Method for rapidly predicting performance of check valve based on specified input data

Abstract

The invention provides a method for rapidly predicting the performance of a check valve based on specified input data. The method comprises the steps that the inlet total pressure, the inlet static pressure, the diameter and the sectional area of the check valve are obtained; obtaining a flow coefficient of the check valve according to the incompressible loss coefficient and the diameter of the check valve, and obtaining a loss coefficient between an inlet and an outlet of the check valve according to the flow coefficient and the sectional area of the check valve; the reference area of the check valve is obtained according to the flow coefficient, and the Mach number under the reference area is obtained according to the inlet total pressure and the inlet static pressure; according to the reference area, the Mach number under the reference area and the total pressure at the inlet, the mass flow at the outlet of the check valve is obtained; obtaining the total pressure at the outlet of the check valve according to the mass flow and the total pressure at the inlet; and obtaining the pressure drop of the check valve according to the total pressure at the inlet and the total pressure at the outlet of the check valve. According to the prediction method provided by the invention, the performance prediction of the check valve is quicker, and the demand on high-performance computing resources is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of check valve design, and in particular to a method for quickly predicting check valve performance based on specified input data. Background Art

[0002] In industrial fluid systems, check valves are key components that prevent fluid from flowing in reverse. To ensure that their performance meets specific operating requirements, engineers usually use CFD (computational fluid dynamics) software for 3D modeling and simulation. However, this approach has several significant disadvantages:

[0003] High complexity: Building accurate 3D models requires a lot of time and expertise.

[0004] Large resource consumption: High-performance computing equipment is essential for processing large-scale numerical simulations, which increases hardware costs.

[0005] Long calculation cycle: Every time the design parameters or working conditions are modified, the simulation needs to be rerun, which slows down the project progress.

[0006] Existing solutions: There are some simplified forecasting tools on the market, but they often sacrifice accuracy for speed and cannot meet the needs of both efficiency and accuracy. Summary of the invention

[0007] In view of the problems existing in the above-mentioned background technology, the present invention provides a method for quickly predicting the performance of a check valve based on specified input data, so as to simplify the design process and improve efficiency.

[0008] To achieve the above object, the present invention adopts the following technical solution:

[0009] The present invention provides a method for quickly predicting the performance of a check valve based on specified input data, comprising the following process:

[0010] Obtain the total inlet pressure, inlet static pressure, diameter and cross-sectional area of ​​the check valve;

[0011] The flow coefficient of the check valve is obtained according to the incompressible loss coefficient and the diameter of the check valve, and the loss coefficient between the inlet and the outlet of the check valve is obtained according to the flow coefficient and the cross-sectional area of ​​the check valve;

[0012] A reference area of ​​the check valve is obtained according to the flow coefficient, and a Mach number under the reference area is obtained according to the total pressure at the inlet and the static pressure at the inlet;

[0013] Obtaining a mass flow rate at an outlet of the check valve according to the reference area, the Mach number under the reference area, and the total pressure at the inlet;

[0014] Obtaining the total pressure at the check valve outlet according to the mass flow and the total pressure at the inlet;

[0015] The pressure drop of the check valve is obtained according to the total pressure at the inlet of the check valve and the total pressure at the outlet.

[0016] As a further illustration of the present invention, the incompressible loss coefficient The calculation formula is as follows:

[0017] ;

[0018] in, Is the original factory loss coefficient of the check valve;

[0019] Correction factor for:

[0020] ;

[0021] Where: K is the loss coefficient at the current Reynolds number, is the loss coefficient when the Reynolds number is 10000, K and Obtained according to the Reynolds number-loss coefficient characteristic curve.

[0022] As a further explanation of the present invention, the process of obtaining the Reynolds number-loss coefficient characteristic curve specifically includes:

[0023] Build a fluid circulation system including a check valve;

[0024] Gradually change the flow rate through the check valve and record the mass flow rate, dynamic viscosity of the fluid and pressure drop at each flow point;

[0025] Calculating the Reynolds number according to the recorded mass flow rate and the dynamic viscosity;

[0026] Calculating a loss coefficient based on the recorded pressure drop and mass flow rate;

[0027] The Reynolds number and the corresponding loss coefficient at different flow points are plotted to obtain the Reynolds number-loss coefficient characteristic curve.

[0028] As a further illustration of the present invention, the calculation formula of the Reynolds number and the loss coefficient at each flow point is:

[0029] The Reynolds number Re is:

[0030] ;

[0031] Among them, ρ is the density of the fluid, v is the velocity of the fluid, D is the diameter of the check valve, and μ is the dynamic viscosity of the fluid;

[0032] Loss coefficient:

[0033] ;

[0034] Where ΔP is the pressure drop across the check valve, ρ is the density of the fluid, and v is the velocity of the fluid;

[0035] Velocity of the fluid:

[0036] ;

[0037] Where m is the mass flow rate and A is the cross-sectional area of ​​the check valve.

[0038] As a further illustration of the present invention, the flow coefficient of the check valve The calculation formula is as follows:

[0039] ;

[0040] Where D is the diameter of the check valve. is the incompressible loss coefficient.

[0041] As a further illustration of the present invention, the loss coefficient between the inlet and outlet of the check valve is The calculation formula is:

[0042] ;

[0043] Where A is the cross-sectional area of ​​the check valve, Flow coefficient of the check valve

[0044] As a further illustration of the present invention, the reference area The calculation formula is:

[0045] ;

[0046] Where γ is the adiabatic index, is the flow coefficient, is the gas flow coefficient, for Mach number at the gas flow coefficient;

[0047] Mach number for the reference area The calculation formula is:

[0048] ;

[0049] in, is the total pressure at the inlet, is the static pressure at the inlet.

[0050] As a further illustration of the present invention, the mass flow rate at the check valve outlet is The calculation formula is:

[0051] ;

[0052] in, is the Mach number under the reference area, is the total pressure at the inlet, is the reference area, Z is the compressibility factor, R is the universal gas constant, T is the gas temperature at the inlet, and γ is the adiabatic index.

[0053] As a further illustration of the present invention, the total pressure at the check valve outlet The following formula is used to calculate:

[0054] ;

[0055] in, is the total pressure at the inlet, is the mass flow rate at the outlet, is the weight coefficient.

[0056] As a further illustration of the present invention, the pressure drop ΔP of the check valve = the total pressure at the outlet -Total pressure at inlet .

[0057] Compared with the prior art, the present invention has the following beneficial technical effects:

[0058] The prediction method provided by the present invention can quickly calculate the performance parameters such as the pressure drop of the check valve, the loss coefficient between the inlet and the outlet, etc. by giving input parameters, and reduce the calculation time by optimizing the algorithm, so that the performance prediction of the check valve becomes faster, while ensuring that the prediction results have high accuracy, reducing the demand for high-performance computing resources, thereby reducing the overall cost.

[0059] Other features and advantages of the technical solution will be described in the subsequent description, and partly become apparent from the description, or understood by implementing the technical solution. The purpose and other advantages of the technical solution can be achieved and obtained through the structures specifically pointed out in the written description and the drawings.

[0060] The technical solution of the present technical solution is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] The accompanying drawings are used to provide a further understanding of the technical solution and constitute a part of the specification. Together with the embodiments of the technical solution, they are used to explain the technical solution and do not constitute a limitation of the technical solution. In the accompanying drawings:

[0062] Figure 1 A flow chart of a method for quickly predicting check valve performance based on specified input data provided by the present invention. DETAILED DESCRIPTION

[0063] The preferred embodiments of the present technical solution are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present technical solution, and are not used to limit the present technical solution.

[0064] like Figure 1 As shown, the present invention provides a method for quickly predicting the performance of a check valve based on specified input data, comprising the following steps:

[0065] Step 1: Obtain input parameters such as the inlet total pressure, inlet static pressure, diameter, and cross-sectional area of ​​the check valve.

[0066] Step 2: Obtain the flow coefficient of the check valve according to the incompressible loss coefficient and the diameter of the check valve, and obtain the loss coefficient between the inlet and outlet of the check valve according to the flow coefficient and the cross-sectional area of ​​the check valve.

[0067] Incompressible loss coefficient The calculation formula is as follows:

[0068] ;

[0069] in, Is the original factory loss coefficient of the check valve;

[0070] Correction factor for:

[0071] ;

[0072] Where: K is the loss coefficient at the current Reynolds number, is the loss coefficient when the Reynolds number is 10000, K and Obtained according to the Reynolds number-loss coefficient characteristic curve.

[0073] The process of obtaining the Reynolds number-loss coefficient characteristic curve specifically includes the following steps:

[0074] Step 101: Build a fluid circulation system including a check valve. The fluid circulation system can use an existing fluid testing device as long as the system includes a check valve, and configure pressure sensors, temperature sensors, flow meters and other measuring equipment in the system.

[0075] Step 102: gradually change the flow rate through the check valve, and record the mass flow rate, dynamic viscosity and pressure drop of the fluid at each flow point.

[0076] It should be noted that the measurement is repeated several times at each flow point to ensure the consistency and accuracy of the data. During the measurement process, a constant inlet temperature needs to be set and maintained, and the inlet pressure of the system needs to be stable.

[0077] Step 103: Calculate the Reynolds number based on the recorded mass flow rate and dynamic viscosity.

[0078] The calculation formula for the Reynolds number and loss coefficient at each flow point is:

[0079] The Reynolds number Re is:

[0080] ;

[0081] Among them, ρ is the density of the fluid, v is the velocity of the fluid, D is the diameter of the check valve, and μ is the dynamic viscosity of the fluid;

[0082] Velocity of the fluid:

[0083] ;

[0084] Where m is the mass flow rate and A is the cross-sectional area of ​​the check valve.

[0085] Step 104: Calculate the loss coefficient based on the recorded pressure drop and mass flow rate;

[0086] Loss coefficient:

[0087] ;

[0088] Where ΔP is the pressure drop across the check valve, ρ is the density of the fluid, and v is the velocity of the fluid;

[0089] Velocity of the fluid:

[0090] ;

[0091] Where m is the mass flow rate and A is the cross-sectional area of ​​the check valve.

[0092] Step 105: Plot the Reynolds number and the corresponding loss coefficient at different flow points to obtain a Reynolds number-loss coefficient characteristic curve.

[0093] It should be noted that in order to improve the reliability of the data, the experiment can be repeated under different conditions.

[0094] Flow coefficient of check valve The calculation formula is as follows:

[0095] ;

[0096] Where D is the diameter of the check valve. is the incompressible loss coefficient.

[0097] Loss coefficient between the inlet and outlet of the check valve The calculation formula is:

[0098] ;

[0099] Where A is the cross-sectional area of ​​the check valve, Flow coefficient of the check valve

[0100] Step 3: Obtain the reference area of ​​the check valve based on the flow coefficient, and obtain the Mach number under the reference area based on the total pressure at the inlet and the static pressure at the inlet.

[0101] Reference area The calculation formula is:

[0102] ;

[0103] Where γ is the adiabatic index, is the flow coefficient, is the gas flow coefficient, for Mach number at the gas flow coefficient; reference area is the area of ​​a specified cross section, such as any section in the nozzle or a section after the throat.

[0104] Mach number at reference area The calculation formula is:

[0105] ;

[0106] in, is the total pressure at the inlet, which refers to the state of the fluid at the inlet, that is, the pressure when the fluid is completely isentropically decelerated to a stationary state. is the static pressure at the inlet.

[0107] Step 4: Based on the reference area, the Mach number under the reference area and the total pressure at the inlet, obtain the mass flow rate at the check valve outlet.

[0108] Mass flow at the check valve outlet The calculation formula is:

[0109] ;

[0110] in, is the Mach number under the reference area, is the total pressure at the inlet, is the reference area, Z is the compressibility factor, which is used to describe the deviation between the real gas and the ideal gas behavior. R is the universal gas constant, a constant used to describe the ideal gas state equation. T is the gas temperature at the inlet. γ is the adiabatic index, which refers to the ratio of the specific heat capacity at constant pressure to the specific heat capacity at constant volume of the gas, usually 1.4 for air.

[0111] Step 5: Obtain the total pressure at the check valve outlet based on the mass flow rate and the total pressure at the inlet.

[0112] Total pressure at check valve outlet The following formula is used to calculate:

[0113] ;

[0114] in, is the total pressure at the inlet, is the mass flow rate at the outlet, is the weight coefficient, which can be calculated based on parameters such as the circulation coefficient.

[0115] Step 6: According to the total pressure at the inlet and outlet of the check valve, the pressure drop of the check valve is obtained. The pressure drop of the check valve ΔP = the total pressure at the outlet -Total pressure at inlet .

[0116] According to the above prediction process, the performance parameters of the check valve, pressure drop and loss coefficient between the inlet and outlet, can be quickly obtained. The present invention reduces the calculation time by optimizing the algorithm, making the check valve performance prediction faster, while ensuring that the prediction results have high accuracy, reducing the demand for high-performance computing resources, and thus reducing the overall cost.

[0117] Obviously, those skilled in the art can make various changes and modifications to the technical solution without departing from the spirit and scope of the technical solution. Thus, if these modifications and variations of the technical solution fall within the scope of the claims of the technical solution and their equivalents, the technical solution is also intended to include these modifications and variations.

Claims

1. A method for quickly predicting check valve performance based on specified input data, characterized in that: include: Obtain the total inlet pressure, inlet static pressure, diameter and cross-sectional area of ​​the check valve; The flow coefficient of the check valve is obtained according to the incompressible loss coefficient and the diameter of the check valve, and the loss coefficient between the inlet and the outlet of the check valve is obtained according to the flow coefficient and the cross-sectional area of ​​the check valve; A reference area of ​​the check valve is obtained according to the flow coefficient, and a Mach number under the reference area is obtained according to the total pressure at the inlet and the static pressure at the inlet; Obtaining a mass flow rate at an outlet of the check valve according to the reference area, the Mach number under the reference area, and the total pressure at the inlet; Obtaining the total pressure at the check valve outlet according to the mass flow and the total pressure at the inlet; The pressure drop of the check valve is obtained according to the total pressure at the inlet of the check valve and the total pressure at the outlet.

2. The method for quickly predicting check valve performance based on specified input data according to claim 1, characterized in that: The incompressible loss coefficient The calculation formula is as follows: ； in, Is the original factory loss coefficient of the check valve; Correction factor for: ； Where: K is the loss coefficient at the current Reynolds number, is the loss coefficient when the Reynolds number is 10000, K and Obtained according to the Reynolds number-loss coefficient characteristic curve.

3. The method for quickly predicting check valve performance based on specified input data according to claim 2, characterized in that: The process of obtaining the Reynolds number-loss coefficient characteristic curve specifically includes: Build a fluid circulation system including a check valve; Gradually change the flow rate through the check valve and record the mass flow rate, dynamic viscosity of the fluid and pressure drop at each flow point; Calculating the Reynolds number according to the recorded mass flow rate and the dynamic viscosity; Calculating a loss coefficient based on the recorded pressure drop and mass flow rate; The Reynolds number and the corresponding loss coefficient at different flow points are plotted to obtain the Reynolds number-loss coefficient characteristic curve.

4. The method for quickly predicting check valve performance based on specified input data according to claim 3, characterized in that: The calculation formula of the Reynolds number and the loss coefficient at each flow point is: The Reynolds number Re is: ； Among them, ρ is the density of the fluid, v is the velocity of the fluid, D is the diameter of the check valve, and μ is the dynamic viscosity of the fluid; Loss coefficient: ； Where ΔP is the pressure drop across the check valve, ρ is the density of the fluid, and v is the velocity of the fluid; Velocity of the fluid: ； Where m is the mass flow rate and A is the cross-sectional area of ​​the check valve.

5. The method for quickly predicting check valve performance based on specified input data according to claim 2, characterized in that: The flow coefficient of the check valve The calculation formula is as follows: ； Where D is the diameter of the check valve. is the incompressible loss coefficient.

6. The method for quickly predicting check valve performance based on specified input data according to claim 5, characterized in that: The loss coefficient between the inlet and outlet of the check valve The calculation formula is: ； Where A is the cross-sectional area of ​​the check valve, Flow coefficient of the check valve.

7. The method for quickly predicting check valve performance based on specified input data according to claim 5, characterized in that: The reference area The calculation formula is: ； Where γ is the adiabatic index, is the flow coefficient, is the gas flow coefficient, for Mach number at the gas flow coefficient; Mach number for the reference area The calculation formula is: ； in, is the total pressure at the inlet, is the static pressure at the inlet.

8. The method for quickly predicting check valve performance based on specified input data according to claim 7, characterized in that: The mass flow rate at the check valve outlet The calculation formula is: ； in, is the Mach number under the reference area, is the total pressure at the inlet, is the reference area, Z is the compressibility factor, R is the universal gas constant, T is the gas temperature at the inlet, and γ is the adiabatic index.

9. The method for quickly predicting check valve performance based on specified input data according to claim 8, characterized in that: The total pressure at the check valve outlet The following formula is used to calculate: ； in, is the total pressure at the inlet, is the mass flow rate at the outlet, is the weight coefficient.

10. The method for quickly predicting check valve performance based on specified input data according to claim 1, characterized in that: The pressure drop of the check valve ΔP = total pressure at the outlet -Total pressure at inlet .

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