Flow coefficient correction method for switching measurement of parallel flowmeter group

Abstract

The embodiment of the present disclosure provides a flow coefficient correction method for switching measurement of a parallel flowmeter group. The method comprises: taking the parallel flowmeter group as a to-be-corrected flowmeter of an experimental piece and setting a reference flowmeter of the experimental piece; determining a first measurement value of an adiabatic index related function corresponding to the reference flowmeter and a second measurement value of the adiabatic index related function corresponding to the to-be-corrected flowmeter; taking the ratio of the first measurement value and the second measurement value as a flow correction coefficient; determining the number of flowmeters in the parallel flowmeter group, and determining a sub-flow correction coefficient corresponding to each flowmeter according to the number of flowmeters and the flow correction coefficient; and correcting the flow coefficient of each flowmeter through the sub-flow correction coefficient, so as to realize the flow coefficient correction of the parallel flowmeter group. The determination of the sub-flow correction coefficient of each flowmeter can realize the smooth transition of the flow measurement of the parallel flowmeter group and ensure the correction accuracy. The flow coefficient correction method has low requirements on experimental measurement conditions, and reduces the time cost and economic cost.

Description

A method for correcting the flow coefficient in parallel flow meter group switching measurement Technical Field

[0001] This invention relates to the field of flow measurement, and in particular to a method, apparatus, and equipment for correcting the flow coefficient in parallel flow meter group switching measurement. Background Technology

[0002] In experimental measurement research, high-precision parameter measurement is an important guarantee for ensuring the accuracy of experimental results. The instrument for measuring flow rate is called a flow meter, and the combination of multiple flow meters is called a flow meter group. Usually, flow meters with different ranges and types have different accuracy levels. In experiments, it is inevitable to encounter problems where the working fluid flow rate varies greatly, and a single flow meter cannot meet the measurement range of all working fluid flow rates. Usually, multiple flow meters with different ranges or different models can be combined in parallel or series to switch between measurements, thereby meeting the measurement needs of different mass flow rate ranges in experiments.

[0003] To address the issue of varying accuracy levels among flowmeters of different operating ranges and types when using parallel flowmeter arrays to measure mass flow rate, existing technologies calibrate each flowmeter individually before use to ensure the measurement accuracy and range of the working fluid mass flow rate in experiments, thereby improving the measurement accuracy of each flowmeter.

[0004] Existing technologies cause discontinuities in the mass flow measurement characteristic curve when switching flow meters, making it impossible to ensure a smooth transition of the mass flow measurement characteristic curve during flow meter switching. Summary of the Invention

[0005] The purpose of this invention is to overcome the problem that the mass flow characteristic lines of each flowmeter in a parallel flowmeter group cannot transition continuously during the switching measurement process. This invention provides a method, device, and equipment for correcting the flow coefficient of a parallel flowmeter group. By correcting the flow coefficient of the parallel flowmeter group, the mass flow measurement can be smoothly transitioned when switching flowmeters.

[0006] In a first aspect, embodiments of this disclosure provide a method for correcting the flow coefficient during switching measurements of a parallel flow meter group, the method comprising:

[0007] S1: Use the parallel flow meter group as the flow meter to be corrected in the test piece and set the reference flow meter for the test piece;

[0008] S2: Determine the first measured value of the adiabatic index correlation function corresponding to the reference flowmeter and the second measured value of the adiabatic index correlation function corresponding to the flowmeter to be corrected;

[0009] S3: Use the ratio of the first measurement value and the second measurement value as the flow correction coefficient;

[0010] S4: Determine the number of flow meters in the parallel flow meter group, and determine the sub-flow correction coefficient for each flow meter based on the number of flow meters and the flow correction coefficient;

[0011] S5: The flow coefficient of each flow meter is corrected by the sub-flow correction coefficient to achieve the flow coefficient correction of the parallel flow meter group.

[0012] Optionally, step S2 specifically includes:

[0013] S21: Measure the first actual mass flow rate of the test piece using a reference flow meter, and measure the second actual mass flow rate of the test piece using a flow meter to be corrected;

[0014] S22: Define the adiabatic index related function;

[0015] S23: Determine the first and second measured values ​​based on the first actual mass flow rate, the second actual mass flow rate, and the adiabatic index correlation function.

[0016] Optionally, the actual mass flow rate in step S21 is expressed as:

[0017]

[0018] in, C represents the actual mass flow rate of the experimental specimen. D Indicates the flow coefficient of the experimental specimen. p0 represents the ideal mass flow rate of the experimental specimen. * R represents the total inlet pressure of the test specimen, A represents the outlet area of ​​the test specimen, and R represents the total inlet pressure of the test specimen. g T0 represents the gas constant. * The total inlet temperature of the experimental specimen is represented by π, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

[0019] Optionally, the adiabatic index correlation function defined in step S22 is:

[0020]

[0021] Among them, F T represents the adiabatic index correlation function, and k represents the isentropic index.

[0022] Optionally, the principle for calculating the measured value in step S23 is as follows:

[0023]

[0024] Among them, F T,ME Indicates the measured value. R represents the actual mass flow rate of the experimental specimen. g T0 represents the gas constant. * The total inlet temperature of the test specimen is represented by C. D p0 represents the flow coefficient of the experimental specimen, A represents the outlet area of ​​the experimental specimen, and p0 represents the flow coefficient of the experimental specimen. * π represents the total inlet pressure of the experimental specimen, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

[0025] Optionally, the flow correction factor in step S3 is expressed as:

[0026]

[0027] Among them, F T,ME The values ​​represent the measured values. The subscript R indicates the first measured value from the reference flowmeter, and the subscript C indicates the second measured value from the flowmeter to be corrected. R represents the actual mass flow rate of the experimental specimen. g T0 represents the gas constant. * The total inlet temperature of the test specimen is represented by C. D p0 represents the flow coefficient of the experimental specimen, A represents the outlet area of ​​the experimental specimen, and p0 represents the flow coefficient of the experimental specimen. * π represents the total inlet pressure of the experimental specimen, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

[0028] Optionally, step S4 specifically includes:

[0029] S41: Determine the sum of squares of deviations of the parallel flow meter group and the relationship of correction coefficients between two adjacent flow meters based on the number of flow meters; S42: Determine the correction coefficients for each sub-flow rate based on the sum of squares of deviations and the relationship of correction coefficients.

[0030] Secondly, embodiments of this disclosure also provide a flow coefficient correction device for switching measurements of parallel flowmeter groups, the device comprising:

[0031] The flow meter setting module is used to use a parallel flow meter group as the flow meter to be corrected in the test piece and to set the reference flow meter in the test piece;

[0032] The measurement value determination module is used to determine the first measured value of the adiabatic index correlation function corresponding to the reference flow meter and the second measured value of the adiabatic index correlation function corresponding to the flow meter to be corrected.

[0033] The flow correction coefficient determination module is used to use the ratio of the first measurement value and the second measurement value as the flow correction coefficient.

[0034] The sub-flow correction coefficient determination module is used to determine the sub-flow correction coefficient for each flow meter based on the number of flow meters and the flow correction coefficient in a parallel flow meter group.

[0035] The flow coefficient correction module is used to correct the flow coefficient of each flow meter through the sub-flow correction coefficient, so as to realize the flow coefficient correction of the parallel flow meter group.

[0036] Thirdly, embodiments of this disclosure also provide an electronic device, the electronic device comprising:

[0037] At least one processor; and

[0038] A memory communicatively connected to at least one processor; wherein, when the memory stores a computer program executable by at least one processor, the computer program is executed by at least one processor to enable at least one processor to perform a flow coefficient correction method for switching measurements of a parallel flow meter group as described in any embodiment of this disclosure.

[0039] Fourthly, embodiments of this disclosure provide a computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements a method for correcting the flow coefficient of a parallel flow meter group switching measurement as described in any embodiment of this disclosure.

[0040] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description.

[0041] Therefore, the present invention has the following beneficial effects:

[0042] 1. An adiabatic index correlation function was defined as a reference for correction, ensuring the accuracy of the correction.

[0043] 2. Determining the sub-flow correction factor for each flowmeter allows for a smooth transition in flow measurement across a parallel flowmeter group.

[0044] 3. The flow coefficient correction method has low requirements for experimental measurement conditions, reducing time and economic costs. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 is a flowchart of a flow coefficient correction method for switching measurements of parallel flowmeter groups according to Embodiment 1 of the present invention;

[0047] Figure 2 is a flowchart of another method for correcting the flow coefficient of a parallel flow meter group switching measurement according to Embodiment 1 of the present invention;

[0048] Figure 3 is a flowchart of another method for correcting the flow coefficient of a parallel flow meter group switching measurement according to Embodiment 1 of the present invention;

[0049] Figure 4 is a schematic diagram of an experimental platform structure provided according to Embodiment 2 of the present invention;

[0050] Figure 5 is a schematic diagram of the structure of an experimental helical tooth provided according to Embodiment 2 of the present invention;

[0051] Figure 6 is a schematic diagram of the characteristic curve of the flow coefficient before correction as a function of pressure ratio according to Embodiment 2 of the present invention;

[0052] Figure 7 is a schematic diagram of the characteristic curve of the corrected flow coefficient as a function of pressure ratio according to Embodiment 2 of the present invention;

[0053] Figure 8 is a schematic diagram of a flow coefficient correction device for switching measurement of parallel flowmeter groups according to Embodiment 3 of the present invention;

[0054] Figure 9 is a schematic diagram of the structure of an electronic device provided according to Embodiment 4 of the present invention.

[0055] The components are: 1. Experimental table inlet; 2. Air inlet section; 3. Contraction tube section; 4. Flanged experimental section; 5. Oral cavity section; 6. Experimental table outlet. Detailed Implementation

[0056] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0057] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0058] Example 1

[0059] Figure 1 is a flowchart of a flow coefficient correction method for switching measurements using a parallel flow meter group, provided in Embodiment 1 of the present invention. This embodiment is applicable to situations where a parallel flow meter group is used to measure experimental specimens. This method can be executed by the flow coefficient correction device for the parallel flow meter group provided in this disclosure embodiment. This device can be implemented in software and / or hardware, and is generally integrated into a computer device. The method of this disclosure embodiment specifically includes:

[0060] S1: Use the parallel flow meter group as the flow meter to be corrected in the test piece and set the reference flow meter for the test piece.

[0061] In this context, a flow meter refers to an instrument that measures flow rate. Flow meters can be categorized into orifice plate flow meters, venturi flow meters, turbine flow meters, vortex flow meters, target flow meters, rotor flow meters, volumetric flow meters, ultrasonic flow meters, etc. A flow meter group refers to a combination of multiple flow meters. In this embodiment, it mainly refers to switching between flow meters with different ranges or models by connecting them in parallel. A reference flow meter refers to a standard flow meter operating under the same experimental conditions as the parallel flow meter group. It should be noted that this embodiment uses an orifice plate flow meter as an example and does not limit the range or model of the flow meter. An orifice plate flow meter is a high-range differential pressure flow device composed of a standard orifice plate and a multi-parameter differential pressure transmitter (or a differential pressure transmitter, temperature transmitter, and pressure transmitter), capable of measuring the flow rate of gases, steam, liquids, and other substances.

[0062] S2: Determine the first measured value of the adiabatic index correlation function corresponding to the reference flowmeter and the second measured value of the adiabatic index correlation function corresponding to the flowmeter to be corrected.

[0063] Figure 2 is a flowchart of a flow coefficient correction method for switching measurements of parallel flowmeter groups provided in Embodiment 1 of the present invention. Step S2 mainly includes the following steps S21 to S23:

[0064] S21: Measure the first actual mass flow rate of the test piece using a reference flow meter, and measure the second actual mass flow rate of the test piece using a flow meter to be corrected.

[0065] Optionally, the actual mass flow rate in step S21 is expressed as:

[0066]

[0067] in, C represents the actual mass flow rate of the experimental specimen. D Indicates the flow coefficient of the experimental specimen. p0 represents the ideal mass flow rate of the experimental specimen. * R represents the total inlet pressure of the test specimen, A represents the outlet area of ​​the test specimen, and R represents the total inlet pressure of the test specimen. g T0 represents the gas constant. * The total inlet temperature of the experimental specimen is represented by π, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

[0068] Specifically, the flow coefficient C of the experimental specimen D It can be represented as:

[0069]

[0070] Among them, C D Indicates the flow coefficient of the experimental specimen. This represents the actual mass flow rate of the experimental specimen. This represents the ideal mass flow rate of the experimental specimen.

[0071] Specifically, the ideal mass flow rate of the experimental specimen is derived from the measured inlet and outlet pressures and temperature parameters of the flow meter according to the isentropic relationship, that is, the ideal mass flow rate is:

[0072]

[0073] in, p0 represents the ideal mass flow rate of the experimental specimen. * R represents the total inlet pressure of the test specimen, A represents the outlet area of ​​the test specimen, and R represents the total inlet pressure of the test specimen. g T0 represents the gas constant. * The total inlet temperature of the experimental specimen is represented by π, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

[0074] S22: Define the adiabatic index correlation function.

[0075] Specifically, as shown in equation (1), for any experimental piece, when the total inlet temperature T0 * Import total pressure p0 *When the pressure ratio π is constant, the flow coefficient C D It is a definite value, flow rate It is also a unique value, that is, it satisfies and Considering that the measurement conditions of the reference flowmeter and the flowmeter to be corrected are unlikely to be exactly the same, changes in inlet pressure, temperature, and pressure ratio during the measurement process will all lead to changes in the measured mass flow rate. To ensure correction accuracy, a constant physical quantity needs to be defined as the reference for correction. In this embodiment, a function that is only related to the adiabatic index (temperature) is defined.

[0076] Optionally, the adiabatic index correlation function defined in step S22 is:

[0077]

[0078] Among them, F T represents the adiabatic index correlation function, and k represents the isentropic index.

[0079] S23: Determine the first and second measured values ​​based on the first actual mass flow rate, the second actual mass flow rate, and the adiabatic index correlation function.

[0080] Specifically, as shown in equation (4), when the inlet temperature remains constant, the adiabatic index correlation function is a constant. The measured value of the adiabatic index correlation function can be calculated according to equation (1).

[0081] Optionally, the principle for calculating the measured value in step S23 is as follows:

[0082]

[0083] Among them, F T,ME Indicates the measured value. R represents the actual mass flow rate of the experimental specimen. g T0 represents the gas constant. * The total inlet temperature of the test specimen is represented by C. D p0 represents the flow coefficient of the experimental specimen, A represents the outlet area of ​​the experimental specimen, and p0 represents the flow coefficient of the experimental specimen. * π represents the total inlet pressure of the experimental specimen, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

[0084] S3: Use the ratio of the first measurement value and the second measurement value as the flow correction factor.

[0085] Specifically, under the condition that the inlet temperature remains constant and the measuring instrument has no measurement error, the measured value is a constant and is independent of the measurement conditions. Considering that there is measurement error in the experimental measurement process, the correction coefficient ζ is defined as the ratio of the measured values ​​of the reference flowmeter and the flowmeter to be corrected.

[0086] Optionally, the flow correction factor in step S3 is expressed as:

[0087]

[0088] Among them, F T,ME The values ​​represent the measured values. The subscript R indicates the first measured value from the reference flowmeter, and the subscript C indicates the second measured value from the flowmeter to be corrected. R represents the actual mass flow rate of the experimental specimen. g T0 represents the gas constant. * The total inlet temperature of the test specimen is represented by C. D p0 represents the flow coefficient of the experimental specimen, A represents the outlet area of ​​the experimental specimen, and p0 represents the flow coefficient of the experimental specimen. * π represents the total inlet pressure of the experimental specimen, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

[0089] Specifically, in equation (6), the outlet area A and pressure Temperature T0 * Pressure ratio π and mass flow rate All are measured parameters, and CD in the formula are unknown parameters. Any set of working conditions can be denoted as: Abbreviated as According to Taylor's theorem, for any working condition In its neighborhood U δ Any working condition within (OP1)(δ>0) Its corresponding flow coefficient CD can be expressed as C D (OP) = C D (OP1)+C′ D (OP1)(OP-OP1)+O(OP-OP1), when δ is sufficiently small, the infinitesimals of the same and higher orders of OP-OP1 are not considered, and CD(OP) is approximately considered to be CD(OP1). Since the outlet area A of the experimental piece is constant, equation (6) can be expressed as:

[0090]

[0091] in, T0 represents the actual mass flow rate of the experimental specimen. * p0 represents the total inlet temperature of the experimental specimen. * The total inlet pressure of the test specimen is represented by π, k represents the isentropic exponent, π represents the pressure ratio of the test specimen, the subscript R represents the corresponding value of the reference flowmeter, and the subscript C represents the corresponding value of the flowmeter to be corrected.

[0092] In the above formula, all four variables can be directly measured. To facilitate calculation, a new dimensionless variable can be defined:

[0093]

[0094] in, R represents the actual mass flow rate of the experimental specimen. g T0 represents the gas constant. * The inlet temperature of the test specimen is represented by A, and the outlet area of ​​the test specimen is represented by p0. * π represents the total inlet pressure of the experimental specimen, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

[0095] Furthermore, for multiple measurement conditions, the correction factor is the arithmetic mean of the ratios of the measurements from the reference flowmeter and the flowmeter to be corrected, expressed as follows:

[0096]

[0097] Where n represents the number of measurement control systems, (F T,ME,i ) R Represents the first measured value of the i-th measurement condition, (F T,ME,i ) C I represents the second measured value for the i-th measurement condition. i,R I represents the dimensionless variable corresponding to the reference flow meter in the i-th operating condition. i,C This represents the dimensionless variable corresponding to the flowmeter to be corrected in the i-th operating condition.

[0098] S4: Determine the number of flow meters in the parallel flow meter group, and determine the sub-flow correction coefficient for each flow meter based on the number of flow meters and the flow correction coefficient.

[0099] Figure 3 is a flowchart of a flow coefficient correction method for switching measurements of parallel flowmeter groups provided in Embodiment 1 of the present invention. Step S4 mainly includes the following steps S41 to S42:

[0100] S41: Determine the sum of squares of deviations of the parallel flow meter group and the relationship of correction coefficients between two adjacent flow meters based on the number of flow meters.

[0101] Furthermore, assume there are P flow meters in the parallel flow meter group, and the measured flow rates of the flow meters are denoted as 1, 2, ..., P in ascending order. The correction factor for flow meter j is denoted as ζ. j Let the variable to be corrected be denoted as x (the variable to be corrected in the correction method is I), then the corrected value can be denoted as ζ. j x. The sum of squared deviations of the corrected values ​​of the flow meter group can be expressed as:

[0102]

[0103] Where M represents the sum of squared deviations, P represents the number of flow meters in the flow meter group, and n j The number of measurement conditions is represented by ζ, x represents the variable to be corrected, and ζ represents the variable to be corrected. j Let represent the correction factor for the j-th flow meter. Then, the relationship between the correction factors of two adjacent flow meters is:

[0104]

[0105] Where, ζ j+1 ζj represents the correction coefficient for the (j+1)th flow meter, nj represents the number of measurement conditions, x represents the variable to be corrected, and ζj represents the correction coefficient for the j-th flow meter.

[0106] S42: Determine the correction coefficient for each sub-flow rate based on the sum of squared deviations and the relationship between the correction coefficients.

[0107] Specifically, j = 1 to P-1. M in equation (11) can be expressed as a quadratic function of ζ1, i.e., M = M(ζ1). The condition for minimizing the sum of squares of the deviations is:

[0108]

[0109] Where M represents the sum of squared deviations and ζ1 represents the correction coefficient of the first flow meter. The flow correction coefficient of each flow meter can be obtained by combining formulas (10), (11) and (12).

[0110] S5: The flow coefficient of each flow meter is corrected by the sub-flow correction coefficient to achieve the flow coefficient correction of the parallel flow meter group.

[0111] Specifically, for parallel flow meter groups with more than two flow meters, the flow correction coefficient of each flow meter in the parallel flow meter group is obtained by linear regression using the least squares method, so as to ensure both the measurement accuracy of each flow meter and the smooth transition of the measured flow of the parallel flow meter group.

[0112] The technical solution of this invention uses a parallel flowmeter group as the flowmeter to be corrected in the experiment and sets a reference flowmeter for the experiment; it determines the first measured value of the adiabatic index correlation function corresponding to the reference flowmeter and the second measured value of the adiabatic index correlation function corresponding to the flowmeter to be corrected, and defines the adiabatic index correlation function as a reference for correction, ensuring correction accuracy. The sub-flow correction coefficient corresponding to each flowmeter is determined according to the number of flowmeters and the flow correction coefficient; the flow coefficient of each flowmeter is corrected using the sub-flow correction coefficient, which enables a smooth transition in the flow measurement of the parallel flowmeter group, and has low requirements for experimental measurement conditions, reducing time and economic costs.

[0113] Example 2

[0114] This embodiment is a method for correcting the flow coefficient when switching between parallel flow meter groups. Based on the above embodiment one, this embodiment adds an application scenario to specifically explain the flow coefficient correction process.

[0115] Figure 4 is a schematic diagram of the experimental platform structure provided in this embodiment. Flow correction of the parallel flowmeter group requires flow measurement experiments on the experimental platform. The experimental platform selected in this embodiment is a planar toothed experimental platform. In Figure 4, 1 represents the experimental platform inlet, 2 represents the air inlet section, 3 represents the contraction tube section, 4 represents the toothed experimental section, 5 represents the outlet section, and 6 represents the experimental platform outlet. The upper and lower cover plates of the planar toothed experimental piece are machined separately, and the tooth tip clearance CL can be adjusted by adjusting the height of the shims. Figure 5 is a schematic diagram of the helical tooth structure of an experimental piece provided in this embodiment. In Figure 5, the tooth inclination angle α... L Tooth back tilt angle β L The angles are 15° and 30° respectively, with 5 teeth, a tooth tip clearance CL of 0.49 mm, a tooth tip width z of 0.3 mm, a tooth pitch q of 4 mm, and a tooth height h. L It is 4mm.

[0116] Furthermore, based on the flow correction principle, total pressure and total temperature measurement points need to be arranged at the inlet of the test piece, and static pressure measurement points need to be arranged at the outlet of the test piece. In this embodiment, pressure and temperature measurement points are arranged in the air inlet chamber of the planar grate test platform to measure the inlet pressure and inlet temperature; a pressure measurement point is arranged at the grate outlet to measure the outlet static pressure.

[0117] Specifically, in this embodiment, the parallel flow meters that need to be modified are 1-2#, 2#, and 3#, with the measured flow rates of the three flow meters increasing sequentially. Furthermore, in this embodiment, the parallel flow meter group is installed upstream of the experimental platform to measure the mass flow rate of the toothed experimental platform.

[0118] Furthermore, the measurement conditions need to be determined. The experimental conditions for the test specimen can be determined based on the measurement range of the parallel flowmeter group. In this embodiment, the experimental conditions corresponding to the measurement range of flowmeters 1-2 are: an outlet pressure of 100 kPa and a pressure ratio of 1.05–2.1; the experimental conditions corresponding to the measurement range of flowmeter 2 are: an outlet pressure of 100 kPa and a pressure ratio of 1.5–3.0; and the experimental conditions corresponding to the measurement range of flowmeter 3 are: an outlet pressure of 200 kPa and a pressure ratio of 2.0–3.8.

[0119] Specifically, measurements are performed according to the measurement conditions to obtain the flow coefficient characteristic curve. Figure 6 is a schematic diagram of the characteristic curve of the flow coefficient before correction with pressure ratio provided in this embodiment. In Figure 6, the vertical axis represents the flow coefficient, and the horizontal axis represents the pressure ratio. The black squares represent the flow coefficient before correction with pressure ratio of flowmeters 1-2# at an outlet pressure of 100 kPa, the black circles represent the flow coefficient before correction with pressure ratio of flowmeter 2# at an outlet pressure of 100 kPa, the black triangles represent the flow coefficient before correction with pressure ratio of flowmeter 2# at an outlet pressure of 200 kPa, and the white triangles represent the flow coefficient before correction with pressure ratio of flowmeter 3# at an outlet pressure of 200 kPa. It can be seen that under the same operating conditions, the flow coefficient measured by flowmeters 1-2# is greater than that measured by flowmeter 2#, with a maximum deviation of 1.2%; while the flow coefficient measured by flowmeter 2# is greater than that measured by flowmeter 3#, with a maximum deviation of 1.6%.

[0120] Furthermore, the sub-flow correction coefficients of each parallel flowmeter can be obtained according to equation (11) in Embodiment 1. Figure 7 is a schematic diagram of the characteristic curve of the corrected flow coefficient with pressure ratio provided in this embodiment. In Figure 7, the vertical axis represents the flow coefficient, the horizontal axis represents the pressure ratio, the black square represents the corrected flow coefficient of flowmeter 1-2# with pressure ratio at an outlet pressure of 100 kPa, the black circle represents the corrected flow coefficient of flowmeter 2# with pressure ratio at an outlet pressure of 100 kPa, the black triangle represents the corrected flow coefficient of flowmeter 2# with pressure ratio at an outlet pressure of 200 kPa, and the white triangle represents the corrected flow coefficient of flowmeter 3# with pressure ratio at an outlet pressure of 200 kPa. The correction coefficients of flowmeters 1-2#, 2# and 3# calculated by the least squares method are 0.9916, 0.9977 and 1.0117, respectively. Comparing Figures 6 and 7, it can be seen that the measurement deviation in the transition region between flow meters 1-2# and 2# and 3# is significantly reduced after correction, and the transition region of the flow coefficient is smoother. The maximum measurement deviation of flow meters 1-2# and 2# is reduced to 0.6% after correction, while the maximum measurement deviation of flow meters 2# and 3# is reduced to 0.2%. Compared with before correction, the transition of flow measurement between flow meters is smoother.

[0121] The technical solution of this invention uses a parallel flowmeter group as the flowmeter to be corrected in the experiment and sets a reference flowmeter for the experiment; it determines the first measured value of the adiabatic index correlation function corresponding to the reference flowmeter and the second measured value of the adiabatic index correlation function corresponding to the flowmeter to be corrected, and defines the adiabatic index correlation function as a reference for correction, ensuring correction accuracy. The sub-flow correction coefficient corresponding to each flowmeter is determined according to the number of flowmeters and the flow correction coefficient; the flow coefficient of each flowmeter is corrected using the sub-flow correction coefficient, which enables a smooth transition in the flow measurement of the parallel flowmeter group, and has low requirements for experimental measurement conditions, reducing time and economic costs.

[0122] Example 3

[0123] Figure 8 is a schematic diagram of a flow coefficient correction device for switching measurements of parallel flowmeter groups provided in Embodiment 3 of the present invention. This device can be implemented in software and / or hardware, and is generally integrated into the electronic device performing the method. As shown in Figure 8, the device includes: a flowmeter setting module 310, used to set the parallel flowmeter group as the flowmeter to be corrected in the experimental setup and a reference flowmeter in the experimental setup; a measurement value determination module 320, used to determine a first measurement value of the adiabatic index correlation function corresponding to the reference flowmeter and a second measurement value of the adiabatic index correlation function corresponding to the flowmeter to be corrected; a flow correction coefficient determination module 330, used to use the ratio of the first measurement value and the second measurement value as the flow correction coefficient; a sub-flow correction coefficient determination module 340, used to determine the sub-flow correction coefficient corresponding to each flowmeter based on the number of flowmeters in the parallel flowmeter group and the flow correction coefficient; and a flow coefficient correction module 350, used to correct the flow coefficient of each flowmeter through the sub-flow correction coefficient to achieve flow coefficient correction of the parallel flowmeter group.

[0124] Optionally, the measurement value determination module 320 specifically includes: an actual mass flow rate measurement unit, used to measure the first actual mass flow rate of the experimental specimen using a reference flow meter, and to measure the second actual mass flow rate of the experimental specimen using a flow meter to be corrected; an adiabatic index correlation function definition unit, used to define an adiabatic index correlation function; and a measurement value determination unit, used to determine the first measurement value and the second measurement value based on the first actual mass flow rate, the second actual mass flow rate, and the adiabatic index correlation function.

[0125] Optionally, the actual mass flow rate in the actual mass flow rate measurement unit is expressed as:

[0126]

[0127] in, C represents the actual mass flow rate of the experimental specimen. D Indicates the flow coefficient of the experimental specimen. p0 represents the ideal mass flow rate of the experimental specimen. * R represents the total inlet pressure of the test specimen, A represents the outlet area of ​​the test specimen, and R represents the total inlet pressure of the test specimen. g T0 represents the gas constant. * The total inlet temperature of the experimental specimen is represented by π, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

[0128] Optionally, the adiabatic index correlation function defined in the adiabatic index correlation function definition unit is:

[0129]

[0130] Among them, F T represents the adiabatic index correlation function, and k represents the isentropic index.

[0131] Optionally, the principle for calculating the measured value in the measured value determination unit is as follows:

[0132]

[0133] Among them, F T,ME Indicates the measured value. R represents the actual mass flow rate of the experimental specimen. g T0 represents the gas constant. * The total inlet temperature of the test specimen is represented by C. D p0 represents the flow coefficient of the experimental specimen, A represents the outlet area of ​​the experimental specimen, and p0 represents the flow coefficient of the experimental specimen. * π represents the total inlet pressure of the experimental specimen, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

[0134] Optionally, the flow correction factor in the flow correction factor determination module 330 is expressed as follows:

[0135]

[0136] Among them, F T,ME The values ​​represent the measured values. The subscript R indicates the first measured value from the reference flowmeter, and the subscript C indicates the second measured value from the flowmeter to be corrected. R represents the actual mass flow rate of the experimental specimen. g T0 represents the gas constant. * The total inlet temperature of the test specimen is represented by C. D p0 represents the flow coefficient of the experimental specimen, A represents the outlet area of ​​the experimental specimen, and p0 represents the flow coefficient of the experimental specimen. * π represents the total inlet pressure of the experimental specimen, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

[0137] Optionally, the sub-flow correction coefficient determination module 340 is specifically used to: determine the sum of squares of the deviations of the parallel flow meter group and the relationship of the correction coefficients of two adjacent flow meters based on the number of flow meters; and determine the correction coefficients of each sub-flow based on the sum of squares of the deviations and the relationship of the correction coefficients.

[0138] The technical solution of this invention uses a parallel flowmeter group as the flowmeter to be corrected in the experiment and sets a reference flowmeter for the experiment; it determines the first measured value of the adiabatic index correlation function corresponding to the reference flowmeter and the second measured value of the adiabatic index correlation function corresponding to the flowmeter to be corrected, and defines the adiabatic index correlation function as a reference for correction, ensuring correction accuracy. The sub-flow correction coefficient corresponding to each flowmeter is determined according to the number of flowmeters and the flow correction coefficient; the flow coefficient of each flowmeter is corrected using the sub-flow correction coefficient, which enables a smooth transition in the flow measurement of the parallel flowmeter group, and has low requirements for experimental measurement conditions, reducing time and economic costs.

[0139] The flow coefficient correction device for parallel flow meter group switching measurement provided in this embodiment of the invention can execute the flow coefficient correction method for parallel flow meter group switching measurement provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method.

[0140] Example 4

[0141] Figure 9 is a schematic diagram of the structure of an electronic device 400 provided in Embodiment 4 of the present invention. The electronic device in this embodiment can be a device corresponding to the backend service platform of an application, or a mobile terminal device with an application client installed. Specifically, the electronic device can include, but is not limited to, mobile terminals such as mobile phones, laptops, digital radio receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), and in-vehicle terminals (e.g., in-vehicle navigation terminals), as well as fixed terminals such as digital TVs and desktop computers. The electronic device shown in Figure 9 is merely an example and should not impose any limitations on the functionality and scope of use of the embodiments of this disclosure.

[0142] As shown in Figure 8, the electronic device 400 may include a processing unit (e.g., a central processing unit, a graphics processing unit, etc.) 401, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 402 or a program loaded from a storage device 408 into a random access memory (RAM) 403. The RAM 403 also stores various programs and data required for the operation of the electronic device 400. The processing unit 401, ROM 402, and RAM 403 are interconnected via a bus 404. An input / output (I / O) interface 405 is also connected to the bus 404.

[0143] Typically, the following devices can be connected to I / O interface 405: input devices 406 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 407 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; storage devices 408 including, for example, magnetic tapes, hard disks, etc.; and communication devices 409. Communication device 409 allows electronic device 400 to communicate wirelessly or wiredly with other devices to exchange data. Although Figure 3 shows electronic device 400 with various devices, it should be understood that it is not required to implement or possess all of the devices shown. More or fewer devices may be implemented or possessed alternatively.

[0144] In particular, according to embodiments of this disclosure, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of this disclosure include a computer program product comprising a computer program carried on a non-transitory computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication device 409, or installed from storage device 408, or installed from ROM 402. When the computer program is executed by processing device 401, it performs the functions defined in the methods of embodiments of this disclosure.

[0145] It should be noted that the computer-readable medium described in this disclosure can be a computer-readable signal medium or a computer-readable storage medium, or any combination thereof. A computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this disclosure, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this disclosure, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium can be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wires, optical fibers, RF (radio frequency), etc., or any suitable combination thereof.

[0146] In some implementations, clients and servers can communicate using any currently known or future-developed network protocol such as HTTP (Hypertext Transfer Protocol) and can interconnect with digital data communication (e.g., communication networks) of any form or medium. Examples of communication networks include local area networks (“LANs”), wide area networks (“WANs”), the Internet (e.g., the Internet of Things), and peer-to-peer networks (e.g., ad hoc peer-to-peer networks), as well as any currently known or future-developed networks.

[0147] The aforementioned computer-readable medium may be included in the aforementioned electronic device; or it may exist independently and not assembled into the electronic device.

[0148] The aforementioned computer-readable medium carries one or more programs, which, when executed by the electronic device, cause the internal processes of the electronic device to perform the following: using a parallel flow meter group as the flow meter to be corrected in the experimental setup and setting a reference flow meter for the experimental setup; determining a first measured value of the adiabatic index correlation function corresponding to the reference flow meter and a second measured value of the adiabatic index correlation function corresponding to the flow meter to be corrected; using the ratio of the first measured value to the second measured value as a flow correction coefficient; determining the number of flow meters in the parallel flow meter group, and determining a sub-flow correction coefficient corresponding to each flow meter based on the number of flow meters and the flow correction coefficient; and correcting the flow coefficient of each flow meter using the sub-flow correction coefficient to achieve flow coefficient correction for the parallel flow meter group.

[0149] Computer program code for performing the operations of this disclosure can be written in one or more programming languages ​​or a combination thereof, including but not limited to object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0150] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0151] The units described in the embodiments of this disclosure can be implemented in software or hardware. The names of the units are not, in some cases, intended to limit the specific unit.

[0152] The functions described above in this document can be performed, at least in part, by one or more hardware logic components. For example, exemplary types of hardware logic components that can be used, without limitation, include: Field Programmable Gate Arrays (FPGAs), Application-Specific Integrated Circuits (ASICs), Application Standard Products (ASSPs), System-on-Chip (SoCs), Complex Programmable Logic Devices (CPLDs), and so on.

[0153] In the context of this disclosure, a machine-readable medium can be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can be, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of machine-readable storage media include electrical connections based on one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the foregoing.

[0154] The above description is merely a preferred embodiment of this disclosure and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of this disclosure is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features disclosed in this disclosure that have similar functions.

[0155] Furthermore, while the operations are described in a specific order, this should not be construed as requiring these operations to be performed in the specific order shown or in a sequential order. In certain environments, multitasking and parallel processing may be advantageous. Similarly, while several specific implementation details are included in the above discussion, these should not be construed as limiting the scope of this disclosure. Certain features described in the context of individual embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented individually or in any suitable sub-combination in multiple embodiments.

[0156] Although the subject matter has been described using language specific to structural features and / or methodological logic, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are merely illustrative examples of implementing the claims.

Claims

1. A method for correcting the flow coefficient of a parallel flow meter group, characterized in that, Includes the following steps: S1: Use the parallel flow meter group as the flow meter to be corrected in the test piece and set the reference flow meter of the test piece; S2: Determine the first measured value of the adiabatic index correlation function corresponding to the reference flow meter and the second measured value of the adiabatic index correlation function corresponding to the flow meter to be corrected; S3: Use the ratio of the first measured value and the second measured value as the flow correction coefficient; S4: Determine the number of flow meters in the parallel flow meter group, and determine the sub-flow correction coefficient corresponding to each flow meter based on the number of flow meters and the flow correction coefficient; S5: The flow coefficient of each flow meter is corrected using the sub-flow correction coefficient to achieve the flow coefficient correction of the parallel flow meter group; the flow correction coefficient in step S3 is expressed as: Among them, F T,ME The values ​​represent the measured values. The subscript R indicates the first measured value from the reference flowmeter, and the subscript C indicates the second measured value from the flowmeter to be corrected. R represents the actual mass flow rate of the experimental specimen. g T0 represents the gas constant. * The total inlet temperature of the test specimen is represented by C. D p0 represents the flow coefficient of the experimental specimen, A represents the outlet area of ​​the experimental specimen, and p0 represents the flow coefficient of the experimental specimen. * The total inlet pressure of the test specimen is represented by k, the isentropic index is represented by π, and the pressure ratio of the test specimen is represented by π. Step S4 specifically includes: S41: determining the sum of squares of the deviations of the parallel flow meter group and the relationship of the correction coefficients between two adjacent flow meters based on the number of flow meters; S42: determining the correction coefficients of each sub-flow rate based on the sum of squares of the deviations and the relationship of the correction coefficients.

2. The method for correcting the flow coefficient of a parallel flow meter group according to claim 1, characterized in that, Step S2 specifically includes: S21: measuring the first actual mass flow rate of the experimental specimen using the reference flow meter, and measuring the second actual mass flow rate of the experimental specimen using the flow meter to be corrected; S22: defining the adiabatic index correlation function; S23: determining the first measured value and the second measured value based on the first actual mass flow rate, the second actual mass flow rate, and the adiabatic index correlation function.

3. The method for correcting the flow coefficient of a parallel flow meter group according to claim 2, characterized in that, The actual mass flow rate in step S21 is expressed as follows: ;in, C represents the actual mass flow rate of the experimental specimen. D This represents the flow coefficient of the experimental specimen. p0 represents the ideal mass flow rate of the experimental specimen. * R represents the total inlet pressure of the test specimen, A represents the outlet area of ​​the test specimen, and R represents the total inlet pressure of the test specimen. g T0 represents the gas constant. * The total inlet temperature of the experimental specimen is represented by π, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

4. The method for correcting the flow coefficient of a parallel flow meter group according to claim 2, characterized in that, The adiabatic index correlation function defined in step S22 is: Among them, F T represents the adiabatic index correlation function, and k represents the isentropic index.

5. The method for correcting the flow coefficient of a parallel flow meter group according to claim 2, characterized in that, The principle for calculating the measured value in step S23 is as follows: Among them, F T,ME Indicates the measured value. R represents the actual mass flow rate of the experimental specimen. g T0 represents the gas constant. * The total inlet temperature of the test specimen is represented by C. D p0 represents the flow coefficient of the experimental specimen, A represents the outlet area of ​​the experimental specimen, and p0 represents the flow coefficient of the experimental specimen. * π represents the total inlet pressure of the experimental specimen, k represents the isentropic exponent, and π represents the pressure ratio of the experimental specimen.

6. A flow coefficient correction device for a parallel flow meter group, characterized in that, include: A flow meter setting module is used to use a parallel flow meter group as the flow meter to be corrected in the test piece and to set the reference flow meter of the test piece; The measurement value determination module is used to determine the first measurement value of the adiabatic index correlation function corresponding to the reference flow meter and the second measurement value of the adiabatic index correlation function corresponding to the flow meter to be corrected. The flow correction coefficient determination module is used to use the ratio of the first measured value and the second measured value as the flow correction coefficient; the sub-flow correction coefficient determination module is used to determine the sub-flow correction coefficient corresponding to each flow meter based on the number of flow meters in the parallel flow meter group and the flow correction coefficient. A flow coefficient correction module is used to correct the flow coefficient of each flow meter using the sub-flow correction coefficient, thereby achieving flow coefficient correction for the parallel flow meter group; the flow correction coefficient is expressed as: Among them, F T,ME The values ​​represent the measured values. The subscript R indicates the first measured value from the reference flowmeter, and the subscript C indicates the second measured value from the flowmeter to be corrected. R represents the actual mass flow rate of the experimental specimen. g T0 represents the gas constant. * The total inlet temperature of the test specimen is represented by C. D p0 represents the flow coefficient of the experimental specimen, A represents the outlet area of ​​the experimental specimen, and p0 represents the flow coefficient of the experimental specimen. * The total inlet pressure of the test specimen is represented by k, the isentropic index is represented by π, and the pressure ratio of the test specimen is represented by π. "Determining the sub-flow correction coefficient corresponding to each of the flow meters according to the number of flow meters and the flow correction coefficient" specifically includes: determining the sum of squares of the deviations of the parallel flow meter group and the relationship of the correction coefficients of two adjacent flow meters according to the number of flow meters; and determining the sub-flow correction coefficients according to the sum of squares of the deviations and the relationship of the correction coefficients.

7. An electronic device, characterized in that, The electronic device includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, the computer program being executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1-5.

8. A computer storage medium, characterized in that, The computer storage medium stores computer instructions that are used to cause a processor to execute the method of any one of claims 1-5.

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