CN117633404A - Gas volume flow conversion method for heat exchanger air resistance measurement in open environment - Google Patents
Gas volume flow conversion method for heat exchanger air resistance measurement in open environment Download PDFInfo
- Publication number
- CN117633404A CN117633404A CN202311602807.8A CN202311602807A CN117633404A CN 117633404 A CN117633404 A CN 117633404A CN 202311602807 A CN202311602807 A CN 202311602807A CN 117633404 A CN117633404 A CN 117633404A
- Authority
- CN
- China
- Prior art keywords
- under
- working condition
- air
- volume flow
- wet air
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 27
- 238000005259 measurement Methods 0.000 title claims abstract description 23
- 238000006243 chemical reaction Methods 0.000 title claims abstract description 18
- 238000013461 design Methods 0.000 claims abstract description 30
- 238000012360 testing method Methods 0.000 claims abstract description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 50
- 239000012530 fluid Substances 0.000 claims description 15
- 229920006395 saturated elastomer Polymers 0.000 claims description 5
- 239000000126 substance Substances 0.000 claims description 4
- 230000007613 environmental effect Effects 0.000 description 2
- 238000007792 addition Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000007791 dehumidification Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Landscapes
- Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
Abstract
The invention belongs to the technical field of thermal parameter measurement and control, and discloses a gas volume flow conversion method for measuring the gas resistance of a heat exchanger in an open environment, which is used for measuring the dry air volume flow in a measured channel under a design working condition, wherein the measured channel is connected with a wind measurement box through a connecting pipe, and the gas volume flow conversion method for measuring the gas resistance of the heat exchanger in the open environment comprises the following steps: acquiring actual test working condition parameters based on an air volume measuring box, and converting wet air volume flow under the actual working condition into dry air volume flow under the same temperature and the same pressure according to the actual test working condition parameters; and converting the dry air volume flow under the same temperature and pressure as the actual working condition into the dry air volume flow in the measured channel under the specific temperature and the specific pressure in the design working condition. According to the method, the wet air volume flow in the actual working environment is converted into the dry air volume flow under the design working condition, so that a more accurate air resistance measurement result is obtained.
Description
Technical Field
The invention belongs to the technical field of thermal parameter measurement and control, and particularly relates to a method for converting gas volume flow required by high-precision measurement of air resistance of a heat exchanger in an open environment.
Background
The plate-fin heat exchanger has the advantages of high heat transfer efficiency, compact structure, wide application temperature range and the like as a typical compact heat exchanger, and is widely applied to various fields of petrochemical industry, low-temperature air separation, aerospace and the like; the air resistance of the heat exchanger is an important factory index. When the air resistance of the heat exchanger is detected, a specific design working condition (temperature T is needed to be provided for the heat exchanger 2 Pressure p 2 ) The air flow (volume flow) of the dry air is stabilized, so that the air resistance of the tested channel in the heat exchanger is determined under the flow.
However, when the heat exchanger air resistance measurement is performed in an open environment, the temperature T of the gas under actual conditions 1 Pressure p 1 Is different from the design working condition, and it is difficult to ensure that the air contains no moisture (namely, the relative humidity psi is not equal to 0), if the influence of the thermal parameters is not considered, even if the volume flow of the gas is the same, the air resistance measurement result can generate a certain error. Therefore, the temperature T of the actual working condition is required 1 Pressure p 1 And the humidity psi and other influencing factors are taken into consideration to obtain the volume flow of the gas after temperature, pressure and humidity correction, and more accurate results can be obtained by carrying out air resistance measurement under the flow.
Disclosure of Invention
The invention aims to provide a gas volume flow conversion method for measuring the air resistance of a heat exchanger in an open environment, which converts the wet air volume flow in an actual working environment into the dry air volume flow under a design working condition, thereby obtaining a more accurate air resistance measurement result.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
the utility model provides a gas volume flow conversion method of heat exchanger air resistance measurement under open environment for to the dry air volume flow measurement in the measured passageway under the design operating mode, the measured passageway is connected with the amount of wind measurement case through the connecting pipe, heat exchanger air resistance measuring gas volume flow conversion method under open environment includes:
acquiring actual test working condition parameters based on an air volume measuring box, and converting wet air volume flow under the actual working condition into dry air volume flow under the same temperature and the same pressure according to the actual test working condition parameters;
and converting the dry air volume flow under the same temperature and pressure as the actual working condition into the dry air volume flow in the measured channel under the specific temperature and the specific pressure in the design working condition.
The following provides several alternatives, but not as additional limitations to the above-described overall scheme, and only further additions or preferences, each of which may be individually combined for the above-described overall scheme, or may be combined among multiple alternatives, without technical or logical contradictions.
Preferably, the actual test condition parameters include a wet air temperature, a wet air relative humidity, a wet air pressure value and a pressure difference between two ends of a nozzle of the volumetric flowmeter in the wind measurement box under the actual condition, and the method converts the wet air volumetric flow under the actual condition into a dry air volumetric flow under the same temperature and the same pressure according to the actual test condition parameters, and includes:
calculating the wet air volume flow at the plane of the volume flowmeter by using a gas flow formula;
calculating the amount of the substances of the water vapor and the dry air contained in the wet air under the actual working condition;
calculating the mass of water vapor contained in the wet air and the mass of the dry air under the actual working condition;
and converting the water vapor in the wet air under the actual working condition into dry air with the same mass, and converting the dry air volume flow under the same temperature and the same pressure based on the wet air volume flow.
Preferably, the gas flow formula is as follows:
in which Q v1 For the wet air volume flow at the nozzle of the volumetric flowmeter under the actual working condition, C is the nozzle flow coefficient of the volumetric flowmeter, beta is the diameter ratio of the nozzle of the volumetric flowmeter, epsilon is the expansibility coefficient, d is the orifice or throat diameter of the throttling element under the working condition of the volumetric flowmeter, deltap is the pressure difference at the two ends of the nozzle of the volumetric flowmeter, and rho a1 For the fluid density at temperature and pressure when measuring volume flow under actual conditions, the fluid density ρ a1 The formula of (2) is as follows:
wherein p is 1 Is the wet air pressure value under the actual working condition, p V To the partial pressure of water vapor in the wet air under the actual working condition, p V ＝ψp b Psi is the relative humidity of the wet air under the actual working condition, p b Saturated vapor pressure, Θ is the absolute temperature of air under design conditions.
Preferably, the calculating the amount of the water vapor contained in the wet air and the amount of the dry air under the actual condition, calculates the mass of the water vapor contained in the wet air and the mass of the dry air under the actual condition, includes:
the wet air is used as the mixed gas of the dry air and the water vapor, and the mass of the water vapor in the wet air under the actual working condition is obtained as follows:
wherein n is V For the amount of the water vapor in the wet air under the actual working condition, p V To the partial pressure of water vapor in the wet air under the actual working condition, p V ＝ψp b Psi is the relative humidity of the wet air under the actual working condition, p b Is saturated steam pressure, V is the gas volume of wet air in the wind measuring box, R is universal gas constant, T k Is the absolute temperature of the wet air under the actual working condition, T k ＝T 1 +273.15，T 1 The wet air temperature under the actual working condition;
the amount of dry air in the wet air under actual conditions was calculated as follows:
wherein n is a To the amount of dry air matters in the wet air under the actual working condition, p a To the partial pressure of dry air in wet air under the actual working condition, p 1 The wet air pressure value is the wet air pressure value under the actual working condition;
the mass of water vapor in the wet air under the actual working condition is calculated as follows:
m V ＝n V M V
wherein m is V For the quality of water vapor in the wet air under the actual working condition, M V Is the molar mass of the water vapor;
the mass of dry air in wet air under actual working conditions is calculated as follows:
m a ＝n a M a
wherein m is a M is the mass of dry air in wet air under actual working conditions a Is the molar mass of dry air.
Preferably, the converting the water vapor in the wet air under the actual working condition into dry air with the same mass, and converting the dry air volume flow under the same temperature and same pressure based on the wet air volume flow includes:
in which Q a1 For dry air volume flow at the same temperature and pressure as the actual working condition, m V For the mass of the water vapor in the wet air under the actual working condition, m a M is the mass of dry air in wet air under actual working conditions V M is the molar mass of the water vapor a Molar mass of dry air, Q v1 Is the wet air volume flow at the nozzle of the volumetric flowmeter under actual working conditions.
Preferably, the converting the dry air volume flow under the same temperature and pressure as the actual working condition into the dry air volume flow in the measured channel under the specific temperature and the specific pressure in the designed working condition includes:
from conservation of mass, it is possible to obtain:
the following conversion relation exists between the fluid densities:
the dry air volume flow in the tested channel under the specific temperature and the specific pressure in the design working condition is obtained:
in which Q a1 To dry air volume flow at the same temperature and the same pressure as the actual working condition, Q a2 For designing the dry air volume flow rate in the tested channel under the specific temperature and the specific pressure in the working condition, ρ a1 For the density of the fluid at the temperature and pressure when the volume flow is measured under the actual working condition ρ a2 To design the fluid density in the working condition, T 1 To the wet air temperature under the actual working condition, p 1 Is the wet air pressure value under the actual working condition, T 2 To design the air temperature under working condition, p 2 For the air pressure value under the design working condition, m V For the mass of the water vapor in the wet air under the actual working condition, m a Is wet under actual working conditionsMass of dry air in air, M V M is the molar mass of the water vapor a Molar mass of dry air, Q v1 Is the wet air volume flow at the nozzle of the volumetric flowmeter under actual working conditions.
Preferably, a baffle plate is arranged in the middle of the air volume measuring box, flow homogenizing plates are arranged on two sides of the baffle plate, the baffle plate and the flow homogenizing plates are parallel to the cross section of the air volume measuring box, the center of the baffle plate is open and connected with a volume flowmeter, a differential pressure transmitter is arranged at a nozzle of the volume flowmeter, and a hygrothermograph and a pressure sensor are arranged on the baffle plate.
Compared with the prior art, the gas volume flow conversion method for measuring the air resistance of the heat exchanger in the open environment has the following beneficial effects:
(1) The invention is suitable for detecting the air resistance of the heat exchanger in an open non-standard environment, and reduces the difficulty and cost of detecting the air resistance of the heat exchanger.
(2) The method realizes a related formula of conversion between the volume flow of the non-standard condition environmental gas and the volume flow of the standard condition environmental gas in the open environment, provides a basis for judging the qualification of the non-standard condition by utilizing the air resistance value of the non-standard condition heat exchanger, and can obtain a more accurate air resistance measurement result.
Drawings
FIG. 1 is a flow chart of a method for converting gas volume flow into heat exchanger air lock measurements in an open environment according to the present invention;
FIG. 2 is a schematic view of the structure of the wind-measuring box of the present invention.
In the drawings: 1. a channel to be tested; 2. a heat exchanger; 3. a connecting pipe; 4. a wind volume measuring box; 5. a flow homogenizing plate; 6. a nozzle of a volumetric flow meter.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Unless defined otherwise, all 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. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
In order to overcome the defects of the prior art, the embodiment provides a gas volume flow conversion method for measuring the gas resistance of a heat exchanger in an open environment. As shown in fig. 1, the conversion process is in two stages: (1) The dehumidification treatment of the wet air under the actual working condition, namely, the water vapor in the wet air is replaced by dry air with the same mass based on mass conservation, and the volume flow of the converted dry air under the same temperature and the same pressure is obtained; (2) And converting the dry air volume flow under the actual working condition to the design working condition, namely converting the dry air volume flow of the actual temperature and the actual pressure into the dry air volume flow in the measured channel under the temperature and the pressure required by the design working condition.
As shown in fig. 2, the embodiment provides a wind volume measuring box 5 connected with a measured channel 1 in a heat exchanger 2, the two are connected through a connecting pipe 3, a baffle plate (a plane P1 is provided) is installed in the middle part in the wind volume measuring box 4, a flow homogenizing plate 5 is installed on two sides of the baffle plate, the baffle plate and the flow homogenizing plate 5 are parallel to the cross section of the wind volume measuring box, namely, the flow homogenizing plate is perpendicular to the wind flow direction, an opening is formed in the center of the baffle plate, a volumetric flowmeter is connected with the opening of the nozzle 6 of the volumetric flowmeter, a differential pressure transmitter is installed on the baffle plate, and a hygrothermograph and a pressure sensor are installed on any position of the baffle plate.
Stage one: and converting the wet air volume flow under the actual working condition into the dry air volume flow under the same temperature and the same pressure.
The known condition is that the high-precision hygrothermograph and the pressure sensor arranged on the plane P1 of the air volume measuring box measure the air temperature T under the actual measuring environment 1 Relative humidity ψ and pressure value p 1 As well as both the geometry (diameter d) of the nozzle in the wind measuring box and the nozzle obtained by the differential pressure transmitterDifferential pressure Δp at the ends.
First, a temperature T is calculated 1 Pressure value p 1 Fluid density ρ of humid air at relative humidity ψ a1 Then, the gas volume flow Q of the wet air is calculated by using a nozzle gas volume flow calculation formula and bringing the pressure difference delta p at two ends of the nozzle and the diameter d of the nozzle v1 The following are provided:
wherein: q (Q) v1 For the wet air volume flow at the nozzle of the volume flowmeter under the actual working condition, m 3 /s。
C is the nozzle flow coefficient of the volumetric flowmeter, and is provided by the nozzle manufacturer.
d is the orifice or throat diameter of the orifice member under volumetric flow meter operating conditions, m.
Epsilon is the coefficient of expansion and is generally approximately 1.
Δp is the pressure differential across the nozzle of the volumetric flow meter, pa.
Beta is the diameter ratio of the nozzles of the volumetric flowmeter,in this example, the long-diameter low-ratio nozzle can take 1-beta 4 ≈1。
ρ a1 For measuring fluid density at temperature and pressure at volume flow under actual conditions, kg/m 3 . The wet air fluid density under actual conditions can be found according to formula (2):
wherein: Θ is the absolute temperature of air under the design working condition, K.
p V To the partial pressure of water vapor in the wet air under the actual working condition, p V ＝ψp b Psi is the relative humidity,%, p of the wet air under the actual working condition b Is saturated with water vaporThe pressure, pa, and the value can be obtained by looking up a correlation table.
p 1 And Pa is the wet air pressure value under the actual working condition.
Next, the temperature T is calculated 1 Pressure p 1 The mass of the water vapor contained in the humid air at the relative humidity psi is replaced by the dry air of the same mass, and then the gas volume flow Q of the converted dry air is calculated a1 。
(1) The amounts of water vapor and dry air substances contained in the wet air under actual conditions are calculated.
Wet air is considered as a mixture of dry air and water vapor, wherein the partial pressure p of water vapor V ＝ψp b The amount of water vapor:
wherein: n is n V Is the amount of the substance of the water vapor in the wet air under the actual working condition.
R is universal gas constant, R=8.31 J.mol -1 ·K -1 。
V is the gas volume of the humid air in the wind measuring box, m 3 。
T k Is the absolute temperature of the wet air under the actual working condition, T k ＝T 1 +273.15，T 1 Is the temperature of the wet air under the actual working condition.
The amount of dry air material in the wet air was calculated:
wherein: n is n a Is the amount of dry air in the wet air under actual conditions.
p a And Pa is the partial pressure of dry air in wet air under actual working conditions.
(2) The mass of water vapor and air contained in the humid air was calculated separately.
Mass m of water vapor contained in humid air V The method comprises the following steps:
m V ＝n V M V (5)
wherein: m is M V M is the molar mass of the water vapor V ＝18k·mol -1 。
Mass m of dry air contained in humid air a The method comprises the following steps:
m a ＝n a M a (6)
wherein: m is M a Molar mass of dry air, M a ＝29k·mol -1 。
(3) The water vapor is replaced by dry air with the same mass, and the gas volume flow Q of the converted dry air is calculated a1 。
After the water vapor is replaced by the dry air, the gas volume flow of the converted dry air is calculated according to the formula (7)
Stage two: the dry air volume flow Q at the plane P1 under the actual working condition a1 Converted into the dry air volume flow Q flowing at the plane P2 of the specific measuring channel 1 of the heat exchanger 2 under design conditions a2 。
The known condition is the working temperature T under the actual working condition 1 Pressure value p 1 Measured temperature T required by design conditions 2 Pressure value p 2 . The specific conversion process is as follows:
based on the conservation of the mass flow of the gas in the measurement channel, the actual working temperature T can be calculated by utilizing the state equation of the ideal gas 1 Pressure value p 1 Dry air volume flow Q a1 Converting into measured temperature T required for design conditions 2 Pressure value p 2 Dry air volume flow Q at the time a2 。
From conservation of mass, it is possible to obtain:
the following conversion relation exists between the fluid densities:
bringing equation (9) into equation (8) yields a volumetric flow rate at plane P2:
wherein: q (Q) a2 For designing the dry air volume flow in the tested channel under the specific temperature and the specific pressure in the working condition, m 3 /s。
ρ a2 Kg/m for the fluid density in the design regime 3 。
T 2 Is the temperature of the air under the design working condition, and is in the DEG C.
p 2 And Pa is the air pressure value under the design working condition.
After the above conversion, the flow rate Q a2 And design measured temperature T 2 Pressure value p 2 Accurate matching is realized, and the measured air resistance value is more accurate and reliable.
The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The above examples merely represent a few embodiments of the present invention, which are described in more detail and are not to be construed as limiting the scope of the invention. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of the invention should be assessed as that of the appended claims.
Claims (7)
1. The utility model provides a gas volume flow conversion method of heat exchanger air resistance measurement under open environment for to the dry air volume flow measurement in the measured passageway under the design operating mode, its characterized in that, the measured passageway is connected with the amount of wind measurement case through the connecting pipe, heat exchanger air resistance measurement's gas volume flow conversion method under open environment includes:
acquiring actual test working condition parameters based on an air volume measuring box, and converting wet air volume flow under the actual working condition into dry air volume flow under the same temperature and the same pressure according to the actual test working condition parameters;
and converting the dry air volume flow under the same temperature and pressure as the actual working condition into the dry air volume flow in the measured channel under the specific temperature and the specific pressure in the design working condition.
2. The method for converting the volumetric flow rate of gas measured by the air resistance of the heat exchanger in the open environment according to claim 1, wherein the actual test condition parameters include the temperature of the wet air, the relative humidity of the wet air, the pressure value of the wet air and the pressure difference between two ends of the nozzle of the volumetric flow meter in the wind measuring box under the actual condition, and the method for converting the volumetric flow rate of the wet air under the actual condition into the volumetric flow rate of the dry air under the same temperature and the same pressure according to the actual test condition parameters comprises:
calculating the wet air volume flow at the plane of the volume flowmeter by using a gas flow formula;
calculating the amount of the substances of the water vapor and the dry air contained in the wet air under the actual working condition;
calculating the mass of water vapor contained in the wet air and the mass of the dry air under the actual working condition;
and converting the water vapor in the wet air under the actual working condition into dry air with the same mass, and converting the dry air volume flow under the same temperature and the same pressure based on the wet air volume flow.
3. The method for converting gas volume flow into heat exchanger air lock measurement in open environment according to claim 2, wherein the gas flow formula is as follows:
in which Q v1 For the wet air volume flow at the nozzle of the volumetric flowmeter under the actual working condition, C is the nozzle flow coefficient of the volumetric flowmeter, beta is the diameter ratio of the nozzle of the volumetric flowmeter, epsilon is the expansibility coefficient, d is the orifice or throat diameter of the throttling element under the working condition of the volumetric flowmeter, deltap is the pressure difference at the two ends of the nozzle of the volumetric flowmeter, and rho a1 For the fluid density at temperature and pressure when measuring volume flow under actual conditions, the fluid density ρ a1 The formula of (2) is as follows:
wherein p is 1 Is the wet air pressure value under the actual working condition, p V To the partial pressure of water vapor in the wet air under the actual working condition, p V ＝ψp b Psi is the relative humidity of the wet air under the actual working condition, p b Saturated vapor pressure, Θ is the absolute temperature of air under design conditions.
4. The method for converting the volumetric flow rate of gas measured by the air resistance of a heat exchanger in an open environment according to claim 2, wherein the calculating the amount of the water vapor contained in the wet air and the amount of the dry air in the actual condition, and the calculating the mass of the water vapor contained in the wet air and the mass of the dry air in the actual condition, comprises:
the wet air is used as the mixed gas of the dry air and the water vapor, and the mass of the water vapor in the wet air under the actual working condition is obtained as follows:
wherein n is V For the amount of the water vapor in the wet air under the actual working condition, p V To the partial pressure of water vapor in the wet air under the actual working condition, p V ＝ψp b Psi is the relative humidity of the wet air under the actual working condition, p b Is saturated steam pressure, V is the gas volume of wet air in the wind measuring box, R is universal gas constant, T k Is the absolute temperature of the wet air under the actual working condition, T k ＝T 1 +273.15，T 1 The wet air temperature under the actual working condition;
the amount of dry air in the wet air under actual conditions was calculated as follows:
wherein n is a To the amount of dry air matters in the wet air under the actual working condition, p a To the partial pressure of dry air in wet air under the actual working condition, p 1 The wet air pressure value is the wet air pressure value under the actual working condition;
the mass of water vapor in the wet air under the actual working condition is calculated as follows:
m V ＝n V M V
wherein m is V For the quality of water vapor in the wet air under the actual working condition, M V Is the molar mass of the water vapor;
the mass of dry air in wet air under actual working conditions is calculated as follows:
m a ＝n a M a
wherein m is a M is the mass of dry air in wet air under actual working conditions a Is the molar mass of dry air.
5. The method for converting the volumetric flow rate of gas measured by the air resistance of the heat exchanger in the open environment according to claim 2, wherein the step of converting the water vapor in the wet air under the actual condition into the dry air with the same mass and obtaining the volumetric flow rate of the dry air under the same temperature and the same pressure based on the volumetric flow rate of the wet air comprises the following steps:
in which Q a1 For dry air volume flow at the same temperature and pressure as the actual working condition, m V For the mass of the water vapor in the wet air under the actual working condition, m a M is the mass of dry air in wet air under actual working conditions V M is the molar mass of the water vapor a Molar mass of dry air, Q v1 Is the wet air volume flow at the nozzle of the volumetric flowmeter under actual working conditions.
6. The method for converting the volumetric flow rate of the gas in the open environment heat exchanger according to claim 1, wherein the step of converting the volumetric flow rate of the dry air at the same temperature and the same pressure as the actual condition into the volumetric flow rate of the dry air in the measured channel at the specific temperature and the specific pressure in the designed condition comprises the steps of:
from conservation of mass, it is possible to obtain:
the following conversion relation exists between the fluid densities:
the dry air volume flow in the tested channel under the specific temperature and the specific pressure in the design working condition is obtained:
in which Q a1 To dry air volume flow at the same temperature and the same pressure as the actual working condition, Q a2 For designing the dry air volume flow rate in the tested channel under the specific temperature and the specific pressure in the working condition, ρ a1 For the density of the fluid at the temperature and pressure when the volume flow is measured under the actual working condition ρ a2 To design the fluid density in the working condition, T 1 To the wet air temperature under the actual working condition, p 1 Is the wet air pressure value under the actual working condition, T 2 To design the air temperature under working condition, p 2 For the air pressure value under the design working condition, m V For the mass of the water vapor in the wet air under the actual working condition, m a M is the mass of dry air in wet air under actual working conditions V M is the molar mass of the water vapor a Molar mass of dry air, Q v1 Is the wet air volume flow at the nozzle of the volumetric flowmeter under actual working conditions.
7. The method for converting the volumetric flow rate of gas measured by the air resistance of the heat exchanger under the open environment according to claim 1, wherein a baffle is arranged in the middle of the air flow measuring box, flow homogenizing plates are arranged on two sides of the air flow measuring box, the baffle and the flow homogenizing plates are parallel to the cross section of the air flow measuring box, an opening is formed in the center of the baffle and connected with a volumetric flowmeter, a differential pressure transmitter is arranged at a nozzle of the volumetric flowmeter, and a hygrothermograph and a pressure sensor are arranged on the baffle.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311602807.8A CN117633404A (en) | 2023-11-28 | 2023-11-28 | Gas volume flow conversion method for heat exchanger air resistance measurement in open environment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311602807.8A CN117633404A (en) | 2023-11-28 | 2023-11-28 | Gas volume flow conversion method for heat exchanger air resistance measurement in open environment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117633404A true CN117633404A (en) | 2024-03-01 |
Family
ID=90015794
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311602807.8A Pending CN117633404A (en) | 2023-11-28 | 2023-11-28 | Gas volume flow conversion method for heat exchanger air resistance measurement in open environment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117633404A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118051071A (en) * | 2024-04-15 | 2024-05-17 | 苏芯物联技术(南京)有限公司 | Adjustable gas flow measurement and control device and method |
-
2023
- 2023-11-28 CN CN202311602807.8A patent/CN117633404A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN118051071A (en) * | 2024-04-15 | 2024-05-17 | 苏芯物联技术(南京)有限公司 | Adjustable gas flow measurement and control device and method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN117633404A (en) | Gas volume flow conversion method for heat exchanger air resistance measurement in open environment | |
| CN105606786B (en) | Method and measuring device for determining a specific quantity of a gas quality | |
| CN203837782U (en) | Diaphragm gas meter metering performance isothermal calibrating apparatus under conditions of limiting temperature | |
| CN110726444B (en) | Wet gas flow metering method and device based on Coriolis mass flowmeter | |
| CN107830914A (en) | The micrometeor calibrating installation and method of a kind of binary channels symmetrical structure | |
| CN116398421A (en) | High vacuum pump pumping speed testing device and using method thereof | |
| CN210036908U (en) | High-pressure natural gas flow primary standard device with adjustable sonic nozzle | |
| CN111103020B (en) | Flow detection device, flow control system and flow detection method | |
| CN111735635A (en) | Cold flow backpressure test bench and cold flow backpressure test method of post-processor | |
| CN105784926B (en) | High wet gas current water capacity measurement apparatus and method | |
| Wright et al. | Gas flowmeter calibrations with the 34 L and 677 L PVTt standards | |
| Hajilouy-Benisi et al. | Empirical assessment of the performance characteristics in turbocharger turbine and compressor | |
| CN205388506U (en) | Circulating high -pressure gas flow rate standard facility | |
| CN113587976B (en) | Wide temperature range air temperature humidity sampling measurement device | |
| CN216349016U (en) | Flow calibrating device and flow calibrating system | |
| CN111677683B (en) | Method and device for testing pneumatic performance of micro fan based on flow compensation method | |
| CN112683564B (en) | Method for calculating rated refrigerating capacity deviation of air conditioner at different wind speeds | |
| Guillou | Uncertainty and measurement sensitivity of turbocharger compressor gas stands | |
| CN114046861A (en) | Method for improving dynamic flow measurement accuracy of differential pressure type flowmeter | |
| Wright | The long term calibration stability of critical flow nozzles and laminar flowmeters | |
| Wettstein et al. | Design and validation of the MBW standard humidity generators | |
| KR20120041291A (en) | Device and method for calibrating discharge coefficients of sonic nozzles using constant volume flow-meter | |
| CN201532347U (en) | Rupture disk flow resistance coefficient testing system | |
| CN111503628B (en) | Method for measuring gas boiler flue gas recirculation rate | |
| CN216385920U (en) | Flow calibrating device and flow calibrating system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |