A method for calculating the flow coefficient of pseudoplastic power-law fluid control valve

Abstract

The present invention relates to the technical field of control valve flow coefficient calculation, and specifically to a method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve. First, based on the selected control valve and the type of pseudoplastic power-law fluid flowing through the control valve, basic process parameters are determined. Next, the Reynolds number, which is a key indicator for evaluating the flow characteristics of the fluid, is calculated using these basic process parameters and the constitutive equation of the pseudoplastic power-law fluid. Then, the equivalent friction coefficient is further calculated in combination with the Reynolds number and the basic process parameters to reflect the flow resistance of the fluid in the control valve. On this basis, the Reynolds number correction coefficient and the pressure drop are calculated by the Reynolds number and the equivalent friction coefficient, so as to more accurately describe the flow state of the fluid in the control valve.

Description

Technical Field

[0001] The invention relates to the technical field of control valve flow coefficient calculation, in particular to a method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve. Background Art

[0002] As an indicator of the flow capacity of a control valve, the flow coefficient is crucial in the performance evaluation of the control valve. At present, the general flow coefficient calculation formula is only applicable to Newtonian fluids, but not to non-Newtonian fluids.

[0003] The shear stress of Newtonian fluids is linearly related to the shear deformation rate, while the shear stress of non-Newtonian fluids is nonlinearly related to the shear rate. In industrial applications, most non-Newtonian fluids are pseudoplastic fluids, also known as shear-thinning fluids, whose apparent viscosity decreases with increasing shear rate. Pseudoplastic fluids whose viscosity curves conform to the power law equation are also called pseudoplastic power-law fluids, such as PA6, PA66, HDPE, elastic polyethylene, pulp, industrial wastewater, etc. Pseudoplastic power-law fluids generally have a larger viscosity and a lower Reynolds number, and the effective flow coefficient of pipe fittings and pipelines will become smaller. In extreme cases, such as for highly viscous polymer melts, the flow has become a laminar state, and its flow rate is proportional to the pressure drop of the control valve, rather than proportional to the square root of the pressure drop of the control valve.

[0004] At present, there are only a few industry standards or specifications for determining the flow coefficient of non-Newtonian fluid control valves. At the same time, the use of numerical simulation to determine the flow coefficient of non-Newtonian fluid control valves has the problems of difficulty in establishing a three-dimensional simulation model of the control valve flow channel during the selection stage, high requirements for the completeness of basic data such as fluid physical parameters, large workload, and poor operability.

[0005] It can be seen that the above situation makes it difficult to calculate the flow coefficient of the control valve of non-Newtonian fluid. Therefore, it is urgent to propose a theoretical calculation method for the flow coefficient of the control valve of pseudoplastic power law fluid, a common non-Newtonian fluid. Summary of the invention

[0006] In order to avoid and overcome the technical problems existing in the prior art, the present invention provides a method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve. The present invention can effectively improve the accuracy of calculating the flow coefficient of a pseudoplastic power-law fluid control valve.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] A method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve comprises the following calculation steps:

[0009] S1. Based on the selected control valve and the type of pseudoplastic power-law fluid flowing through the control valve, determine the basic process parameters of the pseudoplastic power-law fluid flowing through the control valve;

[0010] S2. According to the basic process parameters and in combination with the constitutive equation of pseudoplastic power-law fluid, the Reynolds number of the pseudoplastic power-law fluid flowing through the control valve is calculated;

[0011] S3. Using the calculated Reynolds number and combining it with basic process parameters, calculate the equivalent friction coefficient of the pseudoplastic power law fluid flowing through the control valve;

[0012] S4. Calculate the Reynolds number correction factor and the pressure drop when the pseudoplastic power law fluid flows through the control valve by using the calculated Reynolds number and equivalent friction coefficient;

[0013] S5. Calculate the flow coefficient of the control valve when the pseudoplastic power-law fluid flows through the control valve based on the Reynolds number correction coefficient and the pressure drop.

[0014] As a further solution of the present invention: the basic process parameters include the inner diameter of the pipe of the inlet and outlet of the control valve D , Density of Pseudoplastic Power-Law Fluid ρ , Volume flow rate of pseudoplastic power-law fluid flowing through a control valve Q , shear rate of pseudoplastic power-law fluid , and the apparent viscosity corresponding to the shear rate of the pseudoplastic power law fluid .

[0015] As a further solution of the present invention: the constitutive equation of pseudoplastic power-law fluid is specifically expressed as follows:

[0016] ;

[0017] In the formula, represents the apparent viscosity of the pseudoplastic power-law fluid, in Pa·s; Represents the viscosity coefficient of pseudoplastic power law fluid, in Pa·s n ; represents the flow index of pseudoplastic power-law fluid, dimensionless; represents the shear rate of pseudoplastic power-law fluid, in s -1 ;in, and are the constitutive constants of pseudoplastic power-law fluids.

[0018] As a further solution of the present invention: the Reynolds number of the control valve is calculated by the Reynolds number calculation equation, which is specifically expressed as follows:

[0019] ;

[0020] In the formula, Re MR Reynolds number for pseudoplastic power-law fluid flowing through a control valve, dimensionless; D Indicates the inner diameter of the pipes at the inlet and outlet of the control valve; ρ It represents the density of pseudoplastic power-law fluid in kg / m 3 ; V It represents the average flow velocity of pseudoplastic power law fluid flowing through the control valve, in m / s; Q It represents the volume flow rate of pseudoplastic power law fluid flowing through the control valve, in m 3 / s.

[0021] As a further solution of the present invention: the equivalent friction coefficient of the control valve is calculated by an equivalent friction coefficient calculation equation, and the equivalent friction coefficient calculation equation is specifically expressed as follows:

[0022] ;

[0023] In the formula, It represents the equivalent friction coefficient of pseudoplastic power law fluid flowing through the control valve, dimensionless; express Re MR =1, the friction coefficient of pseudoplastic power law fluid flowing through the control valve, dimensionless; express The friction coefficient of pseudoplastic power law fluid flowing through the control valve is dimensionless.

[0024] As a further solution of the present invention: the Reynolds number correction coefficient of the control valve is calculated using the Reynolds number correction coefficient calculation equation, which is specifically expressed as follows:

[0025] ;

[0026] In the formula, F R Reynolds number correction factor for pseudoplastic power law fluid flowing through a control valve. Dimensionless.

[0027] As a further solution of the present invention: the pressure drop when the pseudoplastic power-law fluid flows through the control valve is calculated by a pressure drop calculation equation, and the pressure drop calculation equation is specifically expressed as follows:

[0028] ;

[0029] In the formula, It represents the pressure drop when a pseudoplastic power-law fluid flows through a control valve, in Pa.

[0030] As a further solution of the present invention: the flow coefficient of the control valve when the pseudoplastic power law fluid flows through the control valve is calculated using the flow coefficient calculation equation, and the flow coefficient calculation equation is specifically expressed as follows:

[0031] ;

[0032] In the formula, C V Expresses the flow coefficient of a pseudoplastic power law fluid through a control valve in gallons per minute.

[0033] As a further aspect of the present invention: Flow Index The value range is (0, 1).

[0034] As a further solution of the present invention: Reynolds number correction factor F R The value range is (0, 1).

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] 1. The present invention proposes a method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve. The method significantly improves the accuracy of the calculation through a series of precise calculation steps. First, it determines the basic process parameters based on the selected control valve and the type of pseudoplastic power-law fluid flowing through the control valve. Then, the Reynolds number, which is a key indicator for evaluating the flow characteristics of the fluid, is calculated using these parameters and the constitutive equation of the pseudoplastic power-law fluid. Then, the equivalent friction coefficient is further calculated in combination with the Reynolds number and the basic process parameters to reflect the flow resistance of the fluid in the control valve. On this basis, the Reynolds number correction coefficient and the pressure drop are calculated by the Reynolds number and the equivalent friction coefficient, so as to more accurately describe the flow state of the fluid in the control valve. Finally, based on these parameters, the flow coefficient of the control valve is accurately calculated. The method of the present invention is not only scientific and rigorous, but also highly practical, and provides strong support for the design and optimization of pseudoplastic power-law fluid control valves.

[0037] 2. The method of the present invention is applicable to the determination of the flow coefficient of the control valve whose medium is a pseudoplastic power-law fluid. The flow state of the medium can be laminar flow, transitional flow or turbulent flow, and the flow coefficient of various types and structural forms of control valves such as single-seat globe straight-through, angle type and Y-type structures, as well as gate valves, ball valves, plug valves, and butterfly valves can be determined. That is, it is not limited by the medium flow state, Reynolds number, viscosity, control valve type, structural form, nominal diameter, and nominal pressure.

[0038] 3. The Reynolds number calculation formulas for Newtonian fluids and non-Newtonian fluids are different. The Reynolds number calculation formula for pseudoplastic power-law fluids used in the present invention specifically considers the influence of rheological parameters of pseudoplastic power-law fluids such as consistency coefficient and flow index. The present invention determines the equivalent friction coefficient of the pseudoplastic power-law fluid control valve through the corresponding equation. The determination of the equivalent friction coefficient takes into account the type, structure, and size of the control valve, as well as the pseudoplastic fluid properties such as flow rate, density, viscosity, and Reynolds number, so as to determine the calculated pressure drop required for the flow coefficient of the pseudoplastic power-law fluid control valve, rather than directly using the upstream and downstream pressure difference of the control valve, thereby avoiding the distortion of the flow coefficient being too large due to the calculated pressure drop being less than the upstream and downstream pressure difference of the control valve due to failure to consider the blocked flow. For pseudoplastic power-law fluids such as polymer melts, their apparent viscosity is generally large, the Reynolds number is generally low, and the fluid flow state is generally laminar. In extreme cases, the flow rate is proportional to the calculated pressure drop of the control valve, rather than proportional to the square root of the calculated pressure drop of the control valve. Therefore, a Reynolds number correction coefficient based on pseudoplastic power-law fluid is introduced to ensure the calculation accuracy of the flow coefficient of the pseudoplastic power-law fluid control valve.

[0039] 4. The theoretical method for determining the flow coefficient of a pseudoplastic power-law fluid control valve proposed in the present invention is a program written according to the theoretical model. Only basic parameters need to be input to quickly obtain the flow coefficient of a pseudoplastic power-law fluid control valve. The calculation is simple, and the requirements for the completeness of basic data such as fluid physical parameters are not high. It has strong operability and is convenient for engineering control valve selection calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a calculation flow chart of the present invention.

[0041] Figure 2 It is a structural schematic diagram of a single-seat Globe straight-through control valve in the present invention.

[0042] Figure 3 It is the fitting curve diagram of the constitutive equation in the present invention.

[0043] Figure 4 It is a structural schematic diagram of a single-seat Globe angle control valve in the present invention.

[0044] Figure 5 It is a structural schematic diagram of a single-seat GlobeY-type control valve in the present invention.

[0045] In the figure: 1. Single-seat Globe straight-through control valve; 2. Single-seat Globe angle control valve; 3. Single-seat Globe Y-type control valve. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0047] See also Figure 1 In an embodiment of the present invention, a method for calculating a flow coefficient of a pseudoplastic power-law fluid control valve includes the following calculation steps:

[0048] 1. Based on the selected control valve and the type of pseudoplastic power-law fluid flowing through the control valve, determine the basic process parameters of the pseudoplastic power-law fluid flowing through the control valve.

[0049] The basic process parameters include the inner diameter of the pipes at the inlet and outlet of the control valve. D , Density of Pseudoplastic Power-Law Fluid ρ , Volume flow rate of pseudoplastic power-law fluid flowing through a control valve Q , the pressure before the control valve when the pseudoplastic power law fluid flows through the control valve P , the temperature of pseudoplastic power-law fluid T , shear rate of pseudoplastic power-law fluid , the apparent viscosity corresponding to the shear rate of pseudoplastic power law fluid , control valve types and their structural forms.

[0050] 2. Based on the basic process parameters and combined with the constitutive equation of pseudoplastic power-law fluid, calculate the Reynolds number when the pseudoplastic power-law fluid flows through the control valve.

[0051] The constitutive equation of pseudoplastic power-law fluid is shown in formula (1):

[0052] (1);

[0053] The apparent viscosity of the fluid medium at different shear rates can be measured by a rheometer, such as a rotational rheometer to measure the apparent viscosity at a low shear rate and a capillary rheometer to measure the apparent viscosity at a high shear rate. The apparent viscosity data of the pseudoplastic power-law fluid at different shear rates can be fitted nonlinearly using formula (1) to obtain the constitutive constant of the pseudoplastic power-law fluid: and , and the flow index The value range is (0, 1).

[0054] The Reynolds number of the control valve is calculated using the Reynolds number calculation equation shown in formula (2):

[0055] (2).

[0056] 3. Using the calculated Reynolds number and combining it with basic process parameters, calculate the equivalent friction coefficient of the pseudoplastic power-law fluid flowing through the control valve.

[0057] The equivalent friction coefficient of the control valve is calculated by the equivalent friction coefficient calculation equation shown in formula (3):

[0058] (3);

[0059] If the inner diameters of the pipes before and after the control valve are the same and the medium is an incompressible fluid, according to the Bernoulli equation, when the control valve is at a certain opening, the energy loss per unit weight of the fluid is proportional to the kinetic energy of the fluid, and the proportional coefficient is called the equivalent friction coefficient of the control valve.

[0060] When calculating, the control valves of different types and structures correspond to and , select according to Table 1.

[0061] Table 1 and Specific data table

[0062] .

[0063] 4. Calculate the Reynolds number correction factor and the pressure drop of the pseudoplastic power-law fluid flowing through the control valve using the calculated Reynolds number and equivalent friction coefficient.

[0064] The Reynolds number correction factor of the control valve is calculated using the Reynolds number correction factor calculation equation shown in formula (4):

[0065] (4);

[0066] Among them, the Reynolds number correction factor The value range is (0, 1).

[0067] The pressure drop calculation equation shown in formula (5) is used to calculate the pressure drop when the pseudoplastic power law fluid flows through the control valve:

[0068] (5).

[0069] 5. Based on the Reynolds number correction coefficient and pressure drop, calculate the flow coefficient of the control valve when the pseudoplastic power law fluid flows through the control valve.

[0070] The flow coefficient calculation equation shown in formula (6) is used to calculate the flow coefficient of the control valve when the pseudoplastic power law fluid flows through the control valve.

[0071] (6).

[0072] Embodiment 1:

[0073] In a PA66 continuous polymerization device, the flow coefficient of the PA66 melt control valve in a certain process section is calculated. The specific implementation steps are as follows:

[0074] 1. Determine the basic process parameters:

[0075] Inner diameter of pipe D is 0.04 m, the density of the pseudoplastic power law fluid ρ 977 , volume flow Q 0.2047m 3 / s, the fluid flowing through the control valve is PA66 melt, the pressure before the valve P The temperature of the pseudoplastic power law fluid is 13.8 MPa. T It is 264℃.

[0076] Pressure before valve P is 13.8MPa and the temperature of the pseudoplastic power law fluid T At 264°C, the shear rate of the pseudoplastic power-law fluid and shear viscosity The specific values ​​are divided into the following 5 groups:

[0077] =207.13 , = 58.89Pa·s;

[0078] =529.94 , = 46.33Pa·s;

[0079] =816.32 , = 42.22Pa·s;

[0080] =1022.73 , = 40.09Pa·s;

[0081] =1380.48 , = 37.65Pa·s;

[0082] The control valve type is a single-seat Globe and the structure is straight-through. The typical structure of the single-seat Globe straight-through control valve 1 used in this embodiment is as follows: Figure 2 shown.

[0083] 2. Calculate the Reynolds number:

[0084] The five shear rate groups in the basic process parameters of this embodiment are used. and shear viscosity Data, fitting formula (1), fitting curve and fitting formula see Figure 3 .according to Figure 3 The power law equation curve obtained by fitting the data in the data line is: =269.68 Pa. , flow index =0.76. It can be seen that PA66 melt is a pseudoplastic power-law fluid, that is, a non-Newtonian shear-thinning flow.

[0085] Substituting the data into formula (2) to calculate, the Reynolds number of PA66 melt flowing through the control valve can be obtained: =0.0105.

[0086] 3. Calculate the equivalent friction coefficient:

[0087] The control valve type is single-seat Globe and the structure is straight-through. According to Table 1, it can be seen that: =1500, =4. According to formula (3), the equivalent friction coefficient of PA66 melt flowing through the single-seat Globe straight-through control valve 1 can be obtained: =142845.22.

[0088] 4. Calculate the pressure drop and Reynolds number correction factor:

[0089] 4.1. Calculate the Reynolds number correction factor:

[0090] Input the data into formula (4) to calculate the Reynolds number correction coefficient when PA66 melt flows through the single-seat Globe straight-through control valve 1: =0.0117.

[0091] 4.2. Calculate the pressure drop:

[0092] Input the data into formula (5) to calculate the pressure drop of PA66 melt flowing through the single-seat Globe straight-through control valve 1: =142881.64Pa.

[0093] 5. Solve the flow coefficient:

[0094] Input the data into formula (6) to calculate the flow coefficient of PA66 melt flowing through the single-seat Globe straight-through control valve 1: =16.76.

[0095] Embodiment 2:

[0096] In a PA66 continuous polymerization device, the flow coefficient required for the selection of a PA66 melt control valve in a certain process section, the specific implementation steps include:

[0097] 1. Determine the basic process parameters:

[0098] Inner diameter of pipe D is 0.04 m, the density of pseudoplastic power law fluid ρ 977 , volume flow Q 0.2047m 3 / s, the medium flowing through the control valve is PA66 melt, the pressure before the valve P The temperature of the pseudoplastic power law fluid is 13.8 MPa. T It is 264℃.

[0099] Pressure before valve P is 13.8MPa and the temperature of the pseudoplastic power law fluid T At 264°C, the shear rate of the pseudoplastic power-law fluid and shear viscosity The specific values ​​are divided into the following 5 groups:

[0100] =207.13 , = 58.89Pa·s;

[0101] =529.94 , = 46.33Pa·s;

[0102] =816.32 , = 42.22Pa·s;

[0103] =1022.73 , = 40.09Pa·s;

[0104] =1380.48 , = 37.65Pa·s;

[0105] The control valve type is a single-seat Globe and the structure is an angle type or a Y type. The typical structure of the single-seat Globe angle control valve 2 used in this embodiment is as follows: Figure 4 As shown, the typical structure of a single-seat Globe Y-type control valve 3 is as follows Figure 5 shown.

[0106] 2. Calculate the Reynolds number:

[0107] The five shear rate groups in the basic process parameters of this embodiment are used. and shear viscosity Data, fitting formula (1), according to the fitting results can be obtained: consistency coefficient =269.68 Pa. ， Flow Index =0.76. It can be seen that PA66 melt is a pseudoplastic power-law fluid, that is, a non-Newtonian shear-thinning flow.

[0108] Substituting the data into formula (2) to calculate, the Reynolds number of PA66 melt flowing through the control valve can be obtained: =0.0105.

[0109] 3. Calculate the equivalent friction coefficient:

[0110] The control valve type is single-seat Globe and the structure is angle type. According to Table 1, it can be seen that: =1000, =2. According to formula (3), the equivalent friction coefficient of PA66 melt flowing through the single-seat Globe angle control valve 2 can be obtained: =95229.06.

[0111] 4. Calculate the pressure drop and Reynolds number correction factor:

[0112] 4.1. Calculate the Reynolds number correction factor:

[0113] Input the data into formula (4) to calculate the Reynolds number correction coefficient when PA66 melt flows through the single-seat Globe angle control valve 2: =0.0117.

[0114] 4.2. Calculate the pressure drop:

[0115] Input the data into formula (5) to calculate the pressure drop of PA66 melt when it flows through the single-seat Globe angle control valve: =95253.34Pa.

[0116] 5. Solve the flow coefficient:

[0117] Input the data into formula (6) to calculate the flow coefficient of PA66 melt flowing through the single-seat Globe angle control valve 2: =20.52.

[0118] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve, characterized in that: The calculation steps include: S1. Based on the selected control valve and the type of pseudoplastic power-law fluid flowing through the control valve, determine the basic process parameters of the pseudoplastic power-law fluid flowing through the control valve; S2. According to the basic process parameters and in combination with the constitutive equation of pseudoplastic power-law fluid, the Reynolds number of the pseudoplastic power-law fluid flowing through the control valve is calculated; S3. Using the calculated Reynolds number and combining it with basic process parameters, calculate the equivalent friction coefficient of the pseudoplastic power law fluid flowing through the control valve; S4. Calculate the Reynolds number correction factor and the pressure drop when the pseudoplastic power law fluid flows through the control valve by using the calculated Reynolds number and equivalent friction coefficient; S5. Calculate the flow coefficient of the control valve when the pseudoplastic power law fluid flows through the control valve according to the Reynolds number correction coefficient and the pressure drop; The equivalent friction coefficient of the control valve is calculated by the equivalent friction coefficient calculation equation. The equivalent friction coefficient calculation equation is specifically expressed as follows: ； In the formula, It represents the equivalent friction coefficient of pseudoplastic power law fluid flowing through the control valve, dimensionless; express Re MR =1, the friction coefficient of pseudoplastic power law fluid flowing through the control valve, dimensionless; express When , the friction coefficient of pseudoplastic power law fluid flowing through the control valve is dimensionless; Re MR Reynolds number for pseudoplastic power-law fluid flowing through a control valve, dimensionless; D Indicates the inner diameter of the pipes at the inlet and outlet of the control valve; The Reynolds number correction coefficient calculation equation is used to calculate the Reynolds number correction coefficient of the control valve. The Reynolds number correction coefficient calculation equation is specifically expressed as follows: ； In the formula, F R Reynolds number correction factor for pseudoplastic power law fluid flowing through a control valve. Dimensionless.

2. A method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve according to claim 1, characterized in that: The basic process parameters include the inner diameter of the pipes at the inlet and outlet of the control valve. D , Density of Pseudoplastic Power-Law Fluid ρ , Volume flow rate of pseudoplastic power-law fluid flowing through a control valve Q , shear rate of pseudoplastic power-law fluid , and the apparent viscosity corresponding to the shear rate of the pseudoplastic power law fluid η .

3. A method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve according to claim 2, characterized in that: The constitutive equation of pseudoplastic power-law fluid is specifically expressed as follows: ； In the formula, represents the apparent viscosity of the pseudoplastic power-law fluid, in Pa·s; Represents the viscosity coefficient of pseudoplastic power law fluid, in Pa·s n ; n represents the flow index of pseudoplastic power-law fluid, dimensionless; represents the shear rate of pseudoplastic power-law fluid, in s -1 ;in, n and k are the constitutive constants of pseudoplastic power-law fluids.

4. A method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve according to claim 3, characterized in that: The Reynolds number of the control valve is calculated by the Reynolds number calculation equation, which is specifically expressed as follows: ； In the formula, ρ It represents the density of pseudoplastic power-law fluid in kg / m 3 ; V It represents the average flow velocity of pseudoplastic power law fluid flowing through the control valve, in m / s; Q It represents the volume flow rate of pseudoplastic power law fluid flowing through the control valve, in m 3 / s.

5. A method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve according to claim 4, characterized in that: The pressure drop when the pseudoplastic power-law fluid flows through the control valve is calculated by the pressure drop calculation equation. The pressure drop calculation equation is specifically expressed as follows: ； In the formula, It represents the pressure drop when a pseudoplastic power-law fluid flows through a control valve, in Pa.

6. A method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve according to claim 5, characterized in that: The flow coefficient calculation equation is used to calculate the flow coefficient of the control valve when the pseudoplastic power law fluid flows through the control valve. The flow coefficient calculation equation is specifically expressed as follows: ； In the formula, C V Expresses the flow coefficient of a pseudoplastic power law fluid through a control valve in gallons per minute.

7. A method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve according to any one of claims 3 to 6, characterized in that: Flow Index n The value range is (0,1).

8. A method for calculating the flow coefficient of a pseudoplastic power-law fluid control valve according to any one of claims 3 to 6, characterized in that: Reynolds number correction factor F R The value range is (0,1).

Images