CN201607418U - Low frost-point humidity standard generation device - Google Patents
Low frost-point humidity standard generation device Download PDFInfo
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- CN201607418U CN201607418U CN2009202781147U CN200920278114U CN201607418U CN 201607418 U CN201607418 U CN 201607418U CN 2009202781147 U CN2009202781147 U CN 2009202781147U CN 200920278114 U CN200920278114 U CN 200920278114U CN 201607418 U CN201607418 U CN 201607418U
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Abstract
The utility model relates to a low frost-point humidity standard generation device which comprises a nitrogen storage tank, pressure reducing valves and a mass flowmeter, and is characterized in that the nitrogen storage tank stores liquid nitrogen, high-purity nitrogen output by the nitrogen storage tank through gasification of the liquid nitrogen passes through a first pressure reducing valve and a gas purifier in sequence and is then divided into two paths: one path passes through the mass flowmeter and is communicated with an inlet of a pre-saturator via a first heat exchanger, and an outlet of the pre-saturator is communicated with the inlet of an ice saturator through a second heat exchanger; the other path is communicated with a gas outlet pipeline of the ice saturator through the mass flowmeter, and the pipeline which is converged together is led to a gas outlet pipe through a second pressure reducing valve and a straight-through valve; the pre-saturator and the first heat exchanger are arranged in a pre-saturation groove; and the ice saturator and the second heat exchanger are arranged in a saturation groove. The generation device is the humidity generation device with high accuracy, the dew point measurement range of the humidity detection achieves minus 75 DEG C-minus 25 DEG C, the uncertainty of dew point measurement is 0.04 DEG C-0.10 DEG C, and the generation device further has the capacity of generating the dew point of minus 100 DEG C.
Description
Technical field
The utility model relates to a kind of humidity standard generating means, specifically is a kind of generating means of low frost point humidity standard.
Background technology
Humidity is an important environmental parameter, and it not only has influence on people's quality of life, also has influence on production run and product qualities such as industry, agricultural, national defence.The hygronom instruments and meters is widely used in fields such as Aero-Space, microelectronics, atomic energy, petrochemical industry, electric power, meteorology, storage, at Chinese hygronom instruments and meters very big market is arranged.Along with modern science and technology and fast development of national economy, the measurement of humidity and the requirement of control are also improved day by day, especially aerospace industry, microelectronics industry, atomic energy industry, aspects such as petrochemical complex industry and power industry, it not only has influence on the quality of product, and is related to problem such as safety in production
[2-5]Set up high-caliber national psychrometry standard set-up, all seem extremely important and urgent for the sound development of Chinese national economy and the accurate and unification of international comparison work and China's humidity value.
Humidity measurement method has a lot, and wherein wt method hygrometer is acknowledged as the highest absolute method of measurement of accuracy, as humidity transmission of quantity value benchmark
[2], gravimetric method reference humidity instrumentation weight range is less, and gravimetric method standard humidity meter must just can carry out the transmission of quantity value use with the outfit of reference humidity generator.The standard humidity source that is used for the humidity transmission of quantity value below dewpoint temperature-30 ℃, the standard humidity generator that uses both at home and abroad has two platen press humidity generators, dual-temperature process humidity generator, shunting humidity generator and osmos tube humidity generator at present
[2]Aspect the Humidity Detection of low frost point particularly below frost point-70 ℃, classics are more accurate more than two platen press humidity generators for the low frost point Humidity Detection standard set-up of single platen press, and are that structure is the basis of hanging down frost point pair platen press humidity generators.
China lacks and is used for the low frost point Humidity Detection standard set-up that humidity transmission of quantity value dew point scope reaches-75 ℃～-25 ℃ at present.The frost of existing pair of platen press humidity generator of China/dew point scope is-25 ℃～+ 25 ℃, and the uncertainty of frost/dew point is 0.04 ℃, reaches international similar standard utensil advanced level in this frost/dew point scope
[13,14]But there is a certain distance in its frost/dew point measurement range (25 ℃～+ 25 ℃) with international most advanced level (75 ℃～+ 25 ℃).We have the humidity value of a very big segment limit can not participate in international comparison, and domestic humidity transmission of quantity value also is affected.Therefore, the low frost point Humidity Detection standard set-up of development has very crucial effect for the international comparison and the domestic humidity transmission of quantity value of China's humidity value.
Summary of the invention
The purpose of this utility model is: for frost/dew point scope of overcoming existing pair of platen press humidity generator of China is-25 ℃～+ 25 ℃, the uncertainty of frost/dew point is 0.04 ℃ a deficiency, fill up China and be used for the disappearance that humidity transmission of quantity value dew point scope reaches-75 ℃～-25 ℃ low frost point Humidity Detection standard set-up, a kind of generating means of low frost point humidity standard is provided, the dew point measurement range of its Humidity Detection reaches-75 ℃～-25 ℃, the dew point Measurement Uncertainty is 0.04 ℃～0.10 ℃, and has the ability of generation dew point-100 ℃.
The technical solution of the utility model is achieved in that a kind of generating means of low frost point humidity standard, comprise: nitrogen storage tank, reduction valve, mass flowmeter, described nitrogen storage tank is a liquid nitrogen, by the high pure nitrogen of the liquid nitrogen gasification of nitrogen storage tank output successively through being divided into two-way behind first reduction valve, the gas purifier: the mass flowmeter of leading up to is communicated with the inlet of presaturator through first heat interchanger, and the outlet of presaturator is communicated with the inlet of ice saturator by second heat interchanger; Another road: be communicated with by the outlet pipe of mass flowmeter with the ice saturator, the pipeline that converges together passes through second reduction valve, straight-through valve successively to escape pipe; The described presaturator and first heat interchanger are arranged in the presaturation groove; The described ice saturator and second heat interchanger are arranged in the saturated groove.
Described presaturator is to be made of cell body and permeable mass, and described permeable mass is made of its middle osmos tube of skeleton and winding, and the inlet and the outlet of osmos tube are separately positioned on outside the cell body.
Described ice saturator is to be made of housing, column plate, middle draft tube, top escape pipe and chassis, described middle draft tube and chassis are affixed to be the T font, middle draft tube is communicated with housing bottom, the staggered up and down column plate that overlaps square position shape column plate and be provided with ring crossette shape of middle draft tube; Described column plate is connected with the top escape pipe, and described middle draft tube is communicated with into tracheae.
The utility model ultimate principle is according to the thermodynamics gas-solid biphase equilibrium principle design of water, it is to adopt single platen press to make drying nitrogen arrive the osmos tube presaturator through the heat interchanger heat exchange under the pressure stable state, and then by entering the ice saturator after the heat interchanger heat exchange to carry out the ice face saturated, can obtain the constant humidity source of the gas, its humidity value can accurately be measured according to saturated room temperature and pressure.Change saturated room temperature, just can obtain the constant source of the gas of desired moisture level.The frost point measurement range of its Humidity Detection reaches-75 ℃～-25 ℃, and the dew point Measurement Uncertainty is 0.04 ℃～0.10 ℃, and has the ability of generation dew point-100 ℃.
Description of drawings
Fig. 1 is a principle process synoptic diagram of the present utility model;
Fig. 2 is the saturator structural representation of Fig. 1;
Fig. 3 is that the saturator K of Fig. 2 is to structural representation;
Fig. 4 is the prominent ring tower plate structure of being provided with of a saturator synoptic diagram;
Fig. 5 is that the A of Fig. 4 is to synoptic diagram;
Fig. 6 is the flat tower plate structure synoptic diagram of saturator;
Fig. 7 is the A-A structural representation of Fig. 6;
The presaturator structural representation that Fig. 8 is;
Fig. 9 is a permeable mass cross-sectional view among Fig. 8;
Figure 10 is that the A of Fig. 9 is to structural representation.
Embodiment
Embodiment
A kind of generating means of low frost point humidity standard, as shown in Figure 1, comprise: nitrogen storage tank 1, reduction valve 2, mass flowmeter, described nitrogen storage tank 1 is a liquid nitrogen, by the high pure nitrogen of the liquid nitrogen gasification of nitrogen storage tank 1 output successively through being divided into two-way behind first reduction valve 2, the gas purifier 3: the mass flowmeter 5 of leading up to is communicated with the inlet 701 of presaturators 7 through first heat interchanger 6, and the outlet 704 of presaturator 7 is communicated with the inlet of ice saturators 9 through second heat interchanger 6; Another road: be communicated with by the outlet pipe of mass flowmeter 4 with ice saturator 9, the pipeline that converges together passes through second reduction valve 12, straight-through valve 11 successively to escape pipe; Described presaturator 7 is arranged in the presaturation groove 8, and the described presaturator 7 and first heat interchanger 6 are arranged in the presaturation groove 8; The described ice saturator 9 and second heat interchanger 6 are arranged in the saturated groove 10.
Described presaturator 7 is to be made of cell body 705 and permeable mass, and described permeable mass is made of skeleton 703 and the osmos tube 702 that twines in the middle of it, the inlet 701 of osmos tube 702 and export 704 and be separately positioned on outside the cell body 705.Shown in Fig. 8-10.
Described ice saturator 9 is to be made of with chassis 903 housing 905, column plate, middle draft tube 901, top escape pipe 904, in the middle of described draft tube 901 and chassis 903 affixed be the T font, middle draft tube 901 is communicated with housing 905 bottoms, the staggered up and down column plate 906 that overlaps square position shape column plate 902 and be provided with ring crossette shape of middle draft tube 901; Described column plate top is connected with top escape pipe 904, and described middle draft tube 901 is communicated with to go into tracheae.Shown in Fig. 2-7.
The technology path of the generating means of this low frost point humidity standard is to make the dry gas state that reaches capacity under each stationary temperature.From its principle of work as can be known, the key of the generating means of the low frost point humidity standard of manufacturing is:
1., manufacture and design presaturator and saturation degree near 100% ice saturator.
2., development one cover high accuracy temperature control equipment, the temperature control scope is-80 ℃～+ 30 ℃ a thermostatic equipment, the fluctuation degree of temperature is ± 0.01 ℃, temperature uniformity is 0.02 ℃.
3., research and development one cover pressure collecting and measuring system, when saturated chamber pressure and atmospheric pressure measurement, the precision of the measurement of pressure is better than ± 0.02%.
4., development one cover degree of depth moisture drying air supply system, frost point is less than-100 ℃.
Adopted following multinomial gordian technique in the design of the generating means of this low frost point humidity standard:
Air supply system, nitrogen storage tank 1, reduction valve 2, mass flowmeter, presaturator 7, ice saturator 9 gordian techniquies.
(1) air supply system: the high pure nitrogen that adopts liquid nitrogen gasification output adds gas purifier as dry source of the gas, and dew point can be reached below-100 ℃.
(2) saturator system: be made up of the heat exchanger tube and the ice saturator that are placed in the saturated groove of constant temperature, the ice saturator adopts the column plate type sandwich construction.
(3) presaturator system:, need carry out presaturation to gas in order to obtain fully saturated moisture.Presaturator is selected the osmos tube humidity generator for use, and pre-saturated dewpoint temperature is general than the high several years of the dewpoint temperature that requires to reach.
(4) constant temperature system: the generating means operation of low frost point humidity standard is the process of carrying out under a constant temperature, and it is saturated to require saturated chamber to carry out under a constant temperature, and can change saturation temperature as required, need realize with calibration cell.Temperature non and stability according to the accuracy requirement calibration cell of generator should be controlled at 0.02 ℃ and ± 0.01 ℃ respectively.Constant temperature system comprises refrigeration machine, refrigerator, well heater, stirrer, calibration cell etc.
(5) pressure acquisition measuring system: the generating means of low frost point humidity standard requires the pressure and the atmospheric pressure of saturated chamber are measured accurately.
The workflow of being somebody's turn to do the generating means that hangs down the frost point humidity standard is as follows:
Described nitrogen storage tank 1 is a liquid nitrogen, high pure nitrogen by gasification output is divided into two pipelines by pipeline behind first reduction valve 2 and gas purifier 3, one the tunnel: enter presaturator 7 through first heat interchanger 6 by mass flowmeter 5, by regulating the temperature of first heat interchanger, the 6 adjusting presaturation grooves 8 in the presaturation groove 8, thereby obtain the presaturation moisture, the frost point temperature of presaturator 7 outlets is general than the high several years of frost point temperature that require to reach, the moisture of presaturator 7 outputs is imported ice saturator 9 through second heat interchanger 6, change the temperature of icing saturated groove 10 by second heat interchanger 6 in the saturated groove 10, just can obtain the constant source of the gas of desired moisture level; Another road: converge by the outlet pipe of mass flowmeter 4 with ice saturator 9, the gas circuit after converging is passed through second reduction valve 12, straight-through valve 11, by the temperature and pressure of accurate mensuration ice saturator, and current atmospheric pressure.The data acquisition measuring system will be finished data processing automatically, calculates the result of humidity value and the frost point of constant humidity source of the gas is presented on the panel screen.If reach its technical indicator after needing lower frost point the moisture of saturator output can be diluted with another strand dry gas:
1, liquid nitrogen gasification and degree of depth moisture purified gas source supplying system:
In order to prevent that the moisture in the carrier gas from freezing and blocking pipe at low temperatures, the high pure nitrogen that adopts liquid nitrogen gasification output can make the air-flow dew point can reach below-100 ℃ as dry source of the gas by purification system degree of depth moisture drying.The reply pipeline carries out the dry gas purging before measuring, and guarantees the pipeline drying.
2, gordian technique ice saturator 9 is superposition type saturators:
Saturator is the device that produces saturated with moisture, is the important component part of humidity generator.The performance of humidity generator and the structure of saturator and efficient are closely related.The ice saturator of the generating means of low frost point humidity standard adopts superposition type plate column plate structure, and the characteristics of this structure are the surface areas that as far as possible increases ice in the space of a compactness, to increase the chance of gas-solid mass transfer.Produce an amount of ice in every layer of column plate, gas enters at the bottom of tower, weaves throngh on the ice face of column plate, and saturated gas is from the top output of column plate.Change the constant source of the gas that saturated room temperature just can obtain desired moisture level, this structure can provide the saturated gas of gas flow broad.The presaturation moisture reaches capacity through heat interchanger and enters the ice saturator after the groove temperature, and it is very little that air-flow reaches the low saturated required vapour quantity of frost point, so the distillation of ice and the coagulation of water vapor can not cause icing the significant change of face height.Obtain the frost point temperature of saturated with moisture by the temperature and pressure of measuring ice saturator endpiece gas.
3, presaturator 7 adopts osmos tube humidity generator presaturation system:
Often need to increase presaturator in order to reach desirable saturation degree.The moisture frost point that adopts the output of osmos tube presaturator imports the ice saturator again near after icing saturation temperature.Design is in order to increase the saturation degree of ice saturator, to make its saturation degree reach 100% like this.
Adopt the osmos tube humidity generator as presaturator, the osmos tube humidity generator
[2]Itself can be used as the psychrometry utensil, and simple in structure, easy to operate, accuracy can be satisfied the requirement of the general psychrometry utensil of assay calibration, has the little and advantages of cheap price of volume simultaneously.So select presaturator for use the osmos tube humidity generator, its dew point scope is set to-70 ℃～-15 ℃, differs less with ice saturator dew point, and required dry gas consumption is less, is fit to very much do the presaturator of the generating means that hangs down the frost point humidity standard.Osmos tube is the core component of whole presaturator.Not contaminated in order to guarantee osmos tube, water jacket design in the presaturation calibration cell adopts, inside groove is a stainless steel structure, and the inside is a distilled water, and osmos tube just is placed in the inside groove.The permeability of water and the material of pipe, length, caliber, pipe thickness are relevant, and for the certain osmos tube of specification, after the flow of carrier gas was fixing, temperature was unique determinative of output gas humidity value.Just can obtain presaturation constant humidity gas by the temperature of regulating the presaturator calibration cell.
The said equipment detail is as follows:
。
Claims (3)
1. the generating means of a low frost point humidity standard, comprise: nitrogen storage tank (1), reduction valve (2), mass flowmeter, it is characterized in that: described nitrogen storage tank (1) is a liquid nitrogen, high pure nitrogen by the output of the liquid nitrogen gasification of nitrogen storage tank (1) is divided into two-way through first reduction valve (2), gas purifier after (3) successively: the mass flowmeter (5) of leading up to is communicated with the inlet (701) of presaturator (7) through first heat interchanger (6), and the outlet (704) of presaturator (7) is communicated with the inlet of ice saturator (9) through second heat interchanger (6); Another road: be communicated with by the outlet pipe of mass flowmeter (4) with ice saturator (9), the pipeline that converges together passes through second reduction valve (12), straight-through valve (11) successively to escape pipe; Described presaturator (7) and first heat interchanger (6) are arranged in the presaturation groove (8); Described ice saturator (9) and second heat interchanger (6) are arranged in the saturated groove (10).
2. the generating means of low frost point humidity standard as claimed in claim 1, it is characterized in that: described presaturator (7) is to be made of cell body (705) and permeable mass, described permeable mass is made of its middle osmos tube (702) of skeleton (703) and winding, and the inlet (701) of osmos tube (702) and outlet (704) are separately positioned on outside the cell body (705).
3. the generating means of low frost point humidity standard as claimed in claim 1, it is characterized in that: described ice saturator (9) is to be made of with chassis (903) housing (905), column plate, middle draft tube (901), top escape pipe (904), described middle draft tube (901) is affixed with chassis (903) to be the T font, middle draft tube (901) is communicated with housing (905) bottom, the staggered up and down column plate (906) that overlaps square position shape column plate (902) and be provided with ring crossette shape of middle draft tube (901); Described column plate is connected with top escape pipe (904), and described middle draft tube (901) is communicated with to go into tracheae.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009202781147U CN201607418U (en) | 2009-12-11 | 2009-12-11 | Low frost-point humidity standard generation device |
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| CN2009202781147U CN201607418U (en) | 2009-12-11 | 2009-12-11 | Low frost-point humidity standard generation device |
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| CN201607418U true CN201607418U (en) | 2010-10-13 |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104061955A (en) * | 2014-07-15 | 2014-09-24 | 国家电网公司 | Verification platform for sulfur hexafluoride gas humidity sensor under pressure |
| CN105547350A (en) * | 2015-12-08 | 2016-05-04 | 中国航空工业集团公司北京长城计量测试技术研究所 | Humidity generation ice surface saturator |
| CN106644817A (en) * | 2016-12-21 | 2017-05-10 | 华北电力大学 | Nitrogen saturated steam pressure measuring device based on engineering thermodynamics |
| CN107607676A (en) * | 2017-09-07 | 2018-01-19 | 中国计量科学研究院 | System occurs for traces of moisture standard in gas |
| CN109813756A (en) * | 2019-02-01 | 2019-05-28 | 中国石油天然气集团公司 | A kind of method of gas pipeline water dew point on-line real-time measuremen |
| CN110488899A (en) * | 2019-09-02 | 2019-11-22 | 中航长城计量测试(天津)有限公司 | A kind of auxiliary heating type humidity generator |
| CN110531810A (en) * | 2019-09-02 | 2019-12-03 | 中航长城计量测试(天津)有限公司 | A kind of preliminary condensation formula humidity generator |
| CN111398349A (en) * | 2020-04-02 | 2020-07-10 | 中国航空工业集团公司北京长城计量测试技术研究所 | Flow proportioning device, dew point generator and flow proportioning method |
| CN113948032A (en) * | 2021-02-03 | 2022-01-18 | 友达光电股份有限公司 | Pixel circuit and driving method thereof |
| CN114047226A (en) * | 2021-11-02 | 2022-02-15 | 中国航空工业集团公司北京长城计量测试技术研究所 | Gas dew point generating device |
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2009
- 2009-12-11 CN CN2009202781147U patent/CN201607418U/en not_active Expired - Fee Related
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104061955A (en) * | 2014-07-15 | 2014-09-24 | 国家电网公司 | Verification platform for sulfur hexafluoride gas humidity sensor under pressure |
| CN105547350A (en) * | 2015-12-08 | 2016-05-04 | 中国航空工业集团公司北京长城计量测试技术研究所 | Humidity generation ice surface saturator |
| CN106644817A (en) * | 2016-12-21 | 2017-05-10 | 华北电力大学 | Nitrogen saturated steam pressure measuring device based on engineering thermodynamics |
| CN107607676A (en) * | 2017-09-07 | 2018-01-19 | 中国计量科学研究院 | System occurs for traces of moisture standard in gas |
| CN109813756A (en) * | 2019-02-01 | 2019-05-28 | 中国石油天然气集团公司 | A kind of method of gas pipeline water dew point on-line real-time measuremen |
| CN110488899A (en) * | 2019-09-02 | 2019-11-22 | 中航长城计量测试(天津)有限公司 | A kind of auxiliary heating type humidity generator |
| CN110531810A (en) * | 2019-09-02 | 2019-12-03 | 中航长城计量测试(天津)有限公司 | A kind of preliminary condensation formula humidity generator |
| CN110531810B (en) * | 2019-09-02 | 2021-05-28 | 中航长城计量测试(天津)有限公司 | Pre-condensing type humidity generator |
| CN111398349A (en) * | 2020-04-02 | 2020-07-10 | 中国航空工业集团公司北京长城计量测试技术研究所 | Flow proportioning device, dew point generator and flow proportioning method |
| CN113948032A (en) * | 2021-02-03 | 2022-01-18 | 友达光电股份有限公司 | Pixel circuit and driving method thereof |
| CN113948032B (en) * | 2021-02-03 | 2023-09-29 | 友达光电股份有限公司 | Pixel circuit and driving method thereof |
| CN114047226A (en) * | 2021-11-02 | 2022-02-15 | 中国航空工业集团公司北京长城计量测试技术研究所 | Gas dew point generating device |
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Granted publication date: 20101013 Termination date: 20111211 |