CN114384955A - Low-temperature low-pressure relative humidity standard device - Google Patents
Low-temperature low-pressure relative humidity standard device Download PDFInfo
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- CN114384955A CN114384955A CN202111561869.XA CN202111561869A CN114384955A CN 114384955 A CN114384955 A CN 114384955A CN 202111561869 A CN202111561869 A CN 202111561869A CN 114384955 A CN114384955 A CN 114384955A
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05D—SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES
- G05D27/00—Simultaneous control of variables covered by two or more of main groups G05D1/00 - G05D25/00
- G05D27/02—Simultaneous control of variables covered by two or more of main groups G05D1/00 - G05D25/00 characterised by the use of electric means
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01W—METEOROLOGY
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- G01W1/08—Adaptations of balloons, missiles, or aircraft for meteorological purposes; Radiosondes
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Abstract
The invention discloses a low-temperature low-pressure relative humidity standard device, and belongs to the technical field of metering tests. The device comprises a low-temperature saturation system, a low-temperature low-pressure measuring chamber system, a constant-temperature system, a pressure measurement control system and a vacuum system. The air outlet of the low-temperature saturation system is connected with the air inlet of the pressure measurement control system, the air outlet of the pressure measurement control system is connected with the air inlet of the low-temperature low-pressure measurement chamber system, and the air outlet of the low-temperature low-pressure measurement chamber system is connected with the vacuum system. The low-temperature saturation system and the low-temperature low-pressure measuring chamber system are respectively arranged in two independent constant temperature systems. The humidity comprehensive calibration device is simple in structure and low in cost, can provide standard humidity of different humidity under the condition of low temperature and low pressure, and meets the humidity comprehensive calibration requirement of the sonde under the condition of low temperature and low pressure.
Description
Technical Field
The invention relates to a relative humidity measurement testing device, in particular to a low-temperature low-pressure relative humidity standard device, and belongs to the technical field of measurement testing.
Background
With the rapid development of high and new technologies such as aerospace, microelectronics, infrared remote sensing and the like in China, the requirement on high-altitude weather detection is higher and higher, and the weather detection tool which is most used at present is a sonde. The sonde is a comprehensive test instrument for testing the high altitude temperature, the relative humidity and the pressure, and the performance of the sonde directly influences the accuracy of weather forecast. In order to guarantee the accuracy and reliability of meteorological detection data of the sonde, the comprehensive calibration problem of humidity parameters of the sonde under the conditions of low temperature and low pressure needs to be solved urgently. The temperature, pressure and relative humidity ranges required for the calibration of the sonde are respectively as follows: the temperature range is minus 90 ℃ to plus 20 ℃, the pressure range is 10hPa to 1000hPa, and the relative humidity range is 10 percent to 95 percent.
Relative humidity standards are widely used metering equipment for calibrating and calibrating gas relative humidity measuring instruments. The existing relative humidity standard device can only generate standard gas with certain humidity under normal pressure, can not realize standard moisture under low pressure condition, and can not realize comprehensive calibration of relative humidity parameters under low temperature and low pressure. Some humidity standard devices can achieve humidity calibration at high pressure, but still cannot generate standard humidity of a certain humidity under low temperature and low pressure conditions.
Disclosure of Invention
The invention discloses a low-temperature low-pressure relative humidity standard device, aiming at solving the problem that the existing relative humidity standard device cannot be applied to a low-temperature low-pressure environment, and aiming at meeting the requirement of comprehensive calibration of humidity parameters under the condition of low temperature and low pressure.
The purpose of the invention is realized by the following technical scheme:
a low-temperature low-pressure relative humidity standard device comprises a low-temperature saturation system, a low-temperature low-pressure measuring chamber system, a constant temperature system, a pressure measurement control system and a vacuum system.
The air outlet of the low-temperature saturation system is connected with the air inlet of the pressure measurement control system, the air outlet of the pressure measurement control system is connected with the air inlet of the low-temperature low-pressure measurement chamber system, and the air outlet of the low-temperature low-pressure measurement chamber system is connected with the vacuum system.
The low-temperature saturation system and the low-temperature low-pressure measuring chamber system are respectively arranged in two independent constant temperature systems.
The gas pipelines among the low-temperature saturation system, the pressure measurement control system and the low-temperature low-pressure measurement chamber system are connected by a clamping sleeve joint or a vacuum connection radial seal (VCR) joint, and the low-temperature low-pressure measurement chamber system is connected with the vacuum system by a vacuum (KF) joint.
The low-temperature saturation system consists of a top cover, an upper condensation plate, an intermediate condensation plate, a lower condensation plate, a base plate, a gas path pipeline and a heat exchange coil. The top cover is made of non-metal heat insulation material, and the rest part is made of stainless steel material with polished inner wall. The top cover is positioned on the upper condensation plate, an inner condensation plate, a lower condensation plate and a chassis are sequentially arranged downwards, the upper and lower layers of condensation plates and the chassis are connected by staggered gas circuit pipelines, and heat exchange coil pipes are arranged outside the condensation plates and the chassis. The bottom of the chassis is provided with a water outlet.
The low-temperature and low-pressure measuring chamber system consists of a heat exchange coil, a measuring cavity, a sealing flange and a four-way interface. The measuring cavity is of a stainless steel hollow cylindrical structure with an inverted cone at the bottom, the top is sealed by a stainless steel sealing flange, and a stainless steel four-way vacuum joint is welded on the flange; and a central air outlet at the bottom of the measuring cavity is connected with the stainless steel heat exchange coil.
The pressure measurement control system consists of a mass flow controller, a high-precision pressure gauge, a vacuum gauge and a needle valve. The mass flow controller is positioned at an air inlet of the low-temperature saturation system, the high-precision pressure gauge is arranged at an air outlet of the low-temperature saturation system, the vacuum gauge is arranged at an air outlet of the low-temperature low-pressure measuring chamber system, and the needle valves are respectively positioned between the low-temperature saturation system and the low-temperature low-pressure measuring chamber system and at the outlet of the low-temperature low-pressure measuring chamber system and connected with the vacuum system.
The vacuum system comprises a vacuum pump, a filter and an air pumping pipeline.
The working mode of the device is as follows:
the device realizes saturated moisture under low temperature and normal pressure in a low temperature saturation system, and the saturated moisture under low temperature and normal pressure enters a low temperature and low pressure measuring chamber system through a gas pipeline to obtain standard gas with different humidity under low temperature and low pressure. The device realizes different low-temperature environments in a low-temperature saturation system and a low-temperature low-pressure measuring chamber system through a constant temperature system, and realizes the low-pressure environments in a normal-pressure low-pressure measuring chamber system and a low-temperature low-pressure measuring chamber system in the low-temperature saturation system under the combined action of a pressure measurement control system and a vacuum system. The device obtains standard gas with different humidity under certain temperature and pressure conditions by changing the temperature of the low-temperature saturation system, and can simultaneously carry out comprehensive calibration of temperature, pressure and relative humidity parameters.
Has the advantages that:
1. the humidity comprehensive calibration device is simple in structure and low in cost, can provide standard humidity of different humidity under the condition of low temperature and low pressure, and meets the humidity comprehensive calibration requirement of the sonde under the condition of low temperature and low pressure.
Drawings
FIG. 1 is a schematic diagram of a low temperature and low pressure relative humidity standard device according to the present invention;
FIG. 2 is a schematic structural diagram of a low-temperature and low-pressure measuring chamber system according to the present invention;
fig. 3 is a schematic structural diagram of a low-temperature saturation system according to the present invention.
Wherein the reference numbers:
1-low temperature saturation system, 2-low temperature and low pressure measuring chamber system, 3-constant temperature system, 4-constant temperature system, 5-pressure measuring control system, 6-vacuum system, 7-mass flow controller, 8-high precision pressure gauge, 9-needle valve, 10-vacuum gauge, 11-needle valve, 12-heat exchange coil, 13-measuring cavity, 14-sealing flange, 15-four-way interface, 16-top cover, 17-upper condensation plate, 18-inner condensation plate, 19-lower condensation plate, 20-bottom plate, 21-gas path pipeline, 22-heat exchange coil
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings and examples. The technical problems and the advantages solved by the technical solutions of the present invention are also described, and it should be noted that the described embodiments are only intended to facilitate the understanding of the present invention, and do not have any limiting effect.
The temperature, pressure and relative humidity ranges required for the calibration of the sonde are respectively as follows: the temperature range is minus 90 ℃ to plus 20 ℃, the pressure range is 10hPa to 1000hPa, and the relative humidity range is 10 percent to 95 percent. In order to meet the calibration requirement of the sonde, the low-temperature low-pressure humidity standard device of the embodiment comprises a low-temperature saturation system, a low-temperature low-pressure measuring chamber system, a constant-temperature system, a pressure measurement control system and a vacuum system.
The gas outlet of the low-temperature saturation system (1) is connected with the gas inlet of the pressure measurement control system (5), the gas outlet of the pressure measurement control system (5) is connected with the gas inlet of the low-temperature low-pressure measurement chamber system (2), and the gas outlet of the low-temperature low-pressure measurement chamber system (2) is connected with the vacuum system (6).
The low-temperature saturation system (1) is arranged in the constant-temperature system (3), and the low-temperature low-pressure measuring chamber system (2) is arranged in the constant-temperature system (4).
The gas pipelines between the low-temperature saturation system (1), the pressure measurement control system (5) and the low-temperature low-pressure measurement chamber system (2) are connected by VCR joints, and the low-temperature low-pressure measurement chamber system and the vacuum system are connected by vacuum (KF) joints.
The low-temperature saturation system (1) is composed of a top cover (16), an upper condensation plate (17), an intermediate condensation plate (18), a lower condensation plate (19), a base plate (20), a gas path pipeline (21) and a heat exchange coil (22). The top cover is made of non-metal heat insulating material, and the rest part is made of stainless steel material with polished inner wall. The top cover (16) is positioned on the upper condensation plate (17), an inner condensation plate (18), a lower condensation plate (19) and a base plate (20) are sequentially arranged downwards, 8 staggered air channel pipelines are adopted between the two layers of condensation plates and between the condensation plates and the base plate for connection, and the diameter of each pipeline is 12 mm. The height of the gas path pipeline extending into the upper layer condensation plate is 1/5-1/6 of disc height, and the height of the gas path pipeline extending into the lower layer condensation plate is 1/3-1/2 of disc height. The outside of the condensing disc and the chassis is provided with a heat exchange coil (22). The bottom (20) of the chassis is provided with a water outlet which extends into the chassis and has the height of 1/5 which is the height of the chassis.
The low-temperature and low-pressure measuring chamber system (2) is composed of a heat exchange coil (12), a measuring cavity (13), a sealing flange (14) and a four-way interface (15). The heat exchange coil (12), the measuring cavity (13), the sealing flange (14) and the four-way connector (15) are made of stainless steel with polished inner walls. The measuring cavity (13) is of a hollow cylindrical structure with an inverted cone at the bottom, and the cone angle is 45 degrees. The top of the device is sealed by a sealing flange (14), and a four-way connector (15) is welded on the sealing flange (14). An air outlet is arranged at the center of the bottom and is connected with the heat exchange coil (12).
The pressure measurement control system (5) is composed of a mass flow controller (7), a high-precision pressure gauge (8), a vacuum gauge (10) and needle valves (9) and (11). The mass flow controller (7) is positioned at an air inlet of the low-temperature saturation system (1), the high-precision pressure gauge (8) is arranged at the air outlet of the low-temperature saturation system (1), the vacuum gauge (10) is arranged at the air outlet of the low-temperature low-pressure measuring chamber system (2), the needle valve (9) is arranged between the low-temperature saturation system (1) and the low-temperature low-pressure measuring chamber system (2), and the needle valve (11) is positioned at an outlet of the low-temperature low-pressure measuring chamber system (2) and is connected with the vacuum system (6).
The vacuum system (6) comprises a vacuum pump, a filter and an air suction pipeline.
The low-temperature saturation system is used for realizing saturated moisture under low temperature and normal pressure, and the low-temperature and low-pressure measuring chamber system can provide standard moisture with specific humidity under the conditions of low temperature and low pressure for calibrating the humidity of the sonde under the conditions of low temperature and low pressure. The low-pressure measurement control system and the vacuum system are used for realizing different pressure environments in the low-temperature saturation system and the low-temperature low-pressure measurement chamber system.
The working mode of the device is as follows:
take the example of a low-temperature low-pressure relative humidity standard device generating standard moisture with the temperature of-90 ℃, the pressure of 10hPa and the relative humidity of 10%. After the low-temperature low-pressure relative humidity standard device sets the temperature, the pressure and the relative humidity value, the constant temperature system (3) automatically sets the temperature to be-76 ℃, the constant temperature system (4) automatically sets the temperature to be-90 ℃, gas output by a gas source enters the mass flow controller (7) through a pipeline and then enters the low-temperature saturation system (1) and the low-temperature low-pressure measuring chamber system (2), the flow of the required mass flow controller (7) is adjusted, the vacuum system (6) is started, needle valves (9) and (11) in the low-pressure measuring control system (5) are jointly adjusted, the pressure values of the low-temperature saturation system (1) and the low-temperature low-pressure measuring chamber system (2) are observed in real time, so that the pressure in the low-temperature saturation system (1) is maintained at normal pressure, namely, the high-precision pressure gauge (8) displays the atmospheric pressure, and the pressure in the low-temperature low-pressure measuring chamber system (2) is 10hPa, namely, the vacuum gauge (10) shows 10hPa, and when the pressure and the temperature in the low-temperature saturation system (1) and the low-temperature low-pressure measuring chamber system (2) of the low-temperature low-pressure relative humidity standard device are stabilized, the humidity value of the low-temperature low-pressure relative humidity standard device reaches a set value 10% RH.
The above detailed description is intended to illustrate the objects, aspects and advantages of the present invention, and it should be understood that the above detailed description is only exemplary of the present invention and is not intended to limit the scope of the present invention, and any modifications, equivalents, improvements and the like within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (7)
1. A low temperature low pressure relative humidity standard device which characterized in that: the system consists of a low-temperature saturation system, a low-temperature low-pressure measuring chamber system, a constant-temperature system, a pressure measurement control system and a vacuum system;
the air outlet of the low-temperature saturation system is connected with the air inlet of the pressure measurement control system, the air outlet of the pressure measurement control system is connected with the air inlet of the low-temperature low-pressure measurement chamber system, and the air outlet of the low-temperature low-pressure measurement chamber system is connected with the vacuum system;
the low-temperature saturation system and the low-temperature low-pressure measuring chamber system are respectively arranged in two independent constant temperature systems.
2. A low temperature low pressure relative humidity standard device as claimed in claim 1, wherein: the gas pipeline among the low-temperature saturation system, the pressure measurement control system and the low-temperature low-pressure measurement chamber system is connected by a clamping sleeve joint or a vacuum connection radial sealing joint, and the low-temperature low-pressure measurement chamber system is connected with the vacuum system by a vacuum joint.
3. A low temperature low pressure relative humidity standard device as claimed in claim 1 or 2, wherein: the low-temperature saturation system consists of a top cover, an upper condensation plate, an intermediate condensation plate, a lower condensation plate, a base plate, a gas path pipeline and a heat exchange coil; the top cover is made of a non-metal heat-insulating material, and the rest part is made of a stainless steel material with a polished inner wall; the top cover is positioned above the upper condensation plate, an inner condensation plate, a lower condensation plate and a chassis are sequentially arranged downwards, the upper and lower layers of condensation plates and the chassis are connected by staggered gas path pipelines, and heat exchange coil pipes are arranged outside the condensation plates and the chassis; the bottom of the chassis is provided with a water outlet.
4. A low temperature low pressure relative humidity standard device as claimed in claim 1 or 2, wherein: the low-temperature and low-pressure measuring chamber system consists of a heat exchange coil, a measuring cavity, a sealing flange and a four-way interface; the measuring cavity is of a stainless steel hollow cylindrical structure with an inverted cone at the bottom, the top is sealed by a stainless steel sealing flange, and a stainless steel four-way vacuum joint is welded on the flange; and a central air outlet at the bottom of the measuring cavity is connected with the stainless steel heat exchange coil.
5. A low temperature low pressure relative humidity standard device as claimed in claim 1 or 2, wherein: the pressure measurement control system consists of a mass flow controller, a high-precision pressure gauge, a vacuum gauge and a needle valve; the mass flow controller is positioned at an air inlet of the low-temperature saturation system, the high-precision pressure gauge is arranged at an air outlet of the low-temperature saturation system, the vacuum gauge is arranged at an air outlet of the low-temperature low-pressure measuring chamber system, and the needle valves are respectively positioned between the low-temperature saturation system and the low-temperature low-pressure measuring chamber system and at the outlet of the low-temperature low-pressure measuring chamber system and connected with the vacuum system.
6. A low temperature low pressure relative humidity standard device as claimed in claim 1 or 2, wherein: the vacuum system comprises a vacuum pump, a filter and an air pumping pipeline.
7. A low temperature low pressure relative humidity standard device as claimed in claim 1 or 2, wherein: the working mode of the device is that the device,
the device realizes saturated moisture under low temperature and normal pressure in a low temperature saturation system, and the saturated moisture under low temperature and normal pressure enters a low temperature and low pressure measuring chamber system through a gas pipeline to obtain standard gas with different humidity under low temperature and low pressure; the device realizes different low-temperature environments in a low-temperature saturation system and a low-temperature low-pressure measuring chamber system through a constant-temperature system, and realizes the low-pressure environments in a normal-pressure measuring chamber system and a low-temperature low-pressure measuring chamber system in the low-temperature saturation system under the combined action of a pressure measurement control system and a vacuum system; the device obtains standard gas with different humidity under certain temperature and pressure conditions by changing the temperature of the low-temperature saturation system, and can simultaneously carry out comprehensive calibration of temperature, pressure and relative humidity parameters.
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| CN202111561869.XA CN114384955A (en) | 2021-12-17 | 2021-12-17 | Low-temperature low-pressure relative humidity standard device |
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| CN202111561869.XA CN114384955A (en) | 2021-12-17 | 2021-12-17 | Low-temperature low-pressure relative humidity standard device |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201327427Y (en) * | 2008-12-24 | 2009-10-14 | 中国航空工业第一集团公司北京长城计量测试技术研究所 | Temperature and humidity measurement calibrating device |
| CN101794158A (en) * | 2010-03-26 | 2010-08-04 | 上海市计量测试技术研究院 | Gas pressure and flow control device of humidity generator |
| CN202939322U (en) * | 2012-11-30 | 2013-05-15 | 重庆四达试验设备有限公司 | Device for calibrating humidity dynamic response characteristics of sonde with double-flow method |
| CN205808448U (en) * | 2016-07-14 | 2016-12-14 | 香河国瑞智测试设备有限公司 | Portable humidity detection case |
| CN107943125A (en) * | 2016-12-08 | 2018-04-20 | 中国航空工业集团公司北京长城计量测试技术研究所 | A kind of automatic pressure regulation and control system of two-pressure method |
| CN112169668A (en) * | 2020-09-21 | 2021-01-05 | 河南省计量科学研究院 | Dynamic volume saturated gas generator and generation system based on condensation saturation |
-
2021
- 2021-12-17 CN CN202111561869.XA patent/CN114384955A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201327427Y (en) * | 2008-12-24 | 2009-10-14 | 中国航空工业第一集团公司北京长城计量测试技术研究所 | Temperature and humidity measurement calibrating device |
| CN101794158A (en) * | 2010-03-26 | 2010-08-04 | 上海市计量测试技术研究院 | Gas pressure and flow control device of humidity generator |
| CN202939322U (en) * | 2012-11-30 | 2013-05-15 | 重庆四达试验设备有限公司 | Device for calibrating humidity dynamic response characteristics of sonde with double-flow method |
| CN205808448U (en) * | 2016-07-14 | 2016-12-14 | 香河国瑞智测试设备有限公司 | Portable humidity detection case |
| CN107943125A (en) * | 2016-12-08 | 2018-04-20 | 中国航空工业集团公司北京长城计量测试技术研究所 | A kind of automatic pressure regulation and control system of two-pressure method |
| CN112169668A (en) * | 2020-09-21 | 2021-01-05 | 河南省计量科学研究院 | Dynamic volume saturated gas generator and generation system based on condensation saturation |
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