CN114323071A - Heating life test device and method for vane sensor - Google Patents
Heating life test device and method for vane sensor Download PDFInfo
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Abstract
The invention belongs to the technical field of high-precision low-speed wind tunnels, and relates to a heating life test device and method for a vane sensor. Comprises a reducing wind pipe section, a test section, a gradually expanding wind pipe section and an electric control part. The high-precision low-speed weathervane sensor heating life test device can be used for a weathervane sensor heating life test and can be used for a performance test of a probe sensor and a meteorological wind speed sensor. Compared with similar equipment, the testing device has the advantages of small occupied area, low power consumption, low noise, high reliability and intellectualization. By way of example implementation, the use effect completely achieves the technical target determined in the early stage of the project.
Description
Technical Field
The invention belongs to the technical field of high-precision low-speed wind tunnels, and relates to a heating life test device and method for a vane sensor.
Background
When the vane sensor is used as an airplane to fly, the vane sensor is used for detecting the local sideslip angle of the airplane in the air, and the flying safety of the airplane is guaranteed. At present, in the life test of the wind vane sensor, various test environments are tried, such as various methods of adjusting the blowing rate, modifying the parameters of the airflow flow field and the like, which can not reach the heating life test conditions of the wind vane sensor, so that the tested product often has burning failure, great economic loss is caused, and the delivery progress of the product is seriously influenced.
In order to accurately simulate the environmental conditions (the main index is expressed as airspeed) of the takeoff stage of an airplane, a test device with high wind speed, low cost, small volume and low noise is urgently needed to be designed. And can be used for the performance test of other parts of vane type sensors, probe type sensors and wind speed sensors.
The new test device not only needs to meet the airspeed required by the service life test of the vane type sensor, but also has strict requirements on floor space, equipment manufacturing cost, use cost and reliability. The requirement for electricity consumption is particularly strict because the life test time is as long as one or two years, and a 24-hour continuous test is required, and once a fault (a test device or a tested product) occurs, the life test starting time must be calculated from the beginning, so that the delivery schedule of the product is greatly influenced.
The new test device adopts a brand-new air channel design method and is assisted by an advanced and reliable control circuit to control and adjust various parameters of the whole system. Through the verification of the use example, various parameters and reliability can meet the test requirement. Because the test section air duct of the test device is designed in a replaceable mode, the function expansion in a large range can be carried out.
Wind tunnel products at home and abroad are many, but the wind tunnel product has small occupied area and low cost, and is a blank product combined with a weather vane type service life test.
Disclosure of Invention
In view of the above-mentioned situation of the prior art, the present invention aims to provide a heating life test device for a vane sensor, and a safer and more advanced heating life test method for vane sensors.
The above object of the present invention is achieved by the following technical solutions:
a heating life test device for a wind vane sensor comprises a gradually-reducing wind pipe section, a test section, a gradually-expanding wind pipe section and an electrical control part. The electric control part comprises a plurality of sensors, an electronic instrument, a PLC, a touch screen and a low-voltage apparatus. The convergent wind pipe section and the divergent wind pipe section are wind tunnel types designed according to the Shore formula and the Vickers formula after the contraction ratio is determined; the wind quantity kinetic energy is selected from a high-rotating-speed direct current motor and is arranged in the gradually-expanding wind pipe section. And the air pressure differential pressure sensor senses the differential pressure between the convergent air pipe section and the divergent air pipe section, and inputs the differential pressure to a subsequent electronic instrument for resolving to obtain the air speed of the test section. The front of the contraction section adopts low-speed flow with large sectional area. The low-voltage control part can receive a control signal sent by the PLC, and automatically controls the starting and stopping of the fan and the on-off of the medium-frequency power supply through a control circuit consisting of the contactor, the thermal relay and the intermediate relay.
Wherein the rated wind speed is 50m/s, and the precision can reach 0.1 percent of the reading value.
Wherein the voltage level of the heating power supply is 115Vac/400 Hz.
In the PLC program, a high-precision timer is programmed, the timing precision can reach 0.01s, and the heating time of the vane type sensor can be accurately timed.
Furthermore, in order to facilitate observation of the working state of the tested wind vane sensor during the heating life test, the material of the test section should have a transparent characteristic.
Further, in order to further improve the measurement accuracy of the wind speed, the wind speed is corrected by using variables such as the ambient temperature and the ambient humidity during the calculation of the wind speed.
The structural design of the test section should satisfy the installation requirement of the product to be measured, namely in the test section cross-sectional dimension, at least one dimension should be greater than 92 mm.
A test method for the heating life of a vane sensor,
a differential pressure taking port is arranged between the wind tunnel reducing pipe and the wind tunnel expanding pipe, the differential pressure is introduced into an electronic instrument with a single chip microcomputer, and the electronic instrument is simultaneously provided with an environment temperature and humidity sensor for detecting the environment temperature and humidity at the current time and in the local place.
The electronic instrument calculates the theoretical wind speed according to the following formula under the standard climatic conditions (21 ℃, 29.92in Hg), and then corrects according to the real-time air temperature and humidity detected by the instrument, so that the wind speed precision of the wind tunnel can be improved.
Pd＝1/2ρ×V2
Wherein, Pd-differential pressure; ρ -air density; v-airspeed
The air pressure correction is calculated according to the following formula
Wherein,
BPa — actual air pressure; BPs-standard air pressure; ALT-sea level height; t-temperature
The electronic instrument corrects the theoretical airspeed into the indicated airspeed after resolving the theoretical airspeed. The accuracy can reach 0.1% rdg.
The invention has the advantages and beneficial effects that:
the high-precision low-speed weathervane sensor heating life test device can be used for a weathervane sensor heating life test and can be used for a performance test of a probe sensor and a meteorological wind speed sensor.
Compared with similar equipment, the testing device has the advantages of small occupied area, low power consumption, low noise, high reliability and intellectualization.
By way of example implementation, the use effect completely achieves the technical target determined in the early stage of the project.
Drawings
FIG. 1 is a block diagram of a heating life test device for a vane sensor according to the present invention;
FIG. 2 is an outline view of the heating life test device of the vane sensor of the present invention.
Detailed Description
The present invention will be further described with reference to the following examples. The following description is only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
A heating life test device for a wind vane sensor comprises a gradually-reducing wind pipe section, a test section, a gradually-expanding wind pipe section and an electrical control part. The electric control part comprises a plurality of sensors, an electronic instrument, a PLC, a touch screen and a low-voltage apparatus.
After the contraction ratio is determined, a brand new wind tunnel type is designed according to the Shore formula and the Vickers formula based on the principle of small occupied area and high efficiency; meanwhile, in order to reduce the cost, the wind kinetic energy is selected from a high-speed direct current motor and is arranged in the gradually expanding wind pipe section. The structure of the device is schematically shown in figure 2.
The structural design of the test section meets the installation requirements of the tested product, namely at least one of the section sizes of the test section is larger than 92 mm. And in order to facilitate observation of the working state of the tested wind vane sensor during the heating life test, the material of the test section should have the transparent characteristic.
The air pressure differential pressure sensor senses the differential pressure between the convergent air pipe section and the divergent air pipe section, and inputs the differential pressure to a subsequent electronic instrument for calculation to obtain the air speed of the test section. In order to further improve the measurement accuracy of the wind speed, the wind speed is corrected by variables such as the ambient temperature and the ambient humidity during calculation.
The front of the contraction section adopts large-section-area low-speed flow, so that the speed, pressure and power loss of front-section fluid can be greatly reduced, and the transmission power and noise of the fluid are reduced.
This structural design except can increasing test section air current kinetic energy and reducing fan motor power consumption, still can make the wind speed in the test section even, reduces the torrent.
Wherein the rated wind speed is 50m/s, and the precision can reach 0.1 percent of the reading value.
Wherein the voltage level of the heating power supply is 115Vac/400 Hz. The voltage level is the actual working voltage when the tested product is heated.
The PLC program can realize the control, regulation and protection of the whole equipment. When faults such as overheating of a fan, failure of a vane type sensor and the like occur in the system, heating is automatically stopped, and an alarm signal is sent out.
In the PLC program, a high-precision timer is programmed, the timing precision can reach 0.01s, and the heating time of the vane type sensor can be accurately timed.
In the PLC program, parameters such as wind speed, air pressure, environment temperature and humidity are automatically converted into engineering quantity signals, and operation of operators is facilitated.
In the PLC program, the PID regulating program can collect the wind speed and the current of the measured product, so that the heating current of the product is kept constant.
The touch screen program is provided with buttons for starting and stopping a fan, historical inquiry of alarm information and the like, and simultaneously displays parameters such as wind speed of a wind tunnel, environment temperature and humidity, pressure difference, accumulated heating time, heating current of a measured product and the like.
The low-voltage control part can receive a control signal sent by the PLC, and automatically controls the starting and stopping of the fan, the on-off of the medium-frequency power supply and the like through a control circuit consisting of low-voltage electric appliances such as a contactor, a thermal relay, an intermediate relay and the like.
The method comprises the following steps:
a differential pressure taking port is arranged between the wind tunnel reducing pipe and the wind tunnel expanding pipe, the differential pressure is introduced into an electronic instrument with a single chip microcomputer, and the electronic instrument is simultaneously provided with an environment temperature and humidity sensor for detecting the environment temperature and humidity at the current time and in the local place.
The electronic instrument calculates the theoretical wind speed according to the following formula under the standard climatic conditions (21 ℃, 29.92in Hg), and then corrects according to the real-time air temperature and humidity detected by the instrument, so that the wind speed precision of the wind tunnel can be improved.
Pd＝1/2ρ×V2
Wherein, Pd-differential pressure; ρ -air density; v-airspeed
The air pressure correction is calculated according to the following formula
Wherein,
BPa — actual air pressure; BPs-standard air pressure; ALT-sea level height; t-temperature (Jinlan temperature scale)
The electronic instrument corrects the theoretical airspeed into the indicated airspeed after resolving the theoretical airspeed. The accuracy can reach 0.1% rdg.
The heating current of the vane sensor is 2-3A, the voltage grade is 115Vac/400Hz, and a medium-frequency power supply with the rated power of 5KVA can be selected.
The method adopts a medium-frequency power supply current transmitter to detect the heating current of the vane sensor, and when the heating current exceeds 3+3 multiplied by 10%, an alarm signal is sent out, and meanwhile, the heating power supply is automatically cut off to protect the vane sensor.
The on-off of the medium-frequency power supply is controlled by a contactor, and an auxiliary contact of the contactor can be used as a time scale for heating time.
The power-off memory function can be realized by utilizing the timer with the power-off keeping function in the PLC.
The wind tunnel fan is controlled by the PLC to be switched on and off, and the rotating speed of the direct current motor can be adjusted through the special motor controller to form different wind speeds so as to meet the test requirements of the vane/probe type sensors with different requirements.
The PLC collects real-time wind speed and heating current, and according to the PID adjusting principle, the heating current is synchronously and automatically reduced after the wind speed is reduced for various reasons, so that the test safety of a tested product is ensured. And the surface temperature of the tested product is kept within the range required by the product, once the standard temperature is exceeded, the tested product outputs an alarm signal, the PLC immediately stops heating automatically after collecting the alarm signal, and the fan is stopped in a delayed manner.
The wind tunnel reducer and the wind tunnel expander are made of glass tubes with the thickness of 2.5mm, the middle test section is made of an acrylic transparent plate with the thickness of 3mm, and a hole is formed in one vertical surface according to the installation size of the wind vane sensor. And the vertical surface is a movable plate which can be fixed by screws, and the movable plate can be used for testing the pneumatic characteristics or other purposes of different vane/probe sensors by replacing the movable plate, so that the application range of the test device is expanded.
The wind tunnel is integrated and arranged above the frame of the testing device.
The touch screen, the PLC, the motor controller, the electronic instrument, the low-voltage apparatus and the like are installed in an independent control box, the space at the lower part of a rack of the testing device is fully utilized, a structural member of the rack is used as a supporting bracket of a control part, and an electric control box is formed by adding skin.
The structure can enable the whole testing device to be a whole, and the occupied area is reduced.
It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein. The above-mentioned embodiments, objects, technical solutions and advantages of the present invention are further described in detail, it should be understood that the above-mentioned embodiments are only illustrative of the present invention and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. A heating life test device for a wind vane sensor is characterized by comprising a gradually-reducing wind pipe section, a test section, a gradually-expanding wind pipe section and an electric control part; the electric control part comprises a plurality of sensors, an electronic instrument, a PLC, a touch screen and a low-voltage apparatus; the convergent wind pipe section and the divergent wind pipe section are wind tunnel types designed according to the Shore formula and the Vickers formula after the contraction ratio is determined; the wind quantity kinetic energy is selected from a high-rotating-speed direct current motor and is arranged in the gradually-expanded wind pipe section; the air pressure differential pressure sensor senses the differential pressure between the convergent air pipe section and the divergent air pipe section, and inputs the differential pressure to a subsequent electronic instrument for resolving to obtain the air speed of the test section; the front of the contraction section adopts large-section-area low-speed flow; the low-voltage control part can receive a control signal sent by the PLC, and automatically controls the starting and stopping of the fan and the on-off of the medium-frequency power supply through a control circuit consisting of the contactor, the thermal relay and the intermediate relay.
2. The weathercock sensor heating life test device of claim, wherein the rated wind speed is 50m/s, and the accuracy can reach 0.1% of the reading value.
3. The weathervane sensor heating life test device according to, wherein the voltage level of the heating power supply is 115Vac/400 Hz.
4. The weathercock sensor heating life test device of claim, wherein a high precision timer is programmed in the PLC program, the timing precision can reach 0.01s, and the heating time of the weathercock sensor can be accurately timed.
5. The weathervane sensor heating life test device of, wherein the material of the test section is transparent.
6. The weathervane sensor heating life test device according to the claim, wherein when wind speed is calculated, the ambient temperature and the ambient humidity are used for correction.
7. The weathervane sensor heating life test device of claim, wherein the test section is designed to meet the installation requirements of the tested product, i.e., at least one of the cross-sectional dimensions of the test section is greater than 92 mm.
8. A test method for the heating life of a vane sensor is characterized in that,
a differential pressure taking port is arranged between the wind tunnel reducing pipe and the wind tunnel expanding pipe, the differential pressure is introduced into an electronic instrument with a single chip microcomputer, and the electronic instrument is simultaneously provided with an environment temperature and humidity sensor for detecting the environment temperature and humidity at the current time and in the local place;
the electronic instrument calculates the theoretical wind speed according to the following formula under the standard climatic condition, and then corrects the theoretical wind speed according to the real-time air temperature and humidity detected by the instrument, so that the wind speed precision of the wind tunnel can be improved;
Pd＝1/2ρ×V2
wherein, Pd-differential pressure; ρ -air density; v-airspeed
The air pressure correction is calculated according to the following formula
Wherein,
BPa — actual air pressure; BPs-standard air pressure; ALT-sea level height; t-temperature
After resolving the theoretical airspeed, the electronic instrument corrects the theoretical airspeed into an indicated airspeed; the accuracy can reach 0.1% rdg.
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