CN113627100B - Method, device and electronic device for determining flow coefficient - Google Patents

Abstract

The invention provides a flow coefficient determining method, a flow coefficient determining device and electronic equipment, which are used for carrying out simulation processing on a preset valve flow field simulation model based on a simulation instruction and preset simulation parameters after receiving the simulation instruction sent by a user, and calculating an error result based on the obtained simulation result and a preset experiment result; if the error result accords with the preset result, continuing to execute the step of receiving the simulation instruction sent by the user until the preset condition is reached, obtaining a final valve flow field simulation model, and determining the flow coefficient based on the final valve flow field simulation model and the preset simulation parameters. The method can determine the flow coefficient based on the final valve flow field simulation model and the preset simulation parameters, and can obtain the final valve flow field simulation model meeting the precision requirement only by a limited amount of experimental data, so that the requirement on the amount of experimental data can be reduced, and the acquisition efficiency of the flow coefficient is improved while the flow coefficient meeting the precision requirement is obtained.

Description

Method, device and electronic device for determining flow coefficient

Technical Field

The present invention relates to the technical field of regulating valves, and in particular to a method, device and electronic equipment for determining a flow coefficient.

Background technique

The sleeve valve is a type of regulating valve. The main structure of the sleeve valve is a pair of sleeves that overlap inside and outside. The wall of the inner sleeve is symmetrically distributed with throttle holes for controlling the fluid flow. By changing the shape and size of the throttle holes, the flow characteristics of the sleeve valve can be changed more conveniently. The sleeve valve is used as a regulating valve for the pipe network control system. When designing the pipe network control system, the flow characteristics of the sleeve valve need to be determined first. Specifically, the flow coefficient of the sleeve valve usually needs to be determined. In the related technology, the scatter plot of the actual test data is usually analyzed by a neural network algorithm, or the related method of iterative fitting regression is performed on the collected scatter data. Although these methods can obtain a high-precision flow coefficient, they have high requirements on the number of test data, and the efficiency of obtaining the flow coefficient is low. If the number of test data is insufficient or small, it is difficult to obtain a flow coefficient that meets the accuracy requirements by the above method.

Summary of the invention

The object of the present invention is to provide a method, device and electronic equipment for determining a flow coefficient, so as to improve processing efficiency and the accuracy of the flow coefficient.

The present invention provides a method for determining a flow coefficient, which includes: receiving a simulation instruction issued by a user; simulating a preset valve flow field simulation model based on the simulation instruction and preset simulation parameters to obtain a simulation result; calculating an error result based on the simulation result and a preset experimental result; if the error result meets the preset result, continuing to execute the step of receiving the simulation instruction issued by the user until a preset condition is met to obtain a final valve flow field simulation model; and determining the flow coefficient based on the final valve flow field simulation model and the preset simulation parameters.

Furthermore, the preset valve flow field simulation model is determined in the following manner: receiving a model building instruction issued by a user; building a valve three-dimensional model according to the model building instruction; receiving a model import instruction and preset import parameters issued by the user; based on the model import instruction and the preset import parameters, inputting the valve three-dimensional model into the preset simulation software to obtain a valve flow field simulation model corresponding to the valve three-dimensional model.

Furthermore, the preset conditions include: the error result does not meet the preset result, or the number of error results reaches a preset number.

Furthermore, the simulation parameters include multiple groups, each group of simulation parameters includes a valve opening data and a valve pressure ratio, wherein the valve pressure ratio includes: the ratio of the valve's post-valve pressure to the valve's pre-valve pressure; based on the final valve flow field simulation model and preset simulation parameters, the step of determining the flow coefficient includes: for each group of simulation parameters, based on the final valve flow field simulation model and the group of simulation parameters, determining the simulation flow corresponding to the group of simulation parameters; based on the simulation flow corresponding to the group of simulation parameters, determining the flow coefficient corresponding to the group of simulation parameters; based on the flow coefficient corresponding to each group of simulation parameters, determining a flow coefficient set.

Furthermore, the method also includes: performing interpolation processing on the flow coefficient set to obtain a processed flow coefficient set; inputting the processed flow coefficient set and preset input parameters into a preset simulation verification model to obtain an output result.

The present invention provides a flow coefficient determination device, which includes: a receiving module, which is used to receive a simulation instruction issued by a user; a simulation module, which is used to simulate a preset valve flow field simulation model based on the simulation instruction and preset simulation parameters to obtain a simulation result; a calculation module, which is used to calculate an error result based on the simulation result and a preset experimental result; a first determination module, which is used to continue to execute the step of receiving the simulation instruction issued by the user if the error result meets the preset result, until the preset condition is met to obtain a final valve flow field simulation model; and a second determination module, which is used to determine the flow coefficient based on the final valve flow field simulation model and preset simulation parameters.

Furthermore, the device also includes: a valve flow field simulation model determination module; the valve flow field simulation model determination module is used to: receive a model building instruction issued by a user; build a valve three-dimensional model according to the model building instruction; receive a model import instruction and preset import parameters issued by a user; based on the model import instruction and the preset import parameters, input the valve three-dimensional model into the preset simulation software to obtain a valve flow field simulation model corresponding to the valve three-dimensional model.

Furthermore, the preset conditions include: the error result does not meet the preset result, or the number of error results reaches a preset number.

Furthermore, the simulation parameters include multiple groups, each group of simulation parameters includes a valve opening data and a valve pressure ratio, wherein the valve pressure ratio includes: the ratio of the valve's post-valve pressure to the valve's pre-valve pressure; the second determination module is also used to: for each group of simulation parameters, determine the simulation flow corresponding to the group of simulation parameters based on the final valve flow field simulation model and the group of simulation parameters; determine the flow coefficient corresponding to the group of simulation parameters based on the simulation flow corresponding to the group of simulation parameters; determine the flow coefficient set based on the flow coefficient corresponding to each group of simulation parameters.

An electronic device provided by the present invention includes a processor and a memory, wherein the memory stores machine executable instructions that can be executed by the processor, and the processor executes the machine executable instructions to implement any of the above flow coefficient determination methods.

The flow coefficient determination method, device and electronic device provided by the present invention can simulate a preset valve flow field simulation model based on the simulation instruction and preset simulation parameters after receiving a simulation instruction issued by a user, and calculate an error result based on the obtained simulation result and the preset experimental result; if the error result meets the preset result, continue to execute the step of receiving the simulation instruction issued by the user until the preset condition is met, and obtain the final valve flow field simulation model, and determine the flow coefficient based on the final valve flow field simulation model and the preset simulation parameters. This method can determine the flow coefficient based on the final valve flow field simulation model and the preset simulation parameters, and only a limited number of experimental data are needed to obtain the final valve flow field simulation model that meets the accuracy requirements, thereby reducing the requirements for the number of experimental data, and while obtaining a flow coefficient that meets the accuracy requirements, the efficiency of obtaining the flow coefficient is improved.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a flow chart of a method for determining a flow coefficient provided by an embodiment of the present invention;

FIG2 is a flow chart of another method for determining a flow coefficient provided by an embodiment of the present invention;

FIG3 is a schematic structural diagram of a sleeve valve provided in an embodiment of the present invention;

FIG4 is a flow chart of a method for acquiring flow characteristics provided by an embodiment of the present invention;

FIG5 is a schematic diagram of a three-dimensional flow field simulation model of a sleeve valve provided in an embodiment of the present invention;

FIG6 is a schematic diagram of a flow coefficient surface provided by an embodiment of the present invention;

FIG7 is a schematic diagram of a first flow test output comparison according to an embodiment of the present invention;

FIG8 is a relative error analysis diagram of a first flow test provided by an embodiment of the present invention;

FIG9 is a schematic diagram of a second flow test output comparison according to an embodiment of the present invention;

FIG10 is a relative error analysis diagram of a second flow test provided by an embodiment of the present invention;

FIG11 is a schematic structural diagram of a flow coefficient determination device provided by an embodiment of the present invention;

FIG. 12 is a schematic diagram of the structure of an electronic device provided by an embodiment of the present invention.

Detailed ways

The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

As a regulating valve of the pipe network control system, the sleeve valve needs to obtain the flow characteristics of the sleeve valve first when designing the pipe network control system. Specifically, it is usually necessary to determine the flow coefficient of the sleeve valve. In the related art, for large-caliber sleeve valves, the flow characteristic interpolation can usually be directly obtained through actual test methods. This method is not only costly and has a long R&D cycle, but also the accuracy cannot be effectively guaranteed. It is generally not used as a mainstream method. In another way, the main method used to obtain the flow characteristics of the regulating valve is to analyze the flow characteristics using computational fluid dynamics (CFD) technology for the specific regulating valve model. Since the numerical simulation software of CFD on the market has been developed to a relatively mature level, this method can achieve high-precision simulation results with high efficiency; but the disadvantages of this method are also obvious. In this method, the accuracy quality of the flow coefficient table is very dependent on the professional quality and simulation experience of the simulation personnel, which makes the dispersion of the flow coefficient accuracy of the same model valve under different working conditions large, which brings model errors to the subsequent control system modeling and simulation. In another method, a neural network algorithm can be used to analyze the scatter plot of actual test data, or a related method of iterative fitting regression can be used through the collected scattered data. Although this method can obtain a flow coefficient table with higher accuracy, it has high requirements on the amount of test data. If the amount of test data is insufficient or small, it is difficult to obtain a flow coefficient that meets the accuracy requirements using the above method.

Based on this, an embodiment of the present invention provides a flow coefficient determination method, device and electronic device. This technology can be applied to applications that need to obtain the flow characteristics of a control valve, and specifically can be applied to applications that need to obtain the flow coefficient of a control valve.

To facilitate understanding of this embodiment, a method for determining a flow coefficient disclosed in an embodiment of the present invention is first introduced in detail; as shown in FIG1 , the method includes the following steps:

Step S102, receiving a simulation instruction issued by a user.

The above-mentioned simulation instruction can be understood as an instruction issued by the user to simulate the preset valve flow field simulation model; in actual implementation, the simulation instruction issued by the user can be received through the simulation software, wherein the analysis software can be a flow field simulation software, such as ANSYS Fluent or STAR-CCM (Computational Continuum Mechanics).

Step S104, based on the simulation instruction and the preset simulation parameters, the preset valve flow field simulation model is simulated to obtain a simulation result.

The above-mentioned valve flow field simulation model can be a three-dimensional flow field simulation model of a sleeve valve, etc. The valve flow field simulation model is usually drawn with a grid and is usually configured with relevant configuration parameters, such as the pressure before the valve, the temperature before the valve, the valve opening, the pressure after the valve, etc.; the above-mentioned simulation parameters usually include preset parameters such as boundary conditions, number of iterations or convergence indicators pre-set for the valve flow field simulation model; in actual implementation, after receiving the simulation instruction issued by the user, the valve flow field simulation model can be simulated according to the simulation instruction and the pre-set simulation parameters to obtain a simulation result. For the valve flow field simulation model, the simulation result is usually the output flow rate of the valve, that is, the mass flow rate of the valve, wherein the mass flow rate can be understood as the mass of the fluid passing through the effective cross-section of a closed pipe or an open groove per unit time, and the unit is usually kg/s or kg/h, etc.

Step S106, calculating the error result based on the simulation result and the preset experimental result.

The above-mentioned preset experimental results are usually the actual experimental flow results under the same conditions as the simulation process, for example, the actual experimental results with the same valve front pressure, valve front temperature, valve opening and valve rear pressure as the simulation process; the error result is usually the relative error between the simulation result and the preset experimental result. For example, the calculation formula of the relative error can be: relative error = |simulation result-preset experimental result|/preset experimental result*100%.

Step S108, if the error result meets the preset result, continue to execute the step of receiving the simulation instruction issued by the user until the preset condition is met to obtain the final valve flow field simulation model.

The above-mentioned preset result is usually a preset relative error threshold, for example, the relative error threshold may be 7% or 8%, etc., and the preset result may be set specifically according to actual needs; in actual implementation, the above-mentioned error result may be compared with the preset result to confirm whether the above-mentioned error result meets the accuracy requirement. If the error result meets the preset result, the above-mentioned step of receiving the simulation instruction issued by the user is usually repeated until the preset condition is reached. The preset condition may be used to indicate the condition for stopping the repetitive process, for example, the preset condition may be that the number of error results obtained reaches a specified number, or it may be understood that the number of repeated executions reaches a specified number, etc. For example, the execution is repeated 10 times to obtain 10 error results, etc.; after the above-mentioned preset condition is reached, the above-mentioned final valve flow field simulation model is obtained, and the final valve flow field simulation model may be understood as a model that can meet the accuracy requirements under different boundary conditions.

If the above error result does not conform to the preset result, a corresponding prompt information can be generated, which can be used to prompt the user that the preset valve flow field simulation model may need to be modified. Specifically, the user can analyze the cause according to the error result to modify the simulation model.

Step S110, determining the flow coefficient based on the final valve flow field simulation model and preset simulation parameters.

The above-mentioned preset simulation parameters can be one or more different combinations of valve opening and valve pressure ratio, for example, the valve opening is 10°, 20°, ..., 90° and the pressure ratio is 0.1, 0.2, ..., 0.9; wherein, the valve pressure ratio can be the ratio between the pressure after the valve and the pressure before the valve; after obtaining the above-mentioned final valve flow field simulation model, the above-mentioned flow coefficient can be obtained based on the final valve flow field simulation model and the preset simulation parameters. When the simulation parameters include multiple different combinations, the above-mentioned flow coefficient usually also includes multiple flow coefficients, and the multiple flow coefficients can be expressed in tabular form, that is, a flow coefficient table is obtained.

The above-mentioned flow coefficient determination method, after receiving the simulation instruction issued by the user, can simulate the preset valve flow field simulation model based on the simulation instruction and the preset simulation parameters, and calculate the error result based on the obtained simulation result and the preset experimental result; if the error result meets the preset result, continue to execute the step of receiving the simulation instruction issued by the user until the preset condition is met, and the final valve flow field simulation model is obtained, and the flow coefficient is determined based on the final valve flow field simulation model and the preset simulation parameters. This method can determine the flow coefficient based on the final valve flow field simulation model and the preset simulation parameters, and only a limited number of experimental data are needed to obtain the final valve flow field simulation model that meets the accuracy requirements, thereby reducing the requirements for the number of experimental data, and while obtaining the flow coefficient that meets the accuracy requirements, the efficiency of obtaining the flow coefficient is improved.

The embodiment of the present invention also provides another method for determining the flow coefficient, which is implemented on the basis of the method of the above embodiment; the method focuses on describing the specific process of determining the flow coefficient based on the final valve flow field simulation model and preset simulation parameters, in which the simulation parameters include multiple groups, each group of simulation parameters includes a valve opening data and a valve pressure ratio, wherein the valve pressure ratio includes: the ratio of the valve back pressure to the valve front pressure; wherein the valve opening data can be expressed as an angle value, for example, the valve opening can be 10°, 20°, 30°, etc., and the valve opening is generally proportional to the mass flow, that is, the larger the valve opening, the higher the mass flow; as shown in FIG. 2 , the method includes the following steps:

Step S202, receiving a simulation instruction issued by a user.

Step S204: based on the simulation instruction and the preset simulation parameters, the preset valve flow field simulation model is simulated to obtain a simulation result.

In actual implementation, the above preset valve flow field simulation model is determined through the following steps 1 to 4:

Step 1: Receive the model building instruction issued by the user.

Step 2: Build a three-dimensional model of the valve according to the model building instructions.

The above-mentioned model building instructions can be understood as instructions issued when the user needs to build a three-dimensional model of a valve; in actual implementation, the above-mentioned model building instructions can be received through three-dimensional modeling software. After receiving the model building instructions, a three-dimensional model of the valve can be built based on the model building instructions. For example, a three-dimensional model of a sleeve valve can be built; it should be noted that, in general, valves are components of a pipeline control system. Therefore, when building a three-dimensional model of a valve, a three-dimensional pipeline network model including the valve is usually built. Specifically, the user can analyze the physical structure of the actual test pipeline and build a three-dimensional pipeline network model through three-dimensional modeling software.

Step three: receiving the model import instruction and preset import parameters issued by the user.

Step 4: Based on the model import instruction and preset import parameters, the valve three-dimensional model is input into the preset simulation software to obtain a valve flow field simulation model corresponding to the valve three-dimensional model.

The above-mentioned model import instruction can be understood as an instruction issued when the user needs to import the above-mentioned constructed valve three-dimensional model into the preset simulation software; the above-mentioned import parameters can be relevant parameters such as local mesh encryption and mesh size setting set by the user; in actual implementation, the valve three-dimensional model can be imported into the preset simulation software based on the received model import instruction and the preset import parameters to perform flow field modeling and draw the mesh to obtain the above-mentioned valve flow field simulation model; the above-mentioned preset simulation software can be finite element analysis pre-processing software or flow field simulation software, etc.; if a three-dimensional pipe network model is constructed, the constructed three-dimensional pipe network model can be imported into the finite element analysis pre-processing software or flow field simulation software for flow field modeling and mesh drawing.

Step S206, calculating the error result based on the simulation result and the preset experimental result.

Step S208: If the error result meets the preset result, continue to execute the step of receiving the simulation instruction issued by the user until the preset condition is met to obtain the final valve flow field simulation model.

The above-mentioned preset conditions include: the error result does not meet the preset result, or the number of error results reaches the preset number. In actual implementation, if the error result meets the accuracy requirement, the step of receiving the simulation instruction issued by the user can be repeatedly executed until the error result no longer meets the preset result, or the number of test points is sufficient to prove the model accuracy range. For example, repeating the test ten times can be considered that the model accuracy meets the requirement.

Step S210, for each set of simulation parameters, based on the final valve flow field simulation model and the set of simulation parameters, determining the simulation flow corresponding to the set of simulation parameters.

After determining that the constructed valve flow field simulation model meets the accuracy requirements under different boundary conditions, flow field simulation is carried out at openings of 10°, 20°, …, 90° and pressure ratios of 0.1, 0.2, …, 0.9, respectively, to obtain the simulated flow rates at different openings and pressure ratios, i.e., the output flow rates. Multiple output flow rates can be represented in the form of an equidistant two-dimensional interpolation table of output flow rates.

Step S212, based on the simulated flow corresponding to the set of simulation parameters, determine the flow coefficient corresponding to the set of simulation parameters.

See the structural schematic diagram of a sleeve valve shown in Figure 3, where Figure 3(a) is a front view of the sleeve valve, Figure 3(b) is an oblique view of the sleeve valve, and Figure 3(c) is an exploded view of the sleeve valve; the sleeve valve is a type of regulating valve, and the sleeve valve adjusts the valve opening through the relative displacement between the sleeve and the valve core to affect the flow of the regulating valve. According to relevant literature, the flow of the sleeve valve can be calculated by the following formula:

Where _Qm is the mass flow rate of the sleeve valve, is the flow coefficient of the sleeve valve, S is the flow cross-sectional area of the regulating valve, _T1 and _P1 are the temperature and pressure of the gas flow before the valve, and R is the known ideal gas constant.

Since T1 and P1 are measured in the experiment, S can be calculated by the valve opening, and the valve opening can also be measured in the experiment. Therefore, after determining the simulated flow corresponding to the simulation parameters, the corresponding flow coefficient is determined according to formula (1).

Step S214, determining a set of flow coefficients based on the flow coefficients corresponding to each set of simulation parameters.

Specifically, after obtaining the flow coefficient corresponding to each set of simulation parameters, a flow coefficient set can be obtained, and the flow coefficient set can be expressed in the form of a two-dimensional interpolation table of flow coefficients.

Step S216, interpolation processing is performed on the flow coefficient set to obtain a processed flow coefficient set.

In actual implementation, if the flow coefficient set is represented in the form of a two-dimensional interpolation table of flow coefficients, the two-dimensional interpolation table can be extrapolated to fill in the boundary parameters; for example, when the valve pressure ratio is 0 and 1 respectively, the corresponding flow coefficients at different valve openings are added.

Step S218, input the processed flow coefficient set and preset input parameters into a preset simulation verification model to obtain an output result.

After obtaining the flow coefficient set after the above interpolation processing, the processed flow coefficient set can be substituted into the software Matlab/Simulink, and the experimental mechanism model can be constructed with other corresponding modules. The input during the actual test is used as the simulation input signal for simulation to obtain the simulated flow output curve, that is, the above output result. The obtained output result can be compared and analyzed with the actual test flow output curve to determine the relative error range and draw a conclusion.

The above-mentioned flow coefficient determination method, for each set of simulation parameters, determines the simulated flow corresponding to the set of simulation parameters based on the final valve flow field simulation model and the set of simulation parameters. Based on the simulated flow corresponding to the set of simulation parameters, determine the flow coefficient corresponding to the set of simulation parameters. Based on the flow coefficient corresponding to each set of simulation parameters, determine the flow coefficient set. Perform interpolation processing on the flow coefficient set to obtain a processed flow coefficient set. Input the processed flow coefficient set and preset input parameters into the preset simulation verification model to obtain an output result. This method can determine the flow coefficient based on the final valve flow field simulation model and multiple sets of simulation parameters. Only a limited number of experimental data are needed to obtain the final valve flow field simulation model that meets the accuracy requirements, thereby reducing the requirements on the number of experimental data, while obtaining a flow coefficient that meets the accuracy requirements, and improving the efficiency of obtaining the flow coefficient.

To further understand the above embodiment, combined with the above formula (1), it can be known that we only need to know The flow rate through the valve can be obtained. According to the research on the valve flow coefficient, /> It mainly depends on the pressure ratio before and after the valve and the valve opening, so the flow coefficient can be described as

In formula (2), P _r =P ₂ /P ₁ represents the pressure ratio before and after the valve, P ₂ represents the pressure after the valve, and V _P represents the opening of the sleeve valve.

Therefore, to obtain the valve flow coefficient at any pressure ratio and any valve opening, it is only necessary to obtain _f1 . Through _f1 , the valve flow coefficient can be solved with the two easily measured values of _Pr and _Vp . The flow rate through the valve can then be calculated.

Since the flow characteristics of the sleeve valve cannot be accurately described by mathematical analytical expressions, that is, _f1 in the above formula (2) cannot be obtained in analytical form only by mathematical modeling, the flow characteristics of the sleeve valve commonly used in engineering are approximated by numerical fitting methods to obtain an approximate solution of the flow characteristics. By substituting its flow characteristics into the mechanism modeling software, it can be used for the design and simulation of the pipe network control system. This embodiment adopts a method for obtaining the flow characteristics of the sleeve valve based on the combination of limited experimental data and flow field simulation analysis. Referring to the flowchart of a flow characteristics acquisition method shown in Figure 4, the detailed specific steps are as follows:

Step 1. After selecting the sleeve valve model, establish a three-dimensional model. Specifically, analyze the physical structure of the actual test pipeline network and construct a three-dimensional pipeline network model through three-dimensional modeling software.

Step 2, configure the flow field simulation model. Specifically, import the built three-dimensional pipe network model into the finite element analysis pre-processing software to perform flow field modeling and draw the grid to obtain the simulation model (corresponding to the above-mentioned valve flow field simulation model).

Step 3, according to the actual test parameters, set the boundary conditions, number of iterations, convergence index and other preset parameters for the simulation model (corresponding to the above preset simulation parameters).

Step 4, conduct a flow field simulation experiment, that is, conduct a flow field simulation on the simulation model set in Step 3 to obtain the output flow (corresponding to the above simulation results).

Step.5, compare the error accuracy. Specifically, by comparing the output flow obtained in Step.4 with the actual experimental flow under the same conditions, the relative error between the two is obtained (corresponding to the above error result).

Step.6, determine whether the accuracy meets the requirements. Specifically, determine whether the relative error obtained in Step.5 meets the accuracy requirements. If not, analyze the reasons and modify the simulation model, that is, perform model correction. The reasons why the accuracy does not meet the requirements may be related to the construction details of the three-dimensional model or the mesh division of the simulation model. The specific reasons need to be analyzed in detail. If the accuracy requirements are met, repeat the steps from Step.2 to Step.5 until the accuracy no longer meets the requirements or the number of test points is sufficient to prove the accuracy range of the model. It should be noted that if only the valve pressure ratio changes and the valve opening remains unchanged, there is no need to reset the mesh generation. If the valve opening changes, the mesh needs to be regenerated because the change in the valve opening will cause the shape of the flow field to change. The change in the valve pressure ratio usually requires changing the boundary condition settings in this step. That is to say, if both the valve pressure ratio and the valve opening change, Step.2 and Step.3 will usually change each time the execution is repeated.

Step 7, conduct flow field simulation test according to equidistant valve opening and valve pressure ratio; specifically, after determining that the constructed simulation model meets the accuracy requirements under different boundary conditions, flow field simulation can be conducted at openings of 10°, 20°, ..., 90° and pressure ratios of 0.1, 0.2, ..., 0.9, respectively, to obtain an equidistant two-dimensional interpolation table of output flow at different openings and different pressure ratios;

Step 8, obtain the valve flow coefficient under the equidistant valve pressure and valve opening by calculation. Specifically, the output flow equidistant two-dimensional interpolation table obtained in Step 7 is calculated by formula (1) to obtain the flow coefficient two-dimensional interpolation table of the target sleeve valve.

Step.9, obtain the complete sleeve valve flow characteristics through the extrapolation algorithm. Specifically, the two-dimensional interpolation table of flow coefficient obtained in Step.8 is extrapolated to fill the boundary parameters and substituted into the software Matlab/Simulink. Specifically, it can be substituted into the look up table module in simulink. After the valve pressure ratio and opening are input, the module can output the corresponding flow. The mechanism model of the experiment is constructed with other corresponding modules. For example, the mechanism model of the experiment can be constructed with modules such as signal input module, signal output module or data processing module. Of course, the required modules such as data preprocessing module can also be added according to actual needs; the mechanism model can be understood as the entire simulation verification platform model, which is used to verify and compare the error between the valve flow calculated by the valve flow characteristics obtained by this method and the actual test flow. And the input during the actual test is used as the simulation input signal for simulation to obtain the simulation flow output curve. Note that in order to effectively verify, the actual flow data used in this step should be distinguished from the actual flow data used for the previous test.

It should be noted that the simulated flow value obtained in Step 4 is obtained using flow simulation software and is the result of CFD calculation. The simulated flow curve obtained in Step 9 is output and calculated using the lookup table module in simulink. The former is used to obtain the control valve flow characteristic table, and the latter is used to verify the control valve flow characteristic table.

The flow rate of the regulating valve under different pressure ratios and openings is calculated by flow field simulation software, and the flow characteristic table of the regulating valve is calculated based on this. In order to verify the accuracy of this flow characteristic table, it is imported into the look up table module in simulink and forms a verification and comparison platform with other auxiliary modules. Then, the pressure ratio and opening of the actual test are used as input, and the corresponding flow characteristics are output through the look up table module, and then the valve output flow is calculated. This valve output flow is the simulation flow output curve in Step 9.

Step.10, compare and analyze the simulated flow output curve obtained in Step.9 with the actual test flow output curve, determine the relative error range and draw conclusions.

The above method provides a general method for obtaining the flow characteristics of sleeve valves when the test data is limited. This method combines the advantages of data processing and flow field simulation, reduces the dependence on the number of test data while ensuring accuracy, and improves the efficiency of obtaining flow characteristics.

The above method is further illustrated by an actual example. First, referring to the schematic diagram of a three-dimensional flow field simulation model of a sleeve valve shown in FIG5 , a three-dimensional flow field simulation model of the sleeve valve is established in Solidworks software according to the actual working environment of the sleeve valve of this model.

As shown in FIG5 , this embodiment is a two-way airflow mixing test, in which the airflow in pipeline 1 is controlled by a sleeve valve, the airflow in pipeline 2 is known, and the airflows in pipeline 1 and pipeline 2 are mixed in the mixer and enter pipeline 3. Therefore, the gas flow in pipeline 3 is the output gas flow, and the output gas flow in pipeline 3 can be indirectly controlled by controlling the front-to-back pressure ratio and valve opening of the sleeve valve in pipeline 1.

The following briefly describes the flow comparison and verification process of the test point using a sleeve valve flow test as an example.

Step.1, select the verification data as shown in Table 1

Table 1 Verification data

Step 2, calculate the displacement of the valve core of the sleeve valve according to formula (1) and the valve opening data, and configure it accordingly in the three-dimensional model. This calculation process can be converted manually or automatically calculated by the program. This is a mapping between the opening and the flow hole area. Among them, the full closing of the flow hole corresponds to an opening of 0, and the full opening of the flow hole corresponds to an opening of 90.

Step 3, perform flow field related settings in the flow field simulation software, including boundary condition setting, target setting, and local initial grid setting.

Step 4, perform simulation calculation to obtain the simulated flow of the flow tube, that is, the simulated flow on the output side of the sleeve valve of pipeline 1. Since the flow of pipeline 2 is known, the output of pipeline 1 can be obtained by subtracting the input of pipeline 2 from the output of pipeline 3.

The flow rate through the flow tube obtained by the above flow field simulation calculation is 48.87kg/s, and the relative error with the actual measured flow rate is

Thus, the flow comparison verification of a test point is completed. In order to further verify the credibility of the three-dimensional flow field simulation model of the sleeve valve, a total of 10 groups of points that meet the verification conditions are selected from several actual tests for flow field simulation verification. According to the steps described above, the flow field simulation is carried out, and the error comparison between the simulated output flow and the actual test output flow is shown in Table 2.

Table 2 Sleeve valve simulation model verification results

It can be seen from the error data in Table 2 that the relative error between the simulated flow output and the actual output does not exceed 6%, and its accuracy is acceptable for the pipe network control system. Therefore, this three-dimensional flow field model can be used to obtain the flow characteristics of the sleeve valve. It should be noted that the actual acceptable relative error threshold can be determined according to actual needs. For example, the relative error threshold can be 8%.

The following flow field simulation model based on the sleeve valve is simulated by setting the flow field simulation conditions with the sleeve valve openings of 10°, 20°, 30°, 40°, 50°, 60°, 70°, 80° and 90°, and the sleeve valve pressure ratios of 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 and 0.9. The flow field simulation results and the corresponding flow coefficients calculated by formula (1) based on the simulation results are shown in Table 3 (only the results of openings of 10° and 90° are given). The interpolation table of the flow characteristics obtained by flow field simulation with respect to the sleeve valve pressure ratio and opening is shown in Table 4. The data in Table 4 are the flow coefficients corresponding to different Vp and Pr. The flow coefficients can be used to calculate the output flow, thereby directly calculating the corresponding output flow through the input pressure ratio and opening. The complete sleeve valve flow coefficient interpolation table obtained by numerical calculation is shown in Table 5. The last row in Table 5 is all 0 because there is no gas flow when the pressure ratio is 1, so it is forcibly set to 0, and the other added data are obtained by linear interpolation. The most marginal data are generally not used in actual simulation, so the accuracy requirement can be relatively low.

Table 3 Sleeve valve flow simulation verification results

Table 4 Interpolation table of flow characteristics of sleeve valve

Table 5 Interpolation table of complete flow characteristics of sleeve valve

Referring to the schematic diagram of the flow coefficient changing with the pressure ratio and the opening shown in FIG6, the interpolation surface is generated by the matlab software. FIG6 can intuitively show the flow coefficient of the sleeve valve changing with the pressure ratio and the opening. At this point, a complete sleeve valve flow characteristic interpolation table is obtained, which can be directly used for Simulink software simulation.

Data from two actual tests were selected for verifying the technical effect of the method. By building a simulation platform, the actual test output was compared with the simulation test output to obtain a flow output comparison analysis diagram and a flow relative error analysis diagram. Specifically, see the first flow test output comparison diagram shown in Figure 7, the first flow test relative error analysis diagram shown in Figure 8, the second flow test output comparison diagram shown in Figure 9, and the second flow test relative error analysis diagram shown in Figure 10.

As shown in Figures 7 and 9, the output curve of the simulated flow rate is roughly consistent with the output curve of the actual test flow rate, with only a small deviation at the sudden change of flow rate, and the steady-state error is basically negligible. Figures 8 and 10 respectively show the relative error between the simulated flow rate and the actual test flow rate in the two tests. It can be seen from the figures that the relative error of the flow rate in the first verification test is generally below 6%, and the local maximum value does not exceed 8%, which meets the requirements of engineering applications.

The above method provides a method for obtaining a sleeve valve flow coefficient with higher accuracy when the test data is limited; it reduces the dependence on the amount of test data while ensuring accuracy; after obtaining more test data in the future, the model accuracy can be further improved based on more test data. Therefore, this method has the characteristic of being continuously strengthened as the data completeness improves.

An embodiment of the present invention provides a flow coefficient determination device, as shown in Figure 11, the device includes: a receiving module 110, used to receive a simulation instruction issued by a user; a simulation module 111, used to simulate a preset valve flow field simulation model based on the simulation instruction and preset simulation parameters to obtain a simulation result; a calculation module 112, used to calculate an error result based on the simulation result and a preset experimental result; a first determination module 113, used to continue to execute the step of receiving the simulation instruction issued by the user if the error result meets the preset result, until the preset condition is met to obtain the final valve flow field simulation model; a second determination module 114, used to determine the flow coefficient based on the final valve flow field simulation model and preset simulation parameters.

After receiving the simulation instruction issued by the user, the above-mentioned flow coefficient determination device can simulate the preset valve flow field simulation model based on the simulation instruction and the preset simulation parameters, and calculate the error result based on the obtained simulation result and the preset experimental result; if the error result meets the preset result, continue to execute the step of receiving the simulation instruction issued by the user until the preset condition is met, and the final valve flow field simulation model is obtained, and the flow coefficient is determined based on the final valve flow field simulation model and the preset simulation parameters. This method can determine the flow coefficient based on the final valve flow field simulation model and the preset simulation parameters, and only a limited number of experimental data are needed to obtain the final valve flow field simulation model that meets the accuracy requirements, thereby reducing the requirements for the number of experimental data, and while obtaining the flow coefficient that meets the accuracy requirements, the efficiency of obtaining the flow coefficient is improved.

Furthermore, it also includes a valve flow field simulation model determination module, which is used to: receive a model building instruction issued by a user; build a valve three-dimensional model according to the model building instruction; receive a model import instruction and preset import parameters issued by the user; based on the model import instruction and the preset import parameters, input the valve three-dimensional model into the preset simulation software to obtain a valve flow field simulation model corresponding to the valve three-dimensional model.

Furthermore, the preset conditions include: the error result does not meet the preset result, or the number of error results reaches a preset number.

Furthermore, the simulation parameters include multiple groups, each group of simulation parameters includes a valve opening data and a valve pressure ratio, wherein the valve pressure ratio includes: the ratio of the valve's post-valve pressure to the valve's pre-valve pressure; the second determination module is also used to: for each group of simulation parameters, determine the simulation flow corresponding to the group of simulation parameters based on the final valve flow field simulation model and the group of simulation parameters; determine the flow coefficient corresponding to the group of simulation parameters based on the simulation flow corresponding to the group of simulation parameters; determine the flow coefficient set based on the flow coefficient corresponding to each group of simulation parameters.

Furthermore, the second determination module is also used to: perform interpolation processing on the flow coefficient set to obtain a processed flow coefficient set; input the processed flow coefficient set and preset input parameters into a preset simulation verification model to obtain an output result.

The flow coefficient determination device provided in the embodiment of the present invention has the same implementation principle and technical effects as those of the aforementioned flow coefficient determination method embodiment. To briefly describe the parts not mentioned in the flow coefficient determination device embodiment, reference may be made to the corresponding contents in the aforementioned flow coefficient determination method embodiment.

An embodiment of the present invention further provides an electronic device, as shown in FIG. 12 , the electronic device includes a processor 130 and a memory 131 , the memory 131 stores machine executable instructions that can be executed by the processor 130 , and the processor 130 executes the machine executable instructions to implement the above-mentioned flow coefficient determination method.

Furthermore, the electronic device shown in FIG. 12 further includes a bus 132 and a communication interface 133 , and the processor 130 , the communication interface 133 and the memory 131 are connected via the bus 132 .

Among them, the memory 131 may include a high-speed random access memory (RAM), and may also include a non-volatile memory (non-volatile memory), such as at least one disk storage. The communication connection between the system network element and at least one other network element is realized through at least one communication interface 133 (which can be wired or wireless), and the Internet, wide area network, local area network, metropolitan area network, etc. can be used. The bus 132 can be an ISA bus, a PCI bus or an EISA bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one bidirectional arrow is used in Figure 12, but it does not mean that there is only one bus or one type of bus.

The processor 130 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by the hardware integrated logic circuit or software instructions in the processor 130. The above processor 130 can be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present invention can be implemented or executed. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in conjunction with the embodiments of the present invention can be directly embodied as a hardware decoding processor for execution, or a combination of hardware and software modules in the decoding processor for execution. The software module may be located in a storage medium mature in the art, such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, etc. The storage medium is located in the memory 131, and the processor 130 reads the information in the memory 131 and completes the steps of the method of the above embodiment in combination with its hardware.

An embodiment of the present invention also provides a machine-readable storage medium, which stores machine-executable instructions. When the machine-executable instructions are called and executed by a processor, the machine-executable instructions prompt the processor to implement the above-mentioned flow coefficient determination method. The specific implementation can be found in the method embodiment, which will not be repeated here.

The computer program product of the flow coefficient determination method, device and electronic device provided in the embodiments of the present invention includes a computer-readable storage medium storing program code, and the instructions included in the program code can be used to execute the method described in the previous method embodiment. The specific implementation can be found in the method embodiment, which will not be repeated here.

If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims (6)

1. A method of flow coefficient determination, the method comprising:

receiving a simulation instruction sent by a user;

Based on the simulation instruction and preset simulation parameters, performing simulation processing on a preset valve flow field simulation model to obtain a simulation result;

Calculating an error result based on the simulation result and a preset experimental result; wherein, the simulation result comprises: the output flow of the valve; the preset experimental result is an actual experimental flow result under the same condition as the simulation process; the error result is a relative error between the simulation result and a preset experiment result;

If the error result accords with the preset result, continuing to execute the step of receiving the simulation instruction sent by the user until the preset condition is reached, and obtaining a final valve flow field simulation model; the preset conditions include: the error result does not accord with the preset result, or the number of the error results reaches a preset number;

determining the flow coefficient based on the final valve flow field simulation model and preset simulation parameters;

The simulated parameters include a plurality of sets, each set of simulated parameters including a valve opening data and a valve pressure ratio, wherein the valve pressure ratio includes: the ratio of the valve post-valve pressure to the valve pre-valve pressure of the valve;

the step of determining the flow coefficient based on the final valve flow field simulation model and preset simulation parameters comprises the following steps:

determining simulation flow corresponding to each group of simulation parameters based on the final valve flow field simulation model and the group of simulation parameters;

Determining flow coefficients corresponding to the set of simulation parameters based on the simulation flow corresponding to the set of simulation parameters;

and determining a flow coefficient set based on the flow coefficients corresponding to each group of simulation parameters.

2. The method of claim 1, wherein the predetermined valve flow field simulation model is determined by:

receiving a model construction instruction sent by a user;

Constructing a valve three-dimensional model according to the model construction instruction;

Receiving a model import instruction and preset import parameters sent by a user;

And inputting the valve three-dimensional model into preset simulation software based on the model import instruction and preset import parameters to obtain a valve flow field simulation model corresponding to the valve three-dimensional model.

3. The method according to claim 1, wherein the method further comprises:

Performing interpolation processing on the flow coefficient set to obtain a processed flow coefficient set;

and inputting the processed flow coefficient set and preset input parameters into a preset simulation verification model to obtain an output result.

4. A flow coefficient determination device, the device comprising:

The receiving module is used for receiving a simulation instruction sent by a user;

The simulation module is used for carrying out simulation processing on a preset valve flow field simulation model based on the simulation instruction and preset simulation parameters to obtain a simulation result;

The calculation module is used for calculating an error result based on the simulation result and a preset experiment result; wherein, the simulation result comprises: the output flow of the valve; the preset test result is an actual experimental flow result under the same condition as the simulation process; the error result is a relative error between the simulation result and a preset experiment result;

The first determining module is used for continuously executing the step of receiving the simulation instruction sent by the user if the error result accords with the preset result until the preset condition is reached, so as to obtain a final valve flow field simulation model; the preset conditions include: the error result does not accord with the preset result, or the number of the error results reaches a preset number;

the second determining module is used for determining the flow coefficient based on the final valve flow field simulation model and preset simulation parameters;

The simulated parameters include a plurality of sets, each set of simulated parameters including a valve opening data and a valve pressure ratio, wherein the valve pressure ratio includes: the ratio of the valve post-valve pressure to the valve pre-valve pressure of the valve;

The second determining module is further configured to:

determining simulation flow corresponding to each group of simulation parameters based on the final valve flow field simulation model and the group of simulation parameters;

Determining flow coefficients corresponding to the set of simulation parameters based on the simulation flow corresponding to the set of simulation parameters;

and determining a flow coefficient set based on the flow coefficients corresponding to each group of simulation parameters.

5. The apparatus of claim 4, wherein the apparatus further comprises: a valve flow field simulation model determining module;

The valve flow field simulation model determining module is used for: receiving a model construction instruction sent by a user;

Constructing a valve three-dimensional model according to the model construction instruction;

Receiving a model import instruction and preset import parameters sent by a user;

And inputting the valve three-dimensional model into preset simulation software based on the model import instruction and preset import parameters to obtain a valve flow field simulation model corresponding to the valve three-dimensional model.

6. An electronic device comprising a processor and a memory, the memory storing machine executable instructions executable by the processor, the processor executing the machine executable instructions to implement the flow coefficient determination method of any of claims 1-3.