CN110220665B - Safety protection method for temporary-impulse type supersonic wind tunnel low-range pressure measurement scanning valve - Google Patents
Safety protection method for temporary-impulse type supersonic wind tunnel low-range pressure measurement scanning valve Download PDFInfo
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- CN110220665B CN110220665B CN201910546315.9A CN201910546315A CN110220665B CN 110220665 B CN110220665 B CN 110220665B CN 201910546315 A CN201910546315 A CN 201910546315A CN 110220665 B CN110220665 B CN 110220665B
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- G01M9/00—Aerodynamic testing; Arrangements in or on wind tunnels
Abstract
The invention discloses a safety protection method of a temporary-flushing type supersonic wind tunnel low-range pressure-measuring scanning valve, aiming at protecting the low-range pressure-measuring scanning valve from equipment damage caused by pressure fluctuation when a wind tunnel is opened and closed and simultaneously realizing accurate measurement of the pressure of a measured model; in the stage of turning on and turning off the vehicle in the wind tunnel, the needle valve is pushed by controlling the air passage, so that the needle valve is positioned at the calibration end, the low-range pressure measurement scanning valve is protected, and in the stage of stabilizing the flow field of the wind tunnel, the needle valve is pushed by controlling the air passage, so that the needle valve is positioned at the measurement end, and the pressure of the measured model is accurately measured; compared with the traditional scanning valve protection system, the invention does not need expensive special protection devices and equipment, only needs to add the pneumatic electromagnetic valve and the low-range absolute pressure sensor, realizes the safety protection of the scanning valve and the accurate measurement of the pressure of the measured model, and has simple, convenient and quick protection method, time saving and labor saving; has the characteristics of simple and convenient operation, reliable operation, high efficiency and the like.
Description
Technical Field
The invention belongs to the technical field of aerodynamic wind tunnel tests, and particularly relates to a safety protection method of a temporary-flushing supersonic wind tunnel low-range pressure-measuring scanning valve, which is suitable for safety protection of the low-range pressure-measuring scanning valve during a wind tunnel pressure-measuring test.
Background
The pressure measurement test is an important content of a wind tunnel test, aims to provide original data of pneumatic load for structural strength calculation of an aircraft and components by measuring pressure distribution on the surface of an aircraft model, provides a basis for researching the pneumatic characteristics of the aircraft and the components of the aircraft and the streaming characteristics of the aircraft, and is an important means for verifying whether a numerical calculation method is accurate. At present, a method of distributing pressure measuring holes on the surface of a model is mainly adopted in a wind tunnel pressure measuring test, and the pressure of the surface of the model is transmitted to a pressure sensor through the pressure measuring holes and a pressure measuring pipeline for measurement. The electronic scanning valve pressure measuring system is a pressure measuring device commonly used in wind tunnel tests, can realize the acquisition and processing of multipoint pressure, and has the outstanding advantages of large number of measuring points, high scanning speed, high measuring accuracy and the like, wherein the scanning valve is a core device in the electronic scanning valve pressure measuring system, and the pressure value obtained by measurement is the pressure difference between the measuring end and the measuring reference end. In addition, the scanning valve is a multi-channel high-precision pressure scanner and consists of a plurality of silicon piezoresistive differential pressure sensors, the silicon pressure sensors are connected to a Wheatstone bridge by adopting piezoresistors, the generated voltage output is in direct proportion to the pressure input, and the acquired analog signals establish channel relation in a binary addressing mode through an amplifier and a multi-way change-over switch in the scanning valve so as to further realize the acquisition of multi-point pressure data.
In the existing wind tunnel pressure test, in order to avoid the damage of large pressure fluctuation generated by transient impact of a temporary-impulse type supersonic wind tunnel during starting and shutting down a scanning valve, a certain range allowance is reserved during selecting the pressure-measuring scanning valve to ensure that the measuring range is larger than the pressure value of the wind tunnel during starting and shutting down, namely, a high-range scanning valve is selected, for example, a scanning valve with the range of +/-45 psid, the measuring reference end of the scanning valve can be directly connected to the standard atmospheric pressure of 101.325kPa, and the pressure range measurable by the scanning valve reaches +/-310.275 kPa and is higher than the large pressure fluctuation generated by transient impact of the wind tunnel during starting and shutting down. However, in pressure measurement tests such as sonic boom near-field measurement, the absolute pressure value of the pressure measurement model is lower than the atmospheric pressure, and pressure fluctuation is small in the whole wind tunnel test process, and in order to ensure the pressure measurement precision, a low-range pressure measurement scanning valve, such as pressure measurement scanning valves with the ranges of ± 5psid, ± 1psid and ± 0.5psid, must be selected. The pressure measuring scanning valve with the low range can meet the following two problems that firstly, the pressure value of the wind tunnel during starting and closing is larger than the range of the pressure measuring scanning valve with the low range, which leads to the damage of the pressure measuring scanning valve, and secondly, the difference value between the pressure value of the pressure measuring point on the pressure measuring model and the atmospheric pressure is larger than the range of the pressure measuring scanning valve with the low range, which leads to the situation that the measuring reference end of the pressure measuring scanning valve can not be directly connected with the atmospheric pressure during the wind tunnel test. Due to the existence of the two problems, the low-range pressure measurement scanning valve must be protected in a targeted manner in a pressure measurement test so as to prevent the pressure value from exceeding the range of the scanning valve and causing the damage of the scanning valve.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a safety protection method of a temporary-flushing type supersonic wind tunnel low-range pressure measurement scanning valve, which has the advantages of simple operation, wide application range and strong practicability, and has two purposes:
firstly, the problem that the pressure value of the wind tunnel during starting and shutting down is larger than the range of the low-range pressure measuring scanning valve, so that the pressure measuring scanning valve is damaged is solved;
secondly, the problem that the difference value between the pressure value of the pressure measuring point on the pressure measuring model and the atmospheric pressure is larger than the range of the low-range pressure measuring scanning valve, so that the measuring reference end of the pressure measuring scanning valve cannot be directly connected to the atmospheric pressure is solved.
In order to solve the first problem, the technical scheme is as follows:
the scanning valve is provided with a measuring end and a calibrating end, and the scanning valve pushes a needle valve under different environments of the wind tunnel by controlling a gas circuit, so that the needle valve is positioned at the measuring end or the calibrating end, and the low-range pressure measuring scanning valve is protected.
On the basis of solving the first problem, a further scheme is proposed to solve the second problem, and the following technical scheme is adopted:
a tested model is arranged in a wind tunnel, a plurality of pressure measuring holes are arranged on the tested model, one of the pressure measuring holes is used as a reference pressure measuring point and is respectively connected to a measurement reference end of a scanning valve and a pneumatic electromagnetic valve through a gas pipe, the other end of the pneumatic electromagnetic valve is connected to a pressure measuring acquisition and control system through a low-range absolute pressure sensor, other pressure measuring holes on the tested model are respectively connected to a measuring end of the scanning valve through gas pipes, a calibration end of the scanning valve is connected to atmospheric pressure, and a control gas circuit of the scanning valve is connected to a standard control gas source.
The invention adopts the low-range absolute pressure sensor to measure the real absolute pressure value of the measurement reference end of the scanning valve, and the data measured by the scanning valve in the working state is the relative value of the measurement end and the measurement reference end, so the low-range absolute pressure sensor in the invention is needed to obtain the real pressure value of each measurement point of the measured model, and the low-range absolute pressure sensor refers to a sensor with the range less than the standard atmospheric pressure of 101.325 kPa.
The pneumatic electromagnetic valve is adopted in the invention to protect the low-range absolute pressure sensor, and the low-range absolute pressure sensor cannot be directly connected to the atmospheric pressure because the range of the low-range absolute pressure sensor is smaller than the standard atmospheric pressure. The main purpose of closing the pneumatic solenoid valve during the start and shut down of the wind tunnel is to protect the low range absolute pressure sensor.
Further, on the basis of the scheme, the following process is adopted:
when the wind tunnel is started, the pneumatic electromagnetic valve is closed, the air passage of the low-range absolute pressure sensor is blocked to protect the low-range absolute pressure sensor, the needle valve of the scanning valve is pushed to the calibration end by utilizing the control air passage of the scanning valve, the measurement end of the scanning valve is sealed by the valve body at the moment, the scanning valve works in a calibration mode, the measured pressure difference is the pressure difference between the calibration end and the calibration reference end, the pressure difference is zero, and the low-range pressure measurement scanning valve is protected;
when the flow field of the wind tunnel is stable, opening a pneumatic solenoid valve to connect a measuring gas circuit of the low-range absolute pressure sensor, pushing a needle valve of a scanning valve to a measuring end by using the control gas circuit of the scanning valve, working the scanning valve in a measuring mode at the moment, measuring the pressure difference between the measuring end and a measuring reference end, and determining the real pressure value of a pressure measuring point on a measured model as the sum of the measuring value of the scanning valve and the measuring value of the low-range absolute pressure sensor;
when the wind tunnel is closed, the pneumatic electromagnetic valve is closed, the air passage of the low-range absolute pressure sensor is blocked to protect the low-range absolute pressure sensor, the needle valve of the scanning valve is pushed to the calibration end by utilizing the control air passage of the scanning valve, the measurement end of the scanning valve is sealed by the valve body at the moment, the scanning valve works in the calibration mode, the measured pressure difference is the pressure difference between the calibration end and the calibration reference end, the pressure difference is zero, and the low-range pressure measurement scanning valve is protected.
In the above technical solution, the reference pressure measuring point is connected to the scanning valve and the pneumatic solenoid valve through a three-way connector.
In the above technical scheme, the calibration end of the scanning valve is connected to the atmospheric pressure outside the tunnel body of the wind tunnel through an air pipe.
In the above technical solution, the atmospheric pressure connected to the outside of the wind tunnel body further includes a calibration reference end.
In summary, due to the adoption of the technical scheme, the invention has the beneficial effects that:
compared with the traditional scanning valve protection system, the invention does not need special expensive protection devices and equipment, and only needs to add a pneumatic electromagnetic valve and a low-range absolute pressure sensor; the protection method is simple, convenient and quick, and saves time and labor;
the safety protection method of the low-range pressure measurement scanning valve fully utilizes the valve pushing function of the scanning valve, and has the characteristics of simple and convenient operation, reliable operation, high efficiency and the like.
Drawings
The invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic diagram of the safety protection of a temporary impulse type supersonic wind tunnel low-range pressure measurement scanning valve;
FIG. 2 is a wind tunnel test timing diagram of the low-range pressure measurement scanning valve safety protection method of the present invention;
wherein: the pressure measuring device comprises a pressure measuring model 1, a pressure measuring hole 2, a measuring point Ref 3, a pressure measuring gas path pipe 4, a three-way joint 5, a pneumatic solenoid valve 6, a low-range absolute pressure sensor 7, a pressure measuring scanning valve 8, a cable 9, an atmosphere 10, a standard control gas source 11 and a data acquisition and control system 12.
Detailed Description
All of the features disclosed in this specification, or all of the steps in any method or process so disclosed, may be combined in any combination, except combinations of features and/or steps that are mutually exclusive.
Any feature disclosed in this specification (including any accompanying claims, abstract and drawings), may be replaced by alternative features serving equivalent or similar purposes, unless expressly stated otherwise. That is, unless expressly stated otherwise, each feature is only an example of a generic series of equivalent or similar features.
As shown in fig. 1, the system schematic diagram of this embodiment includes a tested model, and a plurality of pressure measurement holes are disposed on the tested model, wherein one of the pressure measurement holes is used as a reference pressure measurement point and is respectively connected to a measurement reference end on a pressure measurement scanning valve and one end of a pneumatic electromagnetic valve through a three-way structure, and the other end of the pneumatic electromagnetic valve is connected to a pressure measurement acquisition and control system through a low-range absolute pressure sensor. Other pressure measuring holes of the tested model are sequentially connected to a measuring end on a pressure measuring scanning valve through an air pipe, a calibrating end on the pressure measuring scanning valve is connected to the atmospheric pressure outside the wind tunnel body, a calibrating reference end of the scanning valve is connected to the atmospheric pressure outside the wind tunnel body, and a control air passage of the scanning valve is connected to a standard control air source in the pressure measuring acquisition and control system.
The specific implementation process comprises the following steps:
assuming that a certain temporary impulse type supersonic wind tunnel has 15 pressure measuring modules with +/-5 psid measuring ranges (each pressure measuring module has 64 pressure measuring points), when a certain pressure measuring test is carried out, the number of the pressure measuring points on the model is 630 points.
The safety protection method of the temporary-impulse type supersonic wind tunnel low-range pressure-measuring scanning valve, as shown in fig. 2, comprises the following steps:
step one, according to the pressure measurement requirement of the 630 point of the test, 10 pressure measurement modules are selected from 15 pressure measurement modules, and a current electronic scanning valve pressure measurement system with the pressure measurement capability of 640 points is constructed;
selecting a measuring point Ref as a pressure reference point from each pressure measuring point 630 on the pressure measuring model, and connecting the measuring point Ref to the end A of a three-way joint, wherein the end B of the three-way joint is connected to the measuring reference end RRef of the used 10 scanning valves, the end C of the three-way joint is connected to one end of a pneumatic electromagnetic valve, and the other end of the pneumatic electromagnetic valve is connected to a low-range absolute pressure sensor; the scanning valve is ESP-64 of PSI company, the measuring range is +/-5 psid, the pneumatic electromagnetic valve is SMC VT307-5G-01, and the low-measuring-range absolute pressure sensor is Mensor CPT 6100;
step two, the rest 629 pressure measuring points on the pressure measuring model except the measuring point Ref are sequentially connected to the measuring end of the scanning valve;
step three, connecting control gas circuits C1 and C2 of the 10 scanning valves to a standard control gas source in a pressure measurement acquisition and control system; connecting the calibration ends of the 10 scanning valves to the atmospheric pressure outside the wind tunnel body, and connecting the calibration reference ends of the 10 scanning valves to the atmospheric pressure outside the wind tunnel body;
connecting the low-range absolute pressure sensor to a data acquisition and control system, and connecting the pneumatic electromagnetic valve to the data acquisition and control system;
step five, when the wind tunnel is started, the pneumatic electromagnetic valve is closed, and the air passage of the low-range absolute pressure sensor is blocked to protect the low-range absolute pressure sensor; the control gas circuit of the scanning valve is utilized to push all 10 scanning valves to a calibration end, the measurement ends of all the scanning valves are sealed by the valve body at the moment, the scanning valves work in a calibration mode, the measured pressure difference is the pressure difference between the calibration end and a calibration reference end, the pressure difference is basically zero, and the scanning valves are protected;
step six, when the flow field of the wind tunnel is stable, opening a pneumatic electromagnetic valve to connect a measurement air path of the low-range absolute pressure sensor; the control gas circuit of the scanning valve is utilized to push all 10 scanning valves to the measuring end, all the scanning valves work in a measuring mode at the moment, the measured value of the scanning valves is the pressure difference between the measuring end and the measuring reference end, and the real pressure value of the pressure measuring point on the pressure measuring model is the sum of the measured value of the scanning valve and the measured value of the low-range absolute pressure sensor;
step seven, when the wind tunnel is closed, the pneumatic electromagnetic valve is closed, and the air passage of the low-range absolute pressure sensor is blocked to protect the low-range absolute pressure sensor; and (3) pushing all the 10 used scanning valves to a calibration end by using a control gas circuit of the scanning valves, sealing the measurement end of each scanning valve by using a valve body, working all the scanning valves in a calibration mode, measuring the pressure difference between the calibration end and a calibration reference end, wherein the pressure difference is basically zero, and protecting the scanning valves.
In conclusion, the invention utilizes the valve pushing function of the scanning valve, and by adding the pneumatic electromagnetic valve and the low-range absolute pressure sensor, the safety protection of the temporary-impulse type supersonic wind tunnel low-range pressure measurement scanning valve is realized, and the accurate measurement of the pressure of the measured model is ensured
The invention is not limited to the foregoing embodiments. The invention extends to any novel feature or any novel combination of features disclosed in this specification and any novel method or process steps or any novel combination of features disclosed.
Claims (5)
1. A safety protection method for a temporary-flushing supersonic wind tunnel low-range pressure-measuring scanning valve is characterized in that the scanning valve is provided with a measuring end and a calibrating end, and is characterized in that the scanning valve pushes a needle valve under the control of a control gas circuit in different environments of a wind tunnel, so that the needle valve is positioned at the measuring end or the calibrating end, and the low-range pressure-measuring scanning valve is protected;
a measured model is arranged in the wind tunnel, a plurality of pressure measuring holes are arranged on the measured model, one of the pressure measuring holes is used as a reference pressure measuring point and is respectively connected to a measurement reference end of a scanning valve and a pneumatic electromagnetic valve through a gas pipe, the other end of the pneumatic electromagnetic valve is connected to a pressure measuring acquisition and control system through a low-range absolute pressure sensor, other pressure measuring holes on the measured model are respectively connected to a measuring end of the scanning valve through gas pipes, a calibration end of the scanning valve is connected to atmospheric pressure, and a control gas circuit of the scanning valve is connected to a standard control gas source;
the protection method comprises the following specific processes:
when the wind tunnel is started, the pneumatic electromagnetic valve is closed, the air passage of the low-range absolute pressure sensor is blocked to protect the low-range absolute pressure sensor, the needle valve of the scanning valve is pushed to the calibration end by utilizing the control air passage of the scanning valve, the measurement end of the scanning valve is sealed by the valve body at the moment, the scanning valve works in a calibration mode, the measured pressure difference is the pressure difference between the calibration end and the calibration reference end, the pressure difference is zero, and the low-range pressure measurement scanning valve is protected;
when the flow field of the wind tunnel is stable, opening a pneumatic solenoid valve to connect a measuring gas circuit of the low-range absolute pressure sensor, pushing a needle valve of a scanning valve to a measuring end by using the control gas circuit of the scanning valve, working the scanning valve in a measuring mode at the moment, measuring the pressure difference between the measuring end and a measuring reference end, and determining the real pressure value of a pressure measuring point on a measured model as the sum of the measuring value of the scanning valve and the measuring value of the low-range absolute pressure sensor;
when the wind tunnel is closed, the pneumatic electromagnetic valve is closed, the air passage of the low-range absolute pressure sensor is blocked to protect the low-range absolute pressure sensor, the needle valve of the scanning valve is pushed to the calibration end by utilizing the control air passage of the scanning valve, the measurement end of the scanning valve is sealed by the valve body at the moment, the scanning valve works in the calibration mode, the measured pressure difference is the pressure difference between the calibration end and the calibration reference end, the pressure difference is zero, and the low-range pressure measurement scanning valve is protected.
2. The safety protection method of the temporary-impulse type supersonic wind tunnel low-range pressure-measuring scanning valve according to claim 1, wherein the low-range absolute pressure sensor is used for measuring a pressure value of a reference end of the scanning valve.
3. The safety protection method of the temporary-impulse type supersonic wind tunnel low-range pressure measurement scanning valve according to claim 1, wherein the reference pressure measurement point is connected to the scanning valve and the pneumatic solenoid valve through a three-way connector.
4. The safety protection method of the temporary-impulse type supersonic wind tunnel low-range pressure measurement scanning valve according to claim 1, wherein the calibration end of the scanning valve is connected to the atmospheric pressure outside the wind tunnel body through an air pipe.
5. The safety protection method of the temporary rush type supersonic wind tunnel low-range pressure measurement scanning valve according to claim 4, wherein the atmospheric pressure connected to the outside of the wind tunnel body further comprises a calibration reference end.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110686858B (en) * | 2019-11-07 | 2021-02-26 | 中国空气动力研究与发展中心 | Sound explosion measurement wind tunnel test data processing method |
| CN111238759B (en) * | 2020-03-31 | 2021-07-13 | 中国空气动力研究与发展中心低速空气动力研究所 | Icing wind tunnel pressure measurement test method |
| CN112113740B (en) * | 2020-11-18 | 2021-02-09 | 中国空气动力研究与发展中心低速空气动力研究所 | Pressure measuring device, pressure measuring method and wind tunnel local airflow deflection angle measuring method |
| CN112461489B (en) * | 2020-11-25 | 2022-09-23 | 中国空气动力研究与发展中心高速空气动力研究所 | Electronic scanning valve reference pressure control system for low-pressure measurement and application method |
| CN113010969A (en) * | 2021-05-11 | 2021-06-22 | 中国空气动力研究与发展中心计算空气动力研究所 | Calculation and correction method for maximum value of pressure wave of high-speed train entering tunnel |
| CN114791330A (en) * | 2022-06-20 | 2022-07-26 | 中国空气动力研究与发展中心低速空气动力研究所 | Multichannel pressure scanning valve system |
| CN117147093B (en) * | 2023-10-30 | 2024-01-23 | 中国航空工业集团公司沈阳空气动力研究所 | Wind tunnel test measuring device for acoustic explosion characteristics of low acoustic explosion supersonic civil aircraft |
| CN117147092B (en) * | 2023-10-30 | 2024-01-23 | 中国航空工业集团公司沈阳空气动力研究所 | Ultrasonic static pressure probe-based acoustic explosion near-field space pressure measurement device |
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