CN102426091A - Protective device of dynamic pressure sensor used in wind tunnel air inlet experiment - Google Patents
Protective device of dynamic pressure sensor used in wind tunnel air inlet experiment Download PDFInfo
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- CN102426091A CN102426091A CN2011103104329A CN201110310432A CN102426091A CN 102426091 A CN102426091 A CN 102426091A CN 2011103104329 A CN2011103104329 A CN 2011103104329A CN 201110310432 A CN201110310432 A CN 201110310432A CN 102426091 A CN102426091 A CN 102426091A
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- dynamic pressure
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- air intake
- intake duct
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Abstract
The invention discloses a protective device of a dynamic pressure sensor used in a wind tunnel air inlet experiment. A pressure monitoring sensor monitors a dynamic pressure airflow change rate in an air inlet. After an amplified pressure airflow change rate signal exceeds a set parameter, an air inlet power supply is turned off. N dynamic pressure sensors collect dynamic pressure data of the air inlet. The data is amplified and is sent to an industrial controller through a VXI data acquisition system so as to obtain a distortion index needed by the air inlet experiment. A vibration monitoring sensor measures dynamic airflow vibration change in the air inlet. After the amplified dynamic airflow vibration signal exceeds the set parameter, the air inlet power supply is turned off. By using the protective device of the invention, the dynamic pressure sensor can be protected so that economic losses can be reduced. Folding installation can be achieved and usage is convenient.
Description
Technical field
The present invention relates to the survey control technology field, especially a kind of protective device of pressure transducer.
Background technology
The experiment of wind-tunnel air intake duct is accomplished the measurement to distortion index with dynamic pressure transducer.Because the technology of manufacturing dynamic pressure transducer is difficulty and cost height very, the dynamic pressure transducer price is very expensive.Like " dynamic pressure distortion HSDA and real-time storage disposal system " is the crucial analysis of experiments device of sill that the air inlet compatibility is estimated; Thought a kind of technical sophistication, the system that involves great expense abroad; U.S. FAT company once offered 3,000,000 dollars, and wherein the dynamic pressure transducer proportion is very big.Its unit price of difference unit from thousands of to tens thousand of according to indexs such as the measuring accuracy of dynamic pressure transducer, range, frequency response, quality does not wait.The measurement of inlet distortion index is tested at every turn need be with the dynamic pressure transducer more than 10, and the quality of the dynamic pressure data that measure can directly influence experimental result, so dynamic pressure transducer is most important.When testing, general air intake duct need select the range and the precision of dynamic pressure transducer as requested.The too big measuring accuracy of measurement range selection does not reach and requires data inaccurate, and selected range is moderate can effectively to obtain to measure dynamic data but the very easy dynamic pressure transducer that damages, and damages the back replacing and bothers very much again.Studying carefully its reason of damaging easily is when carrying out the air intake duct experiment because of wind-tunnel; In the air intake duct dynamic pressure is arranged not only but also have dynamic vibration and dynamic impulsion; Air-flow is very complicated; The flow field is extremely unstable, has caused the damage of dynamic pressure transducer, and it is bigger wherein to vibrate and impact the factor that causes.Technology does not have good way to come effectively protection dynamic pressure transducer now.With experiment experience and experimental data parameters such as transducer range and precision are selected to avoid the damage of dynamic pressure transducer exactly air intake duct.Since the price of dynamic pressure transducer very costliness again to measuring quality and experimental data decisive role.Extremely important to the protection of dynamic pressure transducer like this with regard to what show.For this reason " vibration with impact " published " application of depression bar strain pressure transducer in the explosion wave load test " literary composition in April, 2007 and relate to and use the depression bar strain pressure transducer to solve problems such as the low and easy damage of common sensor frequency response under the high-frequency pressure pulse.This method ultimate principle can not be used for the experiment of wind-tunnel air intake duct, in addition, because the protector volume can't be installed in the air intake duct greatly." oil gas accumulating " 01 periodical in 1999 is stepped on " dynamic perfromance of Shuttle-type Rupturing Protection Valve of Pipeline "; Shuttle-type Rupturing Protection Valve of Pipeline is used for when pipe leakage reaches the protection value of setting, can block rapidly to carry to prevent to leak and just dynamic perfromance carried out experimental study.More than two kinds of methods can not be applied in the experiment of wind-tunnel air intake duct and effectively protect dynamic pressure transducer and prevent and damage.
Summary of the invention
In order to overcome the deficiency that prior art can't be protected dynamic pressure transducer and prevent to damage in the experiment of wind-tunnel air intake duct; The present invention provides a kind of wind-tunnel air intake duct experiment dynamic pressure transducer protective device; According to the dynamic pickup instructions parameter and the experiment experience that the pressure monitoring parameter is provided with device is set the parameter that the vibration monitoring parameter is provided with device is set; Force value in air intake duct or vibration values overpressure monitoring parameter are provided with the parameter value rear drive stop that device or vibration monitoring parameter be provided with the device setting and cut off the air intake duct power supply rapidly, thereby effectively protect dynamic pressure transducer.
Main thought of the present invention is: dynamic pressure transducer, PVDF pressure transducer and PVDF vibration transducer can be used for measuring the variation of interior dynamic pressure of air intake duct and vibration.Table 1 is the various performance comparison of dynamic pressure transducer, PVDF pressure transducer, PVDF vibration transducer, obtains conclusion thus; 1, because the PVDF material sensors is fast to the jump signal reaction, can reflect the rate of change of air-flow in the air intake duct in advance.2, the PVDF material sensors have highly sensitive, very frivolous, shock-resistant, Hz-KHz is wide, cost is low, non-damageable characteristics.3, because measurement dynamic range and frequency range are big, PVDF need not change the range of pressure monitoring sensor and vibration transducer.4, dynamic pressure transducer is measured the precision height; Can be used for measurement data; And that PVDF pressure transducer, PVDF vibration transducer are measured precision is low; Can be used to protect pressure transducer, according to the instructions of dynamic pickup the content of parameter that the pressure monitoring parameter is provided with device (dynamic pressure maximal value, dynamic pressure maximal value time delay, frequency response) is set and puts into the pressure monitoring parameter as parameter value device is set.According to experiment experience parameter that the vibration monitoring parameter is provided with device being set obtains content of parameter (maximum vibration frequency, maximum vibration frequency time delay, vibration displacement) and puts into the vibration monitoring parameter as parameter value device is set.After parameter or dynamic vibration parameter that the pressure overpressure monitoring parameter in the air intake duct is provided with device surpassed the vibration monitoring parameter parameter of device is set, pressure stop or vibration stop cut off air intake duct rapidly
Table 1
Power supply, dynamic pressure transducer is played a protective role.
The technical scheme that technical solution problem of the present invention is adopted is: comprise that pressure monitoring sensor, charge amplifier, pressure monitoring parameter are provided with device, pressure stop, a N dynamic pressure transducer, a N programmable amplifier, VXI data acquisition system (DAS), Industrial Control Computer, air intake duct power supply, vibration monitoring sensor, isolated amplifier, vibration monitoring parameter device and vibration stop, 1 ≤N ≤300 are set.Dynamic pressure variations in flow rate in the pressure monitoring sensor monitors air intake duct; Output pressure variations in flow rate signal to charge amplifier amplifies; Forced draft rate of change signal overpressure monitoring parameter after amplifying turn-offs the air intake duct power supply by the pressure stop after the parameter that device is provided with is set; N dynamic pressure transducer gathered the dynamic pressure data of air intake duct; Transfer to the VXI data acquisition system (DAS) after amplifying through N programmable amplifier respectively; The VXI data acquisition system (DAS) is gathered the dynamic pressure data and is sent into Industrial Control Computer again and obtain air intake duct and test needed distortion index through calculating the distortion index method; The dynamic air current vibration changes in the vibration monitoring sensor measurement air intake duct, and output dynamic air current vibration signal amplifies to isolated amplifier, and the dynamic air current vibration signal after amplifying surpasses and turn-offs the air intake duct power supply by the vibration stop after the vibration monitoring parameter is provided with the parameter that device is provided with; Industrial Control Computer is provided with the parameter that the pressure monitoring parameter is provided with device according to the dynamic pressure transducer range in the dynamic pressure transducer instructions, according to the actual demand of testing the parameter that the vibration monitoring parameter is provided with device is set.
Described pressure monitoring sensor adopts the PVDF material pressure transducer.
Described vibration monitoring sensor adopts PVDF material vibrating sensor.
Described pressure monitoring sensor, dynamic pressure transducer and vibration monitoring sensor are installed on the same xsect of air intake duct, and evenly distribute by circumferencial direction, connect the earth after above-mentioned three kinds of sensor mask.
Described pressure monitoring parameter is provided with the content of parameter of device and follows following requirement by dynamic pressure transducer instructions:
1, dynamic pressure maximal value ≤dynamic pressure transducer pressure range * 1.414.
2, dynamic pressure maximal value ≤0.1 S ~ 0.5S time delay.
3, frequency response ≤1/2 ~ 1/10* dynamic pressure transducer natural frequency.
Three parameter values are put into the pressure monitoring parameter device is set, turn-off the air intake duct power supply later on when the parameter in air intake duct surpasses setting value.
The content of parameter that described vibration monitoring parameter is provided with device is followed experiment experience by following requirement:
1, the maximum vibration frequency is got 0.5 Hz ~ 7Hz.
2, maximum vibration frequency ≤0.3S ~ 1S time delay.
3, vibration displacement ≤400 um ~ 1000um.
Three parameter values are put into the vibration monitoring parameter device is set, turn-off the air intake duct power supply later on when the parameter in air intake duct surpasses setting value.
The invention has the beneficial effects as follows: the present invention can provide the device of protection dynamic pressure transducer; Force value in air intake duct or vibration values overpressure monitoring parameter are provided with the parameter value rear drive stop that device or vibration monitoring parameter be provided with the device setting and cut off the air intake duct power supply rapidly, thereby the effect of playing the protection dynamic pressure transducer reduces economic loss.The cost of material is low to utilize PVDF, but collapsible installation, the convenient characteristics of using also various pressure experiments of widespread use or vibration experiment.
Below in conjunction with accompanying drawing and embodiment the present invention is further specified.
Description of drawings
Fig. 1 is a device synoptic diagram of the present invention.
Embodiment
Fig. 1 is a device synoptic diagram of the present invention; Dynamic pressure variations in flow rate is that the charge amplifier of M193802 amplifies the dynamic air current pressure change rate to model in the pressure monitoring sensor monitors air intake duct, and it be that the pressure monitoring parameter of YPK-38 is provided with after the parameter of device by model is that the pressure stop of LSM 020.2 turn-offs the air intake duct power supply that the signal after amplifying surpasses model.Choose N=15, the dynamic pressure transducer 1 that to adopt 15 models are XCS-9301-5D ..., dynamic pressure transducer 15 gather air intake ducts dynamic data respectively through through model be the TS-2000 plate multichannel programmable amplifier 1 ..., programmable amplifier 15 with dynamic data amplify the back to model be the VXI data acquisition system (DAS) parallel acquisition dynamic data of VXI16015S.It is that the Industrial Control Computer of IPC610 calculates the needed distortion index of air intake duct experimental result that the VXI data acquisition system (DAS) is sent dynamic data into model.The dynamic air current vibration signal is that the isolated amplifier of AD204 amplifies vibration signal through model in the vibration monitoring sensor measurement air intake duct, and it be that the vibration monitoring parameter of JYHK-HZD-B-5 is provided with after the parameter of device setting by model is that the vibration stop of G37 turn-offs the air intake duct power supply that the signal after amplifying surpasses model.According to the dynamic pressure transducer range in the dynamic pressure transducer instructions parameter that the pressure monitoring parameter is provided with device is set with the Industrial Control Computer Industrial Control Computer, Industrial Control Computer is provided with the parameter that the vibration monitoring parameter is provided with device according to experiment experience.
The material of selecting the pressure monitoring sensor for use is the PVDF material pressure transducer, and its size is Φ 50mm, thick 350 μ m.
The material of selecting the vibration monitoring sensor for use is a PVDF material vibrating sensor, and size is: long 18mm, wide 18mm, thick 170 μ m.
Select for use a pressure monitoring sensor, 15 dynamic pressure transducers, vibration monitoring sensor to be installed on the xsect of Φ 350mm and evenly distribute, again with connecting the earth after the sensor mask by circumferencial direction.
The dynamic pressure transducer range is provided with the content of parameter that the pressure monitoring parameter is provided with device:
When the range of dynamic pressure transducer=5PSI;
1, dynamic pressure maximal value=7PSI.
2, dynamic pressure maximal value time delay=0.1S.
3, frequency response=100KHZ.
Three parameter values are put into the pressure monitoring parameter device is set, turn-off the air intake duct power supply later on when the parameter in air intake duct surpasses setting value.
The content of parameter that the vibration monitoring parameter is provided with device is set:
1, the maximum vibration frequency is got 0.5HZ.
2, maximum vibration frequency time delay=0.3S.
3, vibration displacement=400um.
Three parameter values are put into the vibration monitoring parameter device is set, turn-off the air intake duct power supply later on when the parameter in air intake duct surpasses setting value.
Explain: when the range of dynamic pressure transducer=can get the higher limit that is provided with in the parameter during 100PSI.Work as 100PSI>range >=10PSI can get the intermediate value that is provided with in the parameter, work as 10PSI>range can get the lower limit that is provided with in the parameter (parameter is set comprises that the pressure monitoring parameter is provided with three parameter values of device and three parameter values that the vibration monitoring parameter is provided with device).
When above-mentioned parameter N is set to numbers such as 1,90,300, only the density that distributes etc. is changed and get final product, all can realize same function, number is many more, measurement accurate more.
The present invention compared with prior art has following significant advantage:
1), when occurring ultra dynamic dynamic pressure maximal value, dynamic pressure maximal value time delay, frequency response and maximum vibration frequency, maximum vibration frequency time delay, vibration displacement in the air intake duct, in time cuts off the electricity supply dynamic pressure transducer is effectively protected because the pressure monitoring sensor is fast to dynamic pressure variations in flow rate reaction.
2) because PVDF measures the dynamic pressure range and vibration frequency range is big, price quite cheaply and not can be damaged, so need not change pressure monitoring sensor and vibration transducer.
3) in experiment, can select the high-acruracy survey of carrying out distortion index near the dynamic pressure transducer of maximum data range for use as far as possible, make measurement data more near actual conditions.
4) the cost of material is low for PVDF, collapsible installing and using.
Working routine is: 1, install: with pressure monitoring sensor, dynamic pressure transducer 1 ... Dynamic pressure transducer N, vibration monitoring sensor are installed on the xsect and evenly distribute by circumferencial direction, again with connecting the earth after the sensor mask.2, with Industrial Control Computer the pressure monitoring parameter being set respectively is provided with the parameter of device and the parameter that the vibration monitoring parameter is provided with device is set; According to the instructions of dynamic pickup the parameter that the pressure monitoring parameter is provided with device (dynamic pressure maximal value, dynamic pressure maximal value time delay, frequency response) is set, the parameter that the vibration monitoring parameter is provided with device (maximum vibration frequency, maximum vibration frequency time delay, vibration displacement) is set according to experiment experience.3, experiment: the dynamic pressure air-flow of air intake duct is increased; Dynamic pressure variations in flow rate to charge amplifier amplifies the dynamic air current pressure change rate in the pressure monitoring sensor monitors air intake duct, and the pressure change rate signal overpressure monitoring parameter after amplifying automatically shuts down the air intake duct power supply by the pressure stop after the parameter of device setting is set.The dynamic air current vibration signal changes and through isolated amplifier vibration signal is amplified in the vibration monitoring sensor measurement air intake duct, and the dynamic air current vibration signal after amplifying surpasses and turn-offs the air intake duct power supply by the vibration stop after the vibration monitoring parameter is provided with the parameter that device is provided with.4, the course of work: start the air intake duct power supply, dynamic pressure transducer measures the interior dynamic pressure signal of wind-tunnel air intake duct and obtains effective dynamic measuring data through programmable amplifier, VXI data acquisition system (DAS).The dynamic pressure signal that dynamic pressure in the pressure monitoring sensor monitors air intake duct obtains is through amplifying signal through charge amplifier, and the signal overpressure monitoring parameter after amplifying automatically shuts down the air intake duct power supply by the pressure stop after the parameter of device setting is set.The dynamic air current vibration signal changes and through isolated amplifier vibration signal is amplified in the vibration monitoring sensor measurement air intake duct, and the signal after amplifying surpasses and turn-offs the air intake duct power supply by the vibration stop after the vibration monitoring parameter is provided with the parameter that device is provided with.Dynamic pressure transducer is played a protective role.
Claims (6)
1. a wind-tunnel air intake duct is tested the dynamic pressure transducer protective device; Comprise that pressure monitoring sensor, charge amplifier, pressure monitoring parameter are provided with device, pressure stop, a N dynamic pressure transducer, a N programmable amplifier, VXI data acquisition system (DAS), Industrial Control Computer, air intake duct power supply, vibration monitoring sensor, isolated amplifier, vibration monitoring parameter device and vibration stop are set, it is characterized in that: 1 ≤N ≤300; Dynamic pressure variations in flow rate in the pressure monitoring sensor monitors air intake duct; Output pressure variations in flow rate signal to charge amplifier amplifies; Forced draft rate of change signal overpressure monitoring parameter after amplifying turn-offs the air intake duct power supply by the pressure stop after the parameter that device is provided with is set; N dynamic pressure transducer gathered the dynamic pressure data of air intake duct; Transfer to the VXI data acquisition system (DAS) after amplifying through N programmable amplifier respectively; The VXI data acquisition system (DAS) is gathered the dynamic pressure data and is sent into Industrial Control Computer again and obtain air intake duct and test needed distortion index through calculating the distortion index method; The dynamic air current vibration changes in the vibration monitoring sensor measurement air intake duct; Output dynamic air current vibration signal to isolated amplifier amplifies, and the dynamic air current vibration signal after amplifying surpasses and turn-offs the air intake duct power supply by the vibration stop after the vibration monitoring parameter is provided with the parameter that device is provided with, and Industrial Control Computer is provided with the pressure monitoring parameter parameter that device and vibration monitoring parameter are provided with device is set.
2. according to utilizing profit to require 1 described wind-tunnel air intake duct experiment dynamic pressure transducer protective device, it is characterized in that: described pressure monitoring sensor adopts the PVDF material pressure transducer.
3. according to utilizing profit to require 1 described wind-tunnel air intake duct experiment dynamic pressure transducer protective device, it is characterized in that: described vibration monitoring sensor adopts PVDF material vibrating sensor.
4. according to utilizing profit to require 1 described wind-tunnel air intake duct experiment dynamic pressure transducer protective device; It is characterized in that: described pressure monitoring sensor, dynamic pressure transducer and vibration monitoring sensor are installed on the same xsect of air intake duct; And evenly distribute by circumferencial direction, connect the earth after above-mentioned three kinds of sensor mask.
5. according to utilizing profit to require 1 described wind-tunnel air intake duct experiment dynamic pressure transducer protective device; It is characterized in that: described pressure monitoring parameter is provided with dynamic pressure the maximal value ≤dynamic pressure transducer pressure range * 1.414 of device; Dynamic pressure maximal value time delay ≤0.1 S ~ 0.5S, frequency response ≤1/2 ~ 1/10* dynamic pressure transducer natural frequency.
6. according to utilizing profit to require 1 described wind-tunnel air intake duct experiment dynamic pressure transducer protective device; It is characterized in that: described maximum vibration frequency is got 0.5 Hz ~ 7Hz; Maximum vibration frequency time delay ≤0.3S ~ 1S, vibration displacement ≤400 um ~ 1000um.
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| CN 201110310432 CN102426091B (en) | 2011-10-13 | 2011-10-13 | Protective device of dynamic pressure sensor used in wind tunnel air inlet experiment |
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| CN 201110310432 CN102426091B (en) | 2011-10-13 | 2011-10-13 | Protective device of dynamic pressure sensor used in wind tunnel air inlet experiment |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103234756A (en) * | 2013-04-16 | 2013-08-07 | 中国航空工业集团公司沈阳发动机设计研究所 | Net type distortion device for large-bypass-ratio engines |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103234756A (en) * | 2013-04-16 | 2013-08-07 | 中国航空工业集团公司沈阳发动机设计研究所 | Net type distortion device for large-bypass-ratio engines |
| CN103234756B (en) * | 2013-04-16 | 2015-09-30 | 中国航空工业集团公司沈阳发动机设计研究所 | A kind of large bypass ratio engine net formula distortion device |
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