 and the second thermal insulation pipe plug 12 are both alumina pipe plugs.

[0058] The high temperature system 2 is further described using silicon molybdenum rods as the heating system 4 and aluminum oxide as the insulation material. To ensure the uniformity of the gas chamber temperature, the gas sample chamber is surrounded by a U-shaped silicon molybdenum rod for heating, and the two ends of the gas sample chamber and the surrounding gas sample chamber are insulated by aluminum oxide pipe plugs and aluminum oxide insulation layers. The heating section is about 500mm long and 40mm in diameter. During heating, the temperature of the silicon molybdenum rod itself can reach 1900°C, and the gas sample chamber is heated by radiation heat transfer, and the maximum heating temperature of the chamber can reach 1700°C.

[0059] In another exemplary embodiment of the present application, the temperature measuring device 7 may be an armored thermocouple. Specifically, in order to ensure accurate temperature testing during the gas absorption cross section test, a movable armored thermocouple with a sealed electrode is designed at the right end of the high temperature system 2 to accurately measure the temperature at different positions, and the temperature in the high temperature system 2 is accurately controlled on the computer control screen based on the temperature combined with the temperature controller 8, and the temperature control accuracy can reach 0.5°C. At the same time, the use of armored thermocouples can realize the measurement of the temperature in the constant temperature zone and ensure the temperature uniformity during the test. The high-pressure system 1 is placed under the main part of the high-temperature system 2, and the high-pressure system 1 realizes the pressure regulation in the gas chamber and the mixing of gas components.

[0060] An exemplary embodiment is given below to introduce the high-voltage system 1 .

[0061] See also Figure 3 The high-pressure system 1 includes: a first gas cylinder 15, a second gas cylinder 16, a first pressure measuring device 17, a second pressure measuring device 18, a first flow measurement control device, a second flow measurement control device, a mixing section, a transition section, a safety valve 19, a back pressure valve 20 and a gas collecting device 21.

[0062] The first gas cylinder 15 is used to contain the gas to be tested; the first gas cylinder 15 is connected to the first flow measurement control device; the first pressure measurement device 17 is arranged on the connection channel between the first gas cylinder 15 and the first flow measurement control device; the first flow measurement control device is used to measure and control the flow of the gas to be tested; the first pressure measurement device 17 is used to measure the pressure of the gas to be tested. Both the first gas cylinder 15 and the second gas cylinder 16 are high-pressure gas cylinders.

[0063] The second gas cylinder 16 is used to hold the experimental background gas; the second gas cylinder 16 is connected to the second flow measurement and control device; the second pressure measuring device 18 is arranged on the connecting channel between the second gas cylinder 16 and the second flow measurement and control device; the second flow measurement and control device is used to measure and control the flow of the experimental background gas; the second pressure measuring device 18 is used to measure the pressure of the experimental background gas.

[0064] The output ends of the first flow measurement and control device and the second flow measurement and control device are both connected to the mixing section; the mixing section is connected to one end of the transition section, and the other end of the transition section is connected to the air inlet 13 of the high-temperature system 2 through the safety valve 19; the air outlet 14 of the high-temperature system 2 is connected to the gas collecting device 21 through the back pressure valve 20; the mixing section is used to transfer the target gas to the transition section; the transition section is used to transfer the target gas entering from the mixing section to the high-temperature system 2; the back pressure valve 20 is used to control the target gas in the high-temperature system 2 to be at a set pressure; the gas collecting device 21 is used to discharge the target gas that has absorbed part of the white light in the high-temperature system 2.

[0065] Among them, the first flow measurement and control device includes a first flow control device 22 and a first flow meter 23 connected in sequence; the second flow measurement and control device includes a second flow control device 24 and a second flow meter 25 connected in sequence; the first pressure measuring device 17 is arranged on the connecting channel between the first gas cylinder 15 and the first flow control device 22; the second pressure measuring device 18 is arranged on the connecting channel between the second gas cylinder 16 and the second flow control device 24; the first pressure measuring device 17 and the second pressure measuring device 18 can both adopt pressure gauges.

[0066] The above-mentioned high-pressure system 1 sets the maximum pressure that can be reached in the gas sample chamber in the high-temperature system 2 by setting the back pressure valve 20. The maximum pressure regulation of the gas sample chamber can be achieved by continuously introducing gas into the gas sample chamber in combination with the flow meter. The pressure of the first gas cylinder 15 and the second gas cylinder 16 meets the pressure supply demand of the gas sample chamber. The experimental background gas is nitrogen, because nitrogen is a diatomic symmetrical molecule and does not participate in the absorption of light. Before the experiment, the gas to be tested needs to be mixed with nitrogen in advance. The gas distribution system consists of a first flow measurement control device, a second flow measurement control device, a mixing section and a filtering section, and each accessory is connected with a stainless steel pipe and a ferrule. The system is input by two gas channels, and the gas to be tested and nitrogen enter the mixing section through the corresponding flow measurement control device, and enter the gas sample chamber through the filtering section after mixing in the mixing section. In order to prevent the gas pressure in the gas sample chamber from being too high and unable to be discharged from the back pressure valve 20 in time, a safety valve 19 is set at the outlet of the transition section to control the inlet pressure of the gas sample chamber. In addition, since the exhaust gas has a high temperature, a gas collecting device 21 needs to be provided after the back pressure valve 20 to prevent leakage of high temperature gas.

[0067] An exemplary embodiment is given below to introduce the optical system 3.

[0068] See also Figure 3 The optical system 3 includes: a light source 26, a light guide rod, a detector 27 and a processor; the light source 26 is a white light source, used to emit white light covering the visible light band; the light guide rod is used to introduce the white light into the high-temperature system 2, and the light guide rod is coupled with the first quartz window 5, and the light guide rod can prevent the gas from absorbing light in an uneven temperature zone; the detector 27 is used to separate the white light emitted by the high-temperature system 2 into monochromatic light, and detect the light intensity of the gas absorption spectrum of different bands of the monochromatic light to obtain a first light intensity and a second light intensity; the processor is used to determine the gas absorption cross-section value at a set pressure and a set temperature based on the first light intensity and the second light intensity.

[0069] In another exemplary embodiment of the present application, the optical system 3 further includes: a collimator 28; the collimator 28 is located between the light source 26 and the light guide rod. The collimator 28 is used to collimate the white light emitted by the light source 26 and vertically enter the light guide rod to avoid scattering and other phenomena in the light path.

[0070] In another exemplary embodiment of the present application, the detector 27 includes a spectrometer and a camera; the spectrometer is used to separate the white light emitted by the high temperature system 2 into monochromatic light and realize detection of different bands; the camera is used to detect the light intensity of the gas absorption spectrum in different bands of the monochromatic light to obtain a first light intensity and a second light intensity.

[0071] In practical applications, when designing a high-temperature and high-pressure gas absorption cross-section test device for aircraft engines, the high-temperature system 2 and the high-pressure system 1 should meet the requirements of simulating the gas atmosphere and provide a stable high-temperature and high-pressure environment for experimental testing. The high-temperature system 2 should realize the functions of heating the gas and measuring the gas temperature, stably heating the gas in the gas sample chamber of the high-temperature system 2 to 1700°C and detecting the gas temperature. The main function of the high-pressure system 1 is to pressurize, purge and mix the gas, and its maximum pressure can reach about 10MPa. Therefore, the main design requirements of the high-temperature system 2 are to select appropriate heating and temperature measurement methods, and the main design requirements of the high-pressure system 1 are to accurately control the gas flow and maintain pressure stability.

[0072] The working principle of the above-mentioned aircraft engine high-temperature and high-pressure gas absorption cross-section test device is as follows: the design of the high-temperature system 2 and the high-pressure system 1 provides an accurate, known, and uniform high-temperature and high-pressure experimental environment for the gas absorption cross-section under high temperature and high pressure. The high-temperature system 2 can heat the gas to a maximum of 1700°C and achieve precise temperature adjustment through the heating system 4 and the gas sample chamber. The high-pressure system 1 can accurately simulate the fuel gas atmosphere by premixing the gas and mixing multiple gases to meet the requirements of aircraft engine fuel gas atmosphere testing. The optical system 3 can simultaneously measure the gas absorption cross-section covering the entire visible light band by using a white light source and a high-precision spectrometer. In addition, since the temperature gradient at both ends of the gas sample chamber is large, it will have a greater impact on the gas absorption cross-section test. Therefore, light guide rods and quartz windows are used at both ends to couple to avoid test errors caused by temperature non-uniformity.

[0073] In another exemplary embodiment of the present application, the processor determines the gas absorption cross-section value at a set pressure and a set temperature based on the first light intensity and the second light intensity, and the specific calculation formula is:

[0074]

[0075] Where, I(λ) represents the first light intensity; I 0 (λ) represents the second light intensity; L represents the length of the uniform temperature zone in the high temperature system 2; σ(λ) represents the gas absorption cross-section value at a set pressure and a set temperature; c represents the concentration of the gas to be measured in the mixed gas.

[0076] The high-temperature and high-pressure gas absorption cross-section testing device for aircraft engines of the above-mentioned embodiment has the advantages of being able to achieve high temperature, uniform temperature, high pressure, multi-component gas, and full-spectrum environment, and can realize / meet the requirements for accurate full-spectrum testing of gas absorption cross-sections under complex fuel gas atmosphere conditions of aircraft engines.

[0077] Based on the same inventive concept, the embodiment of the present application also provides a method for testing the high-temperature and high-pressure gas absorption cross section of an aircraft engine, which is implemented by using the above-mentioned high-temperature and high-pressure gas absorption cross section testing device of the aircraft engine. The implementation scheme for solving the problem provided by this method is similar to the implementation scheme recorded in the above-mentioned testing device, so the specific limitations in one or more embodiments of the method for testing the high-temperature and high-pressure gas absorption cross section of an aircraft engine provided below can be referred to the limitations of the high-temperature and high-pressure gas absorption cross section testing device of an aircraft engine, and will not be repeated here.

[0078] When using optical testing methods to test the fuel gas environment of aircraft engines, the gas absorption of light has a great impact, that is, the light energy is absorbed and converted into the internal energy of the fuel gas, causing the light intensity to weaken as the propagation distance increases. In order to make the optical testing technology practical, the impact of high-temperature and high-pressure fuel gas on optical performance must be considered to minimize the error caused by fuel gas absorption.

[0079] At present, most gas absorption cross-section tests have a low temperature and pressure range, lack consideration of temperature uniformity, and are difficult to meet the high temperature and high pressure environment testing requirements of aircraft engines. In addition, there is little research on the cross-absorption interference between gas components, and it is impossible to accurately judge the gas atmosphere absorption. Therefore, it is very necessary to develop a method that can simulate the high temperature and high pressure environment of gas and gas components and conduct absorption cross-section testing.

[0080] In an exemplary embodiment, a method for testing an aero-engine high-temperature and high-pressure gas absorption cross section is provided, comprising:

[0081] The high pressure system 1 is controlled to pass the target gas of set pressure into the high temperature system 2; the target gas is the experimental background gas or the mixed gas; the mixed gas is the gas obtained by mixing the experimental background gas with the gas to be tested.

[0082] The high temperature system 2 is controlled to heat the target gas to a set temperature.

[0083] The optical system 3 is controlled to pass white light covering the visible light band into the high-temperature system 2 ; the target gas with a set temperature in the high-temperature system 2 partially absorbs the white light, and the remaining white light enters the optical system 3 .

[0084] The optical system 3 is controlled to detect the incoming white light, determine the first light intensity and the second light intensity, and determine the gas absorption cross-section value at a set pressure and a set temperature based on the first light intensity and the second light intensity; the first light intensity is the light intensity of the gas absorption spectrum detected when the experimental background gas is passed; the second light intensity is the light intensity of the gas absorption spectrum detected when the mixed gas is passed.

[0085] In practical applications, a more specific implementation process of the high-temperature and high-pressure gas absorption cross-section test method for aircraft engines is as follows:

[0086] (1) Set the test temperature through the computer control screen of the temperature controller 8, turn on the power, heat the high temperature system 2 to the required test temperature by the silicon molybdenum rod, use the armored thermocouple to measure the temperature of the gas sample chamber, and confirm the uniform temperature zone length L.

[0087] (2) Open the second gas cylinder 16 containing nitrogen, the safety valve 19 and the back pressure valve 20, close the first gas cylinder 15 containing the gas to be tested, set the pressure of the back pressure valve 20 to the test pressure, set the pressure of the safety valve 19 to be slightly higher than the test pressure, introduce the experimental background gas nitrogen, and turn on the light source 26 after the temperature of the gas sample chamber stabilizes and the pressure reaches the test pressure. Use the spectrometer to test the light intensity when there is no absorption by the gas to be tested, that is, the first light intensity I(λ).

[0088] (3) Open the second gas cylinder 16 containing nitrogen, the safety valve 19 and the back pressure valve 20, open the first gas cylinder 15 containing the gas to be tested, control the flow rates of the two gases through the flow measurement control device and mix the gas to be tested in the mixing section. After the mixture is evenly mixed, it is passed into the gas sample chamber through the filtering section and purged for a period of time to determine whether the concentration of the gas to be tested in the gas sample chamber is stable. After the temperature is stable, the concentration c of the gas to be tested in the mixed gas is determined by the gas in the gas collecting device 21.

[0089] (4) Purge for a period of time. After the purge is completed and the temperature of the gas sample chamber is stable, turn on the light source 26, and use the spectrometer to test the light intensity after the gas to be tested is passed through, that is, the second light intensity I 0 (λ).

[0090] (5) Combined formula The Beer-Lambert law shown above gives the gas absorption cross section value σ(λ) for a set pressure and a set temperature.

[0091] The above-mentioned aircraft engine high temperature and high pressure gas absorption cross-section testing device and method have the following specific advantages:

[0092] 1) Simultaneously realize the test of wide spectrum absorption cross section of gas in high temperature and high pressure environment. This application solves the problem that traditional gas absorption cross section test technology cannot be applied to high temperature and high pressure environment and wide spectrum test at the same time through the design of high temperature system 2 and high pressure system 1, and designs an aero-engine gas absorption cross section test device and method.

[0093] 2) Long test time window. The existing TDLAS technology has a shock wave light test window time of only a few milliseconds, which is too short and difficult to test, and it is difficult to meet the needs of on-site testing. To address this problem, this application uses a hot isostatic pressing furnace heating method to achieve a stable temperature and pressure state for more than 1 hour, meeting actual testing needs.

[0094] 3) Good temperature uniformity. Although the existing TDLAS technology can realize the gas absorption cross-section test at high temperature, the temperature uniformity of the shock tube is difficult to guarantee, and the test results are highly limited. To address this problem, this application uses a high-voltage armored thermocouple design to accurately measure the length of the constant temperature zone, which can effectively ensure the temperature uniformity during the gas absorption cross-section test.

[0095] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0096] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application; at the same time, for those skilled in the art, according to the ideas of this application, 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 this application.

Claims

1. An aircraft engine high temperature and high pressure gas absorption cross section test device, characterized in that: The high-temperature and high-pressure gas absorption cross-section test device for an aircraft engine comprises: a high-pressure system, a high-temperature system and an optical system; the high-pressure system and the optical system are both connected to the high-temperature system; the test requirement for an aircraft engine is that the gas being tested meets a set pressure and a set temperature; The high-pressure system is used to pass the target gas of set pressure into the high-temperature system; the target gas is the experimental background gas or mixed gas; the mixed gas is the gas obtained by mixing the experimental background gas with the gas to be tested; The high temperature system is used to heat the target gas to a set temperature; The optical system is used to introduce white light covering the visible light band into the high-temperature system; the target gas at a set temperature in the high-temperature system partially absorbs the white light, and the remaining white light enters the optical system; The optical system is also used to detect the incoming white light, determine a first light intensity and a second light intensity, and determine the gas absorption cross-section value at a set pressure and a set temperature based on the first light intensity and the second light intensity; the first light intensity is the light intensity of the gas absorption spectrum detected when the experimental background gas is passed; the second light intensity is the light intensity of the gas absorption spectrum detected when the mixed gas is passed.

2. The aircraft engine high temperature and high pressure gas absorption cross section testing device according to claim 1, characterized in that: The high-pressure system comprises: a first gas cylinder, a second gas cylinder, a first pressure measuring device, a second pressure measuring device, a first flow measurement control device, a second flow measurement control device, a mixing section, a transition section, a back pressure valve and a gas collecting device; The first gas cylinder is used to contain the gas to be tested; the first gas cylinder is connected to the first flow measurement control device; the first pressure measurement device is arranged on the connection channel between the first gas cylinder and the first flow measurement control device; the first flow measurement control device is used to measure and control the flow of the gas to be tested; the first pressure measurement device is used to measure the pressure of the gas to be tested; The second gas cylinder is used to contain the experimental background gas; the second gas cylinder is connected to the second flow measurement control device; the second pressure measurement device is arranged on the connection channel between the second gas cylinder and the second flow measurement control device; the second flow measurement control device is used to measure and control the flow of the experimental background gas; the second pressure measurement device is used to measure the pressure of the experimental background gas; The output ends of the first flow measurement control device and the second flow measurement control device are both connected to the mixing section; the mixing section is connected to the air inlet of the high-temperature system through the transition section; the air outlet of the high-temperature system is connected to the gas collecting device through the back pressure valve; the mixing section is used to transfer the target gas to the transition section; the transition section is used to transfer the target gas entering from the mixing section to the high-temperature system; the back pressure valve is used to control the target gas in the high-temperature system to be at a set pressure; the gas collecting device is used to discharge the target gas that has absorbed part of the white light in the high-temperature system.

3. The aircraft engine high temperature and high pressure gas absorption cross section test device according to claim 1, characterized in that: The high temperature system comprises: a gas sample chamber, a heating system, a first quartz window, a second quartz window, a temperature measuring device and a temperature controller; The first quartz window is arranged at one end of the gas sample chamber, and the second quartz window is arranged at the other end of the gas sample chamber; the first quartz window is used for receiving the white light covering the visible light band introduced by the optical system; the second quartz window is used for passing the remaining white light into the optical system after the target gas at a set temperature partially absorbs the white light; the heating system is surrounded on the outer wall of the gas sample chamber; the temperature measuring device is connected to the temperature controller; the temperature measuring device is used for measuring the temperature in the gas sample chamber and sending the measured temperature to the temperature controller; the temperature controller is used for controlling the temperature in the gas sample chamber to maintain at the set temperature by adopting a PID control method according to the measured temperature.

4. The aircraft engine high temperature and high pressure gas absorption cross section testing device according to claim 1, characterized in that: The optical system comprises: a light source, a light guide rod, a detector and a processor; The light source is used to emit white light covering the visible light band; the light guide rod is used to guide the white light into the high-temperature system; the detector is used to separate the white light emitted by the high-temperature system into monochromatic light, and detect the light intensity of the gas absorption spectrum in different bands of the monochromatic light to obtain a first light intensity and a second light intensity; the processor is used to determine the gas absorption cross-section value at a set pressure and a set temperature based on the first light intensity and the second light intensity.

5. The aircraft engine high temperature and high pressure gas absorption cross section testing device according to claim 2, characterized in that: The high pressure system further comprises: a safety valve; The transition section is connected to the air inlet of the high temperature system through the safety valve.

6. The aircraft engine high temperature and high pressure gas absorption cross section test device according to claim 3, characterized in that: The high temperature system further comprises: a thermal insulation layer, a first thermal insulation pipe plug and a second thermal insulation pipe plug; The thermal insulation layer is arranged on the outer side of the heating system; the first thermal insulation pipe plug is arranged between one end of the gas sample chamber and the first quartz window, and the second thermal insulation pipe plug is arranged between the other end of the gas sample chamber and the second quartz window.

7. The aircraft engine high temperature and high pressure gas absorption cross section test device according to claim 4, characterized in that: The optical system further comprises: a collimator lens; the collimator lens is located between the light source and the light guide rod.

8. The aircraft engine high temperature and high pressure gas absorption cross section testing device according to claim 4, characterized in that: The detector includes a spectrometer and a camera; The spectrometer is used to separate the white light emitted by the high temperature system into monochromatic light; the camera is used to detect the light intensity of the gas absorption spectrum in different bands of the monochromatic light to obtain the first light intensity and the second light intensity.

9. The aircraft engine high temperature and high pressure gas absorption cross section testing device according to claim 1, characterized in that: The set pressure is 10 MPa; the set temperature is 1700°C.

10. A method for testing the high temperature and high pressure gas absorption cross section of an aircraft engine, characterized in that: The method for testing the high-temperature and high-pressure gas absorption cross section of an aircraft engine is used in the high-temperature and high-pressure gas absorption cross section testing device of any one of claims 1 to 9, and the method for testing the high-temperature and high-pressure gas absorption cross section of an aircraft engine comprises: Controlling the high-pressure system to pass the target gas of set pressure into the high-temperature system; the target gas is the experimental background gas or the mixed gas; the mixed gas is the gas obtained by mixing the experimental background gas with the gas to be tested; Controlling the high temperature system to heat the target gas to a set temperature; Controlling the optical system to introduce white light covering the visible light band into the high-temperature system; the target gas at a set temperature in the high-temperature system partially absorbs the white light, and the remaining white light enters the optical system; The optical system is controlled to detect the incoming white light, determine a first light intensity and a second light intensity, and determine the gas absorption cross-section value at a set pressure and a set temperature based on the first light intensity and the second light intensity; the first light intensity is the light intensity of the gas absorption spectrum detected when the experimental background gas is introduced; the second light intensity is the light intensity of the gas absorption spectrum detected when the mixed gas is introduced.

Images