CN211121526U - pVTt method gas flow standard device with temperature control system - Google Patents
pVTt method gas flow standard device with temperature control system Download PDFInfo
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- CN211121526U CN211121526U CN201922157083.6U CN201922157083U CN211121526U CN 211121526 U CN211121526 U CN 211121526U CN 201922157083 U CN201922157083 U CN 201922157083U CN 211121526 U CN211121526 U CN 211121526U
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Abstract
The utility model discloses a pVTt method gas flow standard device with a temperature control system, which comprises a standard container, wherein the standard container is provided with a temperature constant guarantee component; the temperature control system comprises a heating element positioned in the constant temperature guarantee assembly, a cooling element positioned in the constant temperature guarantee assembly, and a controller connected with the heating element and the cooling element; the air inlet system comprises a detected nozzle connected with the standard container and a vacuum pump connected with the standard container; the detection system comprises a timing piece, a temperature measuring piece and a pressure measuring piece; and the pipeline system comprises a flow path pipeline for connecting the standard container, the air inlet system and the detection system. The utility model discloses device mechanism is simple reasonable effective, and the temperature field that can realize standard container fast is stable, has both kept pVTt method gas flow standard device's measurement accuracy, makes the time shorten greatly again, and this device mechanism is simple reasonable effective.
Description
Technical Field
The utility model belongs to the technical field of the standard device and specifically relates to a pVTt method gas flow standard device with temperature control system.
Background
The pVTt method gas flow standard device is a widely used primary gas flow standard metering device and equipment, has high accuracy grade, the uncertainty U of measurement can reach 0.07% or higher, and is generally used as a secondary standard for tracing the measurement value of critical flow meters such as Venturi nozzles, sonic nozzles and the like. The current widely adopted primary standard devices mainly comprise bell jar type, active piston type, pVTt method and mt method gas flow standard devices and the like. In the primary standard device, the volume of a standard container of the pVTt method gas flow standard device with a temperature control system is fixed, and parameters such as pressure, temperature and the like participating in flow calculation are measured in a static mode, so that the measurement accuracy of the device is easy to guarantee. At present, China has a multipurpose pVTt method gas flow standard device with a temperature control system, and the device works under normal pressure and micro-positive pressure, and the flow is only 1400m at most3And/h, the actual demand cannot be met. The pVTt method gas flow standard device has the following problems: in order to ensure the measurement accuracy of the pVTt method gas flow standard device, the temperature field must be sufficientThe average temperature and pressure in the standard container can be taken out for calculating mass flow under the condition of uniform and stable enough, the time consumption of vacuumizing the standard container with larger volume and stabilizing the temperature field after air inlet is finished is longer, about one hour is needed, and the whole time is longer.
SUMMERY OF THE UTILITY MODEL
This section is for the purpose of summarizing some aspects of embodiments of the invention and to briefly introduce some preferred embodiments, and in this section as well as in the abstract of the specification and the title of the application may be somewhat simplified or omitted to avoid obscuring the purpose of this section, the abstract of the specification and the title of the application, and such simplification or omission may not be used to limit the scope of the invention.
The present invention has been made in view of the above and/or other problems occurring in the prior art.
Therefore, the utility model aims to solve the technical problem that the temperature field is unstable when current pVTt method gas flow standard device tests, leads to the precision not high, efficiency is low excessively.
In order to solve the technical problem, the utility model provides a following technical scheme: a pVTt method gas flow standard device with a temperature control system comprises a standard container, a temperature constant guarantee component and a temperature control component, wherein the standard container is provided with the temperature constant guarantee component; the temperature control system comprises a heating element positioned in the constant temperature guarantee assembly, a cooling element positioned in the constant temperature guarantee assembly, and a controller connected with the heating element and the cooling element; the air inlet system comprises a detected nozzle connected with the standard container and a vacuum pump connected with the standard container; the detection system comprises a timing piece, a temperature measuring piece and a pressure measuring piece; and the pipeline system comprises a flow path pipeline for connecting the standard container, the air inlet system and the detection system.
As an optimized scheme of pVTt method gas flow standard device with temperature control system, wherein: and a first switch valve is arranged between the standard container and the detected nozzle, and a second switch valve is arranged between the standard container and the vacuum pump.
As an optimized scheme of pVTt method gas flow standard device with temperature control system, wherein: the pipeline system comprises a first pipeline, a second pipeline, a third pipeline, a fourth pipeline and a fifth pipeline.
As an optimized scheme of pVTt method gas flow standard device with temperature control system, wherein: the first switch valve is arranged on the first pipeline, one end of the first pipeline is connected to the detected nozzle, and the other end of the first pipeline is connected to the standard container; the second switch valve is arranged on the second pipeline, one end of the second pipeline is connected to the vacuum pump, and the other end of the second pipeline is connected to the standard container.
As an optimized scheme of pVTt method gas flow standard device with temperature control system, wherein: the timing piece is arranged on the third pipeline, one end of the third pipeline is connected to the first switch valve, and the other end of the third pipeline is connected to the timing piece. The temperature measuring piece is arranged on the fourth pipeline, one end of the fourth pipeline is connected with the temperature measuring piece, and the other end of the fourth pipeline is connected with the standard container. The pressure measuring and pressing piece is arranged on the fifth pipeline, one end of the fifth pipeline is connected with the pressure measuring and pressing piece, and the other end of the fifth pipeline is connected with the standard container.
As an optimized scheme of pVTt method gas flow standard device with temperature control system, wherein: the detection system further comprises an optical-electrical signal converter, the optical-electrical signal converter is arranged on the third pipeline, and the optical-electrical signal converter is located between the first switch valve and the timing piece.
As an optimized scheme of pVTt method gas flow standard device with temperature control system, wherein: the detection system further comprises an upper computer, and the timing piece, the temperature measuring piece and the pressure measuring piece are connected to the upper computer.
As an optimized scheme of pVTt method gas flow standard device with temperature control system, wherein: the standard container is provided with an air inlet and an air extraction opening, the air inlet is connected with the detected nozzle through the first pipeline, and the air extraction opening is connected with the vacuum pump through the second pipeline.
As an optimized scheme of pVTt method gas flow standard device with temperature control system, wherein: the temperature measuring part is a temperature sensor, and the pressure measuring part is a pressure sensor.
The utility model has the advantages that: the utility model discloses a cooperation control between sensor, heating member, cooling member and the controller etc. can realize the temperature field stability of standard container fast, has both kept the measurement accuracy of pVTt method device, makes the time shorten greatly again, and this device mechanism is simple reasonable effective.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without inventive labor. Wherein:
fig. 1 is a schematic diagram of a pVTt method gas flow calibration apparatus with a temperature control system according to a first embodiment of the present invention;
fig. 2 is a schematic diagram of a pVTt method gas flow calibration apparatus with a temperature control system according to a second embodiment of the present invention.
Fig. 3 is a schematic structural diagram of a pVTt method gas flow calibration apparatus with a temperature control system according to a second embodiment of the present invention.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention more comprehensible, embodiments accompanying the present invention are described in detail below with reference to the accompanying drawings.
In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be implemented in other ways different from the specific details set forth herein, and one skilled in the art may similarly generalize the present invention without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.
Next, the present invention will be described in detail with reference to the schematic drawings, and in the detailed description of the embodiments of the present invention, for convenience of illustration, the sectional view showing the device structure will not be enlarged partially according to the general scale, and the schematic drawings are only examples, and should not limit the scope of the present invention. In addition, the three-dimensional dimensions of length, width and depth should be included in the actual fabrication.
Further still, reference herein to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with at least one implementation of the invention is included. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.
Example 1
Referring to fig. 1, the embodiment provides a pVTt method gas flow calibration apparatus with a temperature control system, including a calibration container 100, the calibration container 100 is configured with a temperature constant guarantee assembly 101; an air intake system 300 including a nozzle 301 to be inspected connected to the standard container 100 and a vacuum pump 302 connected to the standard container 100, wherein a first on-off valve 303 is provided between the standard container 100 and the nozzle 301 to be inspected, and a second on-off valve 304 is provided between the standard container 100 and the vacuum pump 302; the detection system 400 comprises a timing piece 401, a temperature measuring piece 402 and a pressure measuring piece 403; and a piping system 500 including a flow path piping for connecting between the standard container 100, the air intake system 300, and the detection system 400. The detection system 400 comprises a timing piece 401, a temperature measuring piece 402 and a pressure measuring piece 403; and a piping system 500 including a flow path piping for connecting between the standard container 100, the air intake system 300, and the detection system 400.
The standard container 100 adopts the existing integral skid-mounted structure, and the skid-mounted structure is an integrated mode that functional components are integrated on an integral base and can be integrally mounted and moved; so-called skid mounting is conveniently carried out by moving and positioning equipment by using a skid bar, and comprises a table which is correspondingly installed with the standard container 100, and the standard container 100 is provided with a constant temperature guarantee assembly 101.
Preferably, a temperature constant guarantee assembly 101 is disposed outside the standard container 100 to maintain the outer surface of the standard container 100 at a constant temperature. Since the temperature measuring points are scientifically distributed at multiple points in the standard container 100, in a 34m standard container, each cubic meter is not less than 1 temperature measuring point, and the total number is not less than 50 temperature measuring points, in the case of a 3m standard container, the number of the temperature measuring points is not less than 8, and in the case of a 0.1m standard container, the number of the temperature measuring points is not less than 4, so as to reduce the measurement uncertainty caused by the non-uniform temperature of the gas in the standard container, in the embodiment, 42 temperature sensors are distributed in the standard container 100.
The utility model discloses a controller 203 controls the operating condition of heating member 201 and cooling member 202 to this realization is to the control of temperature.
Further, the pipe system 500 includes a first pipe 501, a second pipe 502, a third pipe 503, a fourth pipe 504, and a fifth pipe 505. The first switching valve 303 is arranged on a first pipeline 501, one end of the first pipeline 501 is connected with the detected nozzle 301, and the other end is connected with the standard container 100; the second on-off valve 304 is disposed on a second pipe 502, and one end of the second pipe 502 is connected to the vacuum pump 302 and the other end is connected to the standard container 100.
Further, a timing member 401 is provided on a third pipe 503, and one end of the third pipe 503 is connected to the first switching valve 303 and the other end is connected to the timing member 401. The temperature measuring member 402 is disposed on the fourth pipeline 504, and one end of the fourth pipeline 504 is connected to the temperature measuring member 402, and the other end is connected to the standard container 100. The pressure measuring element 403 is arranged on the fifth pipeline 505, one end of the fifth pipeline 505 is connected with the pressure measuring element 403, and the other end is connected with the standard container 100.
Preferably, the temperature measuring member 402 is a temperature sensor, and the pressure measuring member 403 is a pressure sensor. After the sensor collects the measurement data, the corresponding detected numerical value is displayed on the temperature value and pressure value display instrument.
The detection system 400 further includes an optical-to-electrical signal converter 404, the optical-to-electrical signal converter 404 being disposed on the third pipeline 503, the optical-to-electrical signal converter 404 being located between the first on-off valve 303 and the timing member 401. The photoelectric signal converter 404 transmits data of the first switching valve 303 to the timer 401.
The pre-aeration equilibrium state parameters and the in-tank gas parameters five minutes after aeration and the water bath temperature in the standard vessel 100 were measured. And (3) establishing a prediction model of temperature difference, pressure and temperature by adopting big data processing on the temperature difference between the average temperature of the gas in the tank body and the water bath temperature measured five minutes after air inlet and the pressure data in the tank body, and calculating the detection mass flow of the device by predicting the values of the pressure and the temperature in the tank body in a steady state and using a related formula.
Example 2
Referring to fig. 3, a second embodiment of the present invention is based on the previous embodiment, and is different from the previous embodiment in that: the detection system 400 further comprises an upper computer 405, a timing piece 401, a temperature measuring piece 402 and a pressure measuring piece 403 which are all connected to the upper computer 405.
Specifically, the invention comprises a standard container 100, wherein the standard container 100 is provided with a constant temperature guarantee assembly 101; an air intake system 300 including a nozzle 301 to be inspected connected to the standard container 100 and a vacuum pump 302 connected to the standard container 100, wherein a first on-off valve 303 is provided between the standard container 100 and the nozzle 301 to be inspected, and a second on-off valve 304 is provided between the standard container 100 and the vacuum pump 302; the detection system 400 comprises a timing piece 401, a temperature measuring piece 402 and a pressure measuring piece 403; and a piping system 500 including a flow path piping for connecting between the standard container 100, the air intake system 300, and the detection system 400. The detection system 400 comprises a timing piece 401, a temperature measuring piece 402 and a pressure measuring piece 403; and a piping system 500 including a flow path piping for connecting between the standard container 100, the air intake system 300, and the detection system 400.
Further, the pipe system 500 includes a first pipe 501, a second pipe 502, a third pipe 503, a fourth pipe 504, and a fifth pipe 505. The first switching valve 303 is arranged on a first pipeline 501, one end of the first pipeline 501 is connected with the detected nozzle 301, and the other end is connected with the standard container 100; the second on-off valve 304 is disposed on a second pipe 502, and one end of the second pipe 502 is connected to the vacuum pump 302 and the other end is connected to the standard container 100.
Further, a timing member 401 is provided on a third pipe 503, and one end of the third pipe 503 is connected to the first switching valve 303 and the other end is connected to the timing member 401. The temperature measuring member 402 is disposed on the fourth pipeline 504, and one end of the fourth pipeline 504 is connected to the temperature measuring member 402, and the other end is connected to the standard container 100. The pressure measuring element 403 is arranged on the fifth pipeline 505, one end of the fifth pipeline 505 is connected with the pressure measuring element 403, and the other end is connected with the standard container 100.
Preferably, the temperature measuring member 402 is a temperature sensor, and the pressure measuring member 403 is a pressure sensor. After the sensor collects the measurement data, the corresponding detected numerical value is displayed on the temperature value and pressure value display instrument.
The detection system 400 further includes an optical-to-electrical signal converter 404, the optical-to-electrical signal converter 404 being disposed on the third pipeline 503, the optical-to-electrical signal converter 404 being located between the first on-off valve 303 and the timing member 401. The photoelectric signal converter 404 transmits data of the first switching valve 303 to the timer 401.
After data are collected, the data of the timing part 401, the temperature measuring part 402 and the pressure measuring part 403 are all transmitted to the upper computer 405, a prediction model of temperature difference, pressure and temperature is established for the temperature difference between the average temperature of gas in the tank body and the water bath temperature measured five minutes after gas inlet and the pressure data in the tank body by adopting big data processing, and the detection mass flow of the device can be calculated by predicting the values of the pressure and the temperature in the tank body in a steady state and utilizing a correlation formula.
The utility model discloses specific theory of operation specifically as follows:
before starting, the standard container 100 is selected according to the flow rate, the second on-off valve 304 is opened, the standard container 100 is evacuated by the vacuum pump 302, and the second on-off valve 304 is closed. The temperature and pressure of the standard container 100 are measured according to the above-mentioned sensors when the vacuum is applied, the temperature in the standard container 100 is adjusted to be stable by the controller 203, and the temperature and pressure of the gas in the standard container 100 are measured after the temperature of the gas in the standard container 100 is stable.
The first on-off valve 303 is opened to start the timer 401. The atmospheric air passes through the test nozzle 301 and the first switching valve 303, and the air continues to flow into the standard container 100 at a constant flow rate. After the standard container 100 is full, the first switching valve 303 is closed, and the timer 401 is stopped. And at the same time, the temperature inside the standard container 100 is regulated and stabilized again by using the constant temperature guarantee assembly 101, and the temperature and the pressure of the gas inside the standard container 100 are measured after the temperature of the gas inside the standard container 100 is stabilized. The theoretical mass flow through the inspected nozzle 301 can be measured.
It is important to note that the construction and arrangement of the present application as shown in the various exemplary embodiments is illustrative only. Although only a few embodiments have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters (e.g., temperatures, pressures, etc.), mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited in this application. For example, elements shown as integrally formed may be constructed of multiple parts or elements, the position of elements may be reversed or otherwise varied, and the nature or number of discrete elements or positions may be altered or varied. Accordingly, all such modifications are intended to be included within the scope of this invention. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. In the claims, any means-plus-function clause is intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Other substitutions, modifications, changes and omissions may be made in the design, operating conditions and arrangement of the exemplary embodiments without departing from the scope of the present inventions. Therefore, the present invention is not limited to a particular embodiment, but extends to various modifications that nevertheless fall within the scope of the appended claims.
Moreover, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not be described (i.e., those unrelated to the presently contemplated best mode of carrying out the invention, or those unrelated to enabling the invention).
It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation.
It should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting, and although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be modified or replaced with equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should be covered by the scope of the claims of the present invention.
Claims (9)
1. A pVTt method gas flow standard device with a temperature control system is characterized in that: comprises the steps of (a) preparing a mixture of a plurality of raw materials,
a standard container (100), the standard container (100) being provided with a constant temperature guarantee assembly (101);
a temperature control system (200) comprising a heating element (201) located within the constant temperature assurance assembly (101), a cooling element (202) located within the constant temperature assurance assembly (101), and a controller (203) connected to the heating element (201) and the cooling element (202);
an air intake system (300) including a nozzle (301) to be inspected connected to the standard container (100), and a vacuum pump (302) connected to the standard container (100);
the detection system (400) comprises a timing piece (401), a temperature measuring piece (402) and a pressure measuring piece (403); and the number of the first and second groups,
a piping system (500) comprising a flow path piping for connecting between the standard container (100), the air intake system (300), and the detection system (400).
2. The pVTt method gas flow calibration device with temperature control system according to claim 1, wherein: a first switch valve (303) is arranged between the standard container (100) and the detected nozzle (301), and a second switch valve (304) is arranged between the standard container (100) and the vacuum pump (302).
3. The pVTt method gas flow calibration device with temperature control system according to claim 2, wherein: the pipe system (500) comprises a first pipe (501), a second pipe (502), a third pipe (503), a fourth pipe (504) and a fifth pipe (505).
4. The pVTt method gas flow calibration device with temperature control system according to claim 3, wherein: the first switch valve (303) is arranged on the first pipeline (501), one end of the first pipeline (501) is connected to the detected nozzle (301), and the other end of the first pipeline (501) is connected to the standard container (100);
the second switch valve (304) is arranged on the second pipeline (502), one end of the second pipeline (502) is connected to the vacuum pump (302), and the other end is connected to the standard container (100).
5. The pVTt method gas flow standard device with temperature control system of claim 4, wherein: the timing piece (401) is arranged on the third pipeline (503), one end of the third pipeline (503) is connected to the first switch valve (303), and the other end of the third pipeline is connected to the timing piece (401);
the temperature measuring piece (402) is arranged on the fourth pipeline (504), one end of the fourth pipeline (504) is connected with the temperature measuring piece (402), and the other end of the fourth pipeline (504) is connected with the standard container (100);
the pressure measuring element (403) is arranged on the fifth pipeline (505), one end of the fifth pipeline (505) is connected with the pressure measuring element (403), and the other end is connected with the standard container (100).
6. The pVTt method gas flow standard device with a temperature control system, according to claim 5, wherein: the detection system (400) further comprises an optical-to-electrical signal converter (404), wherein the optical-to-electrical signal converter (404) is arranged on the third pipeline (503), and the optical-to-electrical signal converter (404) is positioned between the first switching valve (303) and the timing piece (401).
7. The pVTt method gas flow calibration device with temperature control system according to claim 6, wherein: the detection system (400) further comprises an upper computer (405), and the timing piece (401), the temperature measuring piece (402) and the pressure measuring piece (403) are connected to the upper computer (405).
8. The pVTt method gas flow calibration device with temperature control system according to claim 7, wherein: the standard container (100) is provided with an air inlet (100a) and an air extraction opening (100b), the air inlet (100a) is connected with the detected nozzle (301) through the first pipeline (501), and the air extraction opening (100b) is connected with the vacuum pump (302) through the second pipeline (502).
9. The pVTt method gas flow calibration device with temperature control system according to claim 8, wherein: the temperature measuring part (402) is a temperature sensor, and the pressure measuring part (403) is a pressure sensor.
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| CN201922157083.6U CN211121526U (en) | 2019-12-05 | 2019-12-05 | pVTt method gas flow standard device with temperature control system |
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| CN201922157083.6U CN211121526U (en) | 2019-12-05 | 2019-12-05 | pVTt method gas flow standard device with temperature control system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112067086A (en) * | 2020-08-11 | 2020-12-11 | 镇江市计量检定测试中心 | Jar internal temperature field measurement system of large-scale pVTt metering tank |
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2019
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112067086A (en) * | 2020-08-11 | 2020-12-11 | 镇江市计量检定测试中心 | Jar internal temperature field measurement system of large-scale pVTt metering tank |
| CN112067086B (en) * | 2020-08-11 | 2021-04-13 | 镇江市计量检定测试中心 | Jar internal temperature field measurement system of large-scale pVTt metering tank |
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