A combustion chamber ground ignition test system with visual observation and thermoacoustic synchronous measurement functions

Abstract

The application discloses a combustion chamber ground ignition test system with visual observation and thermal sound synchronous measurement functions and belongs to the technical field of solid rocket engine ground test. The system comprises a horizontal test table, a test engine, an optical visual window assembly, a combustion light radiation measuring device, a sensing measurement assembly and a high-frequency data acquisition and control system; the optical visual window assembly is installed on the side wall of the test engine, the combustion light radiation measuring device is arranged at a position opposite to the optical visual window assembly, and then the combustion condition of the combustion chamber gunpowder of the test engine is observed through the combustion light radiation measuring device; the sensing measurement assembly is installed on the other side wall of the test engine and is used for measuring the temperature and pressure of the combustion chamber of the test engine; compared with the prior art, the application can realize visual observation of the combustion process, thermal sound synchronous measurement and data saving under high-temperature, high-pressure and dangerous conditions, and improves the test safety and test integrity.

Description

Technical Field

[0001] This invention relates to the field of ground testing technology for solid rocket engines and related combustion devices, specifically to a ground ignition test system for a combustion chamber with functions of visual observation, temperature measurement, pressure measurement, and high-frequency data acquisition. Background Technology

[0002] In the research and development and evaluation of solid rocket engines and related combustion devices, ground ignition tests are a crucial means of verifying the engine's structural strength, combustion process, and the reliability of testing equipment. Because the combustion chamber is typically exposed to high temperature, high pressure, and high-speed gas flow, the testing process is inherently dangerous. Therefore, the testing system must not only possess reliable support, fixation, and explosion-proof capabilities, but also acquire as much complete combustion process information as possible while ensuring safety.

[0003] Traditional ground ignition test equipment mainly measures single parameters such as pressure, thrust, or temperature, lacking direct means of observing the flame morphology and combustion development process inside the combustion chamber. For combustion chamber tests requiring visualization, the observation window needs to simultaneously meet requirements for high temperature resistance, pressure resistance, sealing, and light transmission; if the window structure is not designed properly, it can easily cause glass damage, seal failure, or test safety risks.

[0004] Furthermore, the combustion chamber temperature is typically high, placing stringent requirements on temperature and pressure sensors in terms of installation sealing, heat resistance, dynamic response, and erosion resistance. Improper sensor installation can lead to sensor erosion, flame propagation, measurement interruption, or signal distortion. Simultaneously, the large volume of high-frequency temperature and pressure signals places high demands on data acquisition equipment, signal conditioning equipment, and real-time display software. Summary of the Invention

[0005] The purpose of this invention is to provide a combustion chamber ground ignition test system with visual observation and thermoacoustic synchronous measurement functions, which solves the problems of existing combustion chamber ground test devices having difficulty in visual observation under high temperature, high pressure and hazardous test conditions, insufficient reliability of sensor installation and sealing, and limited ability to acquire multi-source test information synchronously.

[0006] The technical solution to achieve the purpose of this invention is as follows: a ground ignition test system for a combustion chamber with visual observation and simultaneous thermoacoustic measurement functions, comprising a horizontal test bench, a test engine, an optical viewing window assembly, a combustion light radiation measuring device, a sensing measurement assembly, and a high-frequency data acquisition and control system; the test engine is mounted on the horizontal test bench, the optical viewing window assembly is mounted on the side wall of the test engine, and the combustion light radiation measuring device is positioned directly opposite the optical viewing window assembly, thereby observing the combustion of the propellant in the combustion chamber of the test engine through the combustion light radiation measuring device; the sensing measurement assembly is mounted on the other side wall of the test engine for measuring the temperature and pressure of the combustion chamber of the test engine; the high-frequency data acquisition and control system is connected to the combustion light radiation measuring device and the sensing measurement assembly for receiving and controlling the analysis of the data collected by the combustion light radiation measuring device and the sensing measurement assembly.

[0007] The significant advantages of this invention compared to existing technologies are:

[0008] (1) The present invention adopts a structure combining a horizontal test bench and a segmented test engine, which can achieve stable support, reliable fixation and convenient disassembly and assembly of the test engine in ground ignition test, and is suitable for combustion chamber ground ignition test under high temperature, high pressure and hazardous conditions.

[0009] (2) The present invention provides an observation window on the side wall of the test engine and forms an optical viewing window assembly by means of quartz glass and glass cover plate. While ensuring the sealing reliability and safety protection capability of the combustion chamber, it provides a high-temperature resistant and light-transmitting observation channel for optical measurement of the combustion process.

[0010] (3) The present invention sets up a combustion light radiation measurement device and uses it to collect characteristic light radiation intensity signals during the propellant combustion process through an optical viewing window component. This can be used to characterize the change in combustion heat release rate, thereby improving the observability and information integrity of the combustion process measurement.

[0011] (4) The present invention sets at least one set of sensing and measurement components at the test engine wall measurement position, which can simultaneously install fast response thermocouples and pressure sensors to realize the synchronous acquisition of temperature signals and pressure signals, thereby improving the integrity of ground ignition test data.

[0012] (5) The present invention is equipped with high-frequency data acquisition equipment, signal amplification equipment and high-frequency acquisition software, which can meet the requirements of high-frequency acquisition, real-time display and storage of temperature signal, pressure signal and combustion light radiation signal, and facilitate the monitoring of the test process and the retention of test data. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the overall structure of the combustion chamber ground ignition test system of the present invention.

[0014] The labels in the diagram represent the following: Ⅰ-Horizontal test bench, Ⅱ-Test engine, Ⅲ-Optical viewing window assembly, Ⅳ-Combustion light radiation measurement device, Ⅴ-Sensing measurement assembly, Ⅵ-High-frequency data acquisition and control system.

[0015] Figure 2 This is a cross-sectional schematic diagram of the engine used in the test of this invention.

[0016] The labels in the diagram represent: 1-sensor mounting hole, 2-observation window, 3-front combustion chamber, 4-rear combustion chamber, and 5-tail nozzle assembly. Detailed Implementation

[0017] The terminology used in this invention is for illustrative purposes only and is not intended to limit the scope of the invention.

[0018] Unless otherwise specified, all components, structures, and materials in this invention utilize commonly known components, structures, and materials in the art. For example, the horizontal test bench can be a known horizontal test bench with fireproof and explosion-proof functions; the combustion light radiation measuring device can be a known conventional industrial camera and a filter of suitable range; and the high-frequency data acquisition equipment, signal amplification equipment, and high-frequency acquisition software can be configured according to experimental requirements. The following description, in conjunction with the appendix... Figure 1 The following is a detailed description of some embodiments of the present invention.

[0019] The technical concept of this invention is as follows: Addressing the problem that existing combustion chamber ground ignition test devices cannot simultaneously achieve safe support, visual observation, synchronous temperature and pressure measurement, and high-frequency data acquisition under high temperature, high pressure, and hazardous conditions, this invention utilizes a horizontal test bench to ensure stable installation and safety protection of the test engine; a segmented structure consisting of a front combustion chamber, a rear combustion chamber, and a tailpipe assembly improves the ease of assembly and maintenance of the test engine; an optical viewing window assembly and a combustion light radiation measurement device on the side wall of the front combustion chamber enable visual observation of the combustion process; a sensing and measurement assembly on the other side wall of the front combustion chamber enables synchronous acquisition of thermoacoustic parameters; and a high-frequency data acquisition and control system enables synchronous acquisition, real-time display, and storage of test signals.

[0020] Following the above technical solution, specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments; all equivalent modifications or conventional improvements made based on the technical solution of the present invention fall within the protection scope of the present invention.

[0021] This embodiment provides a combustion chamber ground ignition test system with visual observation, thermo-acoustic synchronous measurement and combustion light radiation measurement functions, including a horizontal test bench I, a test engine II, an optical viewing window assembly III, a combustion light radiation measurement device IV, a sensing and measurement assembly V, and a high-frequency data acquisition and control system VI.

[0022] The system is built on an existing horizontal test bench. The horizontal test bench I includes a central frame, a central frame fixing channel steel and a thrust sensor fixing seat. It can provide a stable horizontal mounting foundation for the test engine II under hazardous test conditions and has fireproof, explosion-proof and other safety protection measures. It can be used for ground ignition tests of solid rocket engines or combustion chamber prototypes under hazardous conditions.

[0023] In this embodiment, the test engine II of the present invention is horizontally mounted on a horizontal test bench I. The test engine II includes, along the axial direction, a front combustion chamber 3, a rear combustion chamber 4, and a tail nozzle assembly 5. The front combustion chamber 3 is used to contain propellant. An observation window 2 is provided on one side wall of the front combustion chamber 3 for mounting an optical viewing window assembly III and providing an optical observation channel for the combustion light radiation measurement device IV. A sensor mounting hole 1 is provided on the other side wall of the front combustion chamber 3 for mounting a sensor measurement assembly V. The rear combustion chamber 4 is located between the front combustion chamber 3 and the tail nozzle assembly 5, for extending the gas flow channel and forming a subsequent combustion and flow space. The tail nozzle assembly 5 is used to form a gas exhaust channel. All parts are connected by flanges to form an integral combustion flow channel, which facilitates pre-test assembly, sealing inspection, and post-test disassembly and maintenance.

[0024] In this embodiment, the test engine II has an internal insulation layer. As a preferred embodiment, the insulation layer thickness is 10mm to 20mm. The insulation layer reduces the thermal impact of high-temperature combustion gases on the external metal casing, flange connection structure, and sensor mounting structure, thereby improving structural safety during the ground ignition test.

[0025] In this embodiment, at least one set of observation windows 2 is provided on the side of the front combustion chamber 3. As a preferred embodiment, the size of the observation windows 2 is determined according to the combustion chamber structure size, observation field of view and pressure sealing requirements, preferably with a long side of 70mm to 120mm and a short side of 60mm to 100mm.

[0026] The optical viewing window assembly III includes quartz glass and a glass cover plate disposed on the outside of the quartz glass. The quartz glass is embedded in the mounting groove of the observation window 2 to form a high-temperature resistant, light-transmitting observation channel. As a preferred embodiment, the thickness of the quartz glass is determined according to the structural dimensions of the observation window 2, the observation field of view, and the pressure-bearing and sealing requirements, preferably 10mm to 15mm. The glass cover plate is bolted to the outside of the observation window 2, and a high-temperature resistant sealing structure is provided between it and the quartz glass to compress, limit, and externally protect the quartz glass, thereby improving the sealing reliability and safety protection capability of the observation window 2 under high-temperature and high-pressure combustion gas environments. Through this structure, while ensuring the sealing reliability of the combustion chamber, the combustion light radiation measurement device IV can acquire characteristic light radiation signals of the propellant combustion process from outside the combustion chamber.

[0027] In this embodiment, the combustion light radiation measurement device IV is located outside the observation window section, directly opposite the observation window 2, and maintains a preset observation distance from the optical viewing window assembly III. The combustion light radiation measurement device IV includes an optical acquisition unit, a filter assembly, and a mounting bracket. The filter assembly is positioned on the incident light path of the optical acquisition unit and is used to select characteristic radiation bands related to heat release during propellant combustion. The optical acquisition unit is used to acquire the combustion light radiation intensity signal filtered by the filter assembly, thereby obtaining an optical measurement signal that characterizes the change in the propellant combustion heat release rate. Because the combustion light radiation measurement device IV is located outside the combustion chamber, this structure does not damage the combustion chamber's sealing structure and also improves the safety and reliability of the experimental measurement.

[0028] The optical acquisition unit in the combustion light radiation measurement device IV can be an industrial camera, photodetector, or high-speed optical acquisition device equipped with a filter assembly. As a preferred embodiment, the combustion light radiation measurement device IV uses an industrial camera in conjunction with a characteristic band filter. The transmission band of the characteristic band filter is determined based on the propellant combustion radiation characteristics, the response range of the optical acquisition unit, and the requirements for heat release rate characterization, preferably 300nm to 800nm. More preferably, the filter assembly includes a narrowband filter for acquiring characteristic radiation signals of combustion free radicals or combustion products. The combustion light radiation measurement device IV is fixed to the outside of the observation window 2 by a mounting bracket, with its optical axis corresponding to the light transmission direction of the observation window 2, to acquire characteristic light radiation intensity change signals during propellant combustion and further characterize changes in combustion heat release rate.

[0029] In this embodiment, at least one set of sensor mounting holes 1 are provided on the wall of the test engine II as sensor mounting positions, thereby fixing the sensor measurement component V. The sensor measurement component V includes a fast-response thermocouple and a pressure sensor, which enables the acquisition of temperature and pressure signals in the same combustion chamber area and facilitates unified connection with the high-frequency data acquisition and control system VI.

[0030] In this embodiment, the pressure sensor can be a piezoresistive pressure sensor or other pressure sensor that meets the requirements for combustion chamber pressure measurement, used to measure the pressure signal during the combustion chamber operation. The fast-response thermocouple can be a thermocouple that meets the requirements for high-temperature dynamic measurement. As a preferred option, the fast-response thermocouple uses high-temperature resistant thermocouple wire, preferably tungsten-rhenium thermocouple wire, suitable for high-temperature gas environments above 2000℃, with a response time of no more than 20ms, and can adapt to the temperature measurement requirements under high-temperature combustion environments.

[0031] In this embodiment, the high-frequency data acquisition and control system VI includes a high-frequency data acquisition device, a signal amplification device, and high-frequency acquisition software.

[0032] The high-frequency data acquisition equipment is used to receive electrical or digital signals output from the sensing and measurement component V and the combustion light radiation measurement device IV; the signal amplification equipment is used to condition and amplify the sensor signals; and the high-frequency acquisition software is used for setting sampling parameters, real-time data display, windowed smoothing processing, and data storage. As a preferred option, the sampling frequency of the high-frequency data acquisition equipment is 100kHz to 2MHz to meet the acquisition requirements of dynamic signals of combustion chamber temperature, pressure, and combustion light radiation.

[0033] In this embodiment, the high-frequency acquisition software can reduce the amount of real-time displayed data by using real-time data downsampling, windowing smoothing, or filtering, thereby improving the readability of the experimental process monitoring. The real-time data downsampling, windowing smoothing, or filtering is mainly used for real-time display and observation of the experimental process, and does not limit subsequent data processing methods.

[0034] When conducting ground ignition tests using the test system described in this invention, the following procedure can be followed: Before the test begins, the test engine II is installed on the horizontal test bench I, and the flange connection and sealing status between the front combustion chamber 3, the rear combustion chamber 4, and the tail nozzle assembly 5 are checked; the optical viewing window assembly III is installed at the observation window 2, the sensing and measurement assembly V is installed at the sensor mounting hole 1, and the sensing and measurement assembly V is connected to the high-frequency data acquisition and control system VI; the combustion light radiation measuring device IV is set up outside the observation window 2, and its optical axis is adjusted to face the observation window 2.

[0035] After the equipment setup is complete, check the ignition system, data acquisition system, and safety protection status of the test site, and close the explosion-proof door of the test room. At the start of the test, the participants confirm that all components of the test engine II and the measurement and control system are working normally, set the sampling frequency, and issue an ignition command after the igniter is deactivated, triggering the high-frequency data acquisition and control system VI and the combustion light radiation measurement device IV to begin recording.

[0036] After the engine finishes operating, data acquisition and optical signal recording are stopped, and the acquired temperature, pressure, and combustion light radiation intensity signals are saved. This process ensures that the test system can perform visual observation of the combustion process, synchronous temperature and pressure measurement, acquisition of combustion light radiation signals, and recording of the test process under hazardous conditions.

[0037] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention.

Claims

1. A combustion chamber ground ignition test system with visual observation and simultaneous thermoacoustic measurement functions, characterized in that, The system includes a horizontal test bench, a test engine, an optical viewing window assembly, a combustion light radiation measuring device, a sensing and measurement assembly, and a high-frequency data acquisition and control system. The test engine is mounted on the horizontal test bench, the optical viewing window assembly is mounted on the side wall of the test engine, and the combustion light radiation measuring device is positioned directly opposite the optical viewing window assembly to observe the combustion of the propellant in the combustion chamber of the test engine. The sensing and measurement assembly is mounted on the other side wall of the test engine to measure the temperature and pressure of the combustion chamber. The high-frequency data acquisition and control system connects the combustion light radiation measuring device and the sensing and measurement assembly to receive and analyze the data collected by these two components.

2. The combustion chamber ground ignition test system according to claim 1, characterized in that: The test engine includes, along the axial direction, a front combustion chamber, a rear combustion chamber, and a tail nozzle assembly. The front combustion chamber is used to contain the propellant, and at least one set of observation windows is provided on one side wall of the front combustion chamber for mounting optical viewing window assemblies and providing an optical observation channel for the combustion light radiation measurement device. At least one set of sensor mounting holes is provided on the other side wall of the front combustion chamber for mounting the sensing and measurement components; the rear combustion chamber is located between the front combustion chamber and the tail nozzle assembly to extend the gas flow channel and form a subsequent combustion and flow space; the tail nozzle assembly is used to form a gas exhaust channel.

3. The combustion chamber ground ignition test system according to claim 1, characterized in that: The test engine has an internal insulation layer with a thickness of 10mm to 20mm, which is used to reduce the thermal impact of high-temperature combustion gases on the external structure of the test engine.

4. The combustion chamber ground ignition test system according to claim 2, characterized in that: The optical viewing window assembly III includes quartz glass and a glass cover plate disposed on the outside of the quartz glass; the quartz glass is embedded in the viewing window mounting groove to form a high-temperature resistant light-transmitting observation channel; the glass cover plate is fixed to the outside of the viewing window by bolts, and a high-temperature resistant sealing structure is provided between the glass cover plate and the quartz glass to compress, limit, and provide external protection for the quartz glass.

5. The combustion chamber ground ignition test system according to claim 1, characterized in that: The combustion light radiation measurement device IV includes an optical acquisition unit and a filter assembly. The filter assembly is set in the incident light path of the optical acquisition unit and is used to select characteristic radiation bands related to heat release during propellant combustion. The optical acquisition unit is used to acquire the combustion light radiation intensity signal after being filtered by the filter assembly, thereby obtaining an optical measurement signal characterizing the change in the heat release rate of propellant combustion.

6. The combustion chamber ground ignition test system according to claim 1, characterized in that: The sensing and measurement component V includes thermocouples and pressure sensors, which acquire temperature and pressure signals within the same combustion chamber area and are uniformly connected to the high-frequency data acquisition and control system VI.

7. The combustion chamber ground ignition test system according to claim 6, characterized in that: The thermocouple uses tungsten-rhenium thermocouple wire, which is suitable for high-temperature gas environments above 2000℃, with a response time of no more than 20ms, and meets the temperature measurement requirements in high-temperature combustion environments.

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