A method, device, equipment and medium for measuring coefficient of deformed droplet

Abstract

The present application discloses a coefficient measurement method, device, equipment and medium for deformed droplets, which relates to the field of droplet measurement, including: inputting the current velocity vector and the current gas-liquid phase function of the fluid in the freezing wind tunnel into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid; determining the apparent thermal diffusion coefficient based on the updated current gas-liquid phase function, and updating the current temperature of the fluid in combination with the updated current velocity vector; in a cubic calculation domain predetermined based on the freezing wind tunnel, measuring the current drag coefficient of the deformed droplets in the freezing wind tunnel according to the updated current velocity vector, and measuring the current heat transfer coefficient of the deformed droplets according to the updated current temperature to determine the current cooling state of the deformed droplets. The present application more accurately estimates the cooling process of the deformed droplets by independently developing non-contact measurement of the drag coefficient and heat transfer coefficient of the deformed droplets.

Description

Technical Field

[0001] The present invention relates to the field of droplet measurement, and in particular to a method, device, equipment and medium for measuring coefficients of a deformed droplet. Background Art

[0002] The formation of cloud droplet groups needs to be simulated in the freezing wind tunnel. The basic process is: first, a group of droplets at room temperature is generated in the freezing wind tunnel, and then the droplet group is accelerated through the wind tunnel so that the temperature drops during the acceleration process to reach the supercooled state of the upper atmosphere, thereby generating supercooled clouds in the freezing wind tunnel. In fact, droplets will deform during movement, and the deformation will cause changes in the droplet internal flow and wake flow, thereby further changing the droplet's drag coefficient and heat transfer coefficient. Since the cooling process of deformed droplets in the freezing wind tunnel is an important part of the generation of supercooled clouds in the freezing wind tunnel, and the current prediction of supercooled droplets mostly relies on semi-empirical calculations that the droplets are spheres, the accuracy needs to be improved. Therefore, how to independently develop and accurately estimate the cooling process of deformed droplets is a problem that needs to be solved. Summary of the invention

[0003] In view of this, the purpose of the present invention is to provide a coefficient measurement method, device, equipment and medium for deformed droplets, which can independently develop non-contact measurement of the drag coefficient and heat transfer coefficient of deformed droplets, so as to more accurately estimate the cooling process of deformed droplets. The specific scheme is as follows:

[0004] In a first aspect, the present application provides a method for measuring coefficients of a deformed droplet, comprising:

[0005] Inputting the current velocity vector and the current gas-liquid phase function of the fluid in the icing wind tunnel into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid;

[0006] Determining a corresponding apparent thermal diffusion coefficient based on the updated current gas-liquid phase function, and updating a current temperature of the fluid using the apparent thermal diffusion coefficient and the updated current velocity vector;

[0007] In a cube calculation domain predetermined based on the freezing wind tunnel, a current drag coefficient of the deformed droplets in the freezing wind tunnel is measured according to an updated current velocity vector, and a current heat transfer coefficient of the deformed droplets in the freezing wind tunnel is measured according to an updated current temperature, so as to determine a current cooling state of the deformed droplets in the freezing wind tunnel based on the current drag coefficient and the current heat transfer coefficient.

[0008] Optionally, determining the corresponding apparent thermal diffusion coefficient based on the updated current gas-liquid phase function includes:

[0009] Determine the apparent heat capacity of the fluid according to the heat capacity of the liquid and the gas and the updated current gas-liquid phase function, and determine the apparent thermal conductivity of the fluid according to the thermal conductivity of the liquid and the gas and the updated current gas-liquid phase function;

[0010] Determine a corresponding apparent thermal diffusion coefficient based on the apparent density of the fluid, the apparent heat capacity and the apparent thermal conductivity; the apparent density is a density determined according to the densities of the liquid and the gas and the updated current gas-liquid phase function;

[0011] Wherein, the formula for determining the apparent thermal diffusion coefficient is: ; is the apparent thermal diffusion coefficient, represents the apparent thermal conductivity, represents the apparent heat capacity, Represents apparent density.

[0012] Optionally, updating the current temperature of the fluid by using the apparent thermal diffusion coefficient and the updated current velocity vector includes:

[0013] updating the current temperature of the fluid using the current displacement vector of the fluid, the apparent thermal diffusion coefficient and the updated current velocity vector;

[0014] The temperature update formula is: ; T represents temperature, t represents time, represents the displacement vector, represents the velocity vector, represents the apparent thermal diffusion coefficient; and the updated formula for temperature uses the Einstein summation convention, Indicates three different directions.

[0015] Optionally, measuring the current drag coefficient of the deformed droplet in the icing wind tunnel according to the updated current velocity vector includes:

[0016] The current drag coefficient of the deformed droplet in the icing wind tunnel is measured using far front flow parameters and characteristic area and based on the updated current velocity vector; the far front flow parameters include far front flow density and far front flow velocity, and the characteristic area is the area of ​​a cross section perpendicular to the flow direction in the cubic calculation domain;

[0017] The measurement formula of the drag coefficient is:

[0018] ;

[0019] represents the drag coefficient, represents the far front incoming flow density, represents the velocity of the far front flow, S represents the characteristic area and , and represents the length and width of the cross section perpendicular to the incoming flow direction in the cubic computational domain, Represents the velocity vectors in three different directions corresponding to the cubic computational domain.

[0020] Optionally, measuring the current heat transfer coefficient of the deformed droplets in the icing wind tunnel according to the updated current temperature includes:

[0021] The current heat transfer coefficient of the deformed droplets in the freezing wind tunnel is measured according to the maximum diameter length of the deformed droplets, the temperature change, the updated current temperature, the updated current velocity vector and the updated current gas-liquid phase function; the temperature change is the change determined based on the temperature at the front and rear positions of the droplet group after the fluid blows through the droplet group in the freezing wind tunnel;

[0022] Among them, the measurement formula of heat transfer coefficient is:

[0023] ;

[0024] represents the heat transfer coefficient, represents the maximum diameter of the deformed droplet, represents the temperature change, represents the gas-liquid phase function, represents the apparent density, represents the apparent heat capacity, T represents the temperature, represents the velocity vector, represents the displacement vector, represents the apparent thermal conductivity, represents the length, height and width of the cubic calculation domain; and the measurement formula of the heat transfer coefficient adopts the Einstein summation convention, Indicates three different directions.

[0025] Optionally, the step of inputting the current velocity vector and the current gas-liquid phase function of the fluid in the icing wind tunnel into a coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid comprises:

[0026] Inputting the current velocity vector, the current gas-liquid phase function and the current displacement vector of the fluid in the icing wind tunnel into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function, so as to determine the current vortex vector based on the current velocity vector, the current displacement vector and the curl operator, and updating the current vortex vector using the apparent kinematic viscosity and the surface tension vector of the fluid;

[0027] Determine a stream function vector based on a current displacement vector and an updated current vortex vector, and determine a velocity potential function based on the current displacement vector and the current velocity vector, update the current velocity vector using the stream function vector and the velocity potential function, and update the current gas-liquid phase function using the current displacement vector and the updated current velocity vector;

[0028] Among them, the apparent kinematic viscosity is the kinematic viscosity determined according to the apparent dynamic viscosity and apparent density of the fluid, the apparent dynamic viscosity is the dynamic viscosity determined according to the dynamic viscosity of the liquid and gas and the current gas-liquid phase function, and the apparent density is the density determined according to the density of the liquid and gas and the current gas-liquid phase function; the surface tension vector is a vector determined according to the surface tension coefficient, the curvature coefficient, the current displacement vector and the current gas-liquid phase function, the curvature coefficient is a coefficient determined according to the gas-liquid interface normal vector and the current displacement vector, and the gas-liquid interface normal vector is a vector determined according to the current displacement vector and the current gas-liquid phase function.

[0029] Optionally, the coupling relationship includes:

[0030] ;

[0031] ;

[0032] ;

[0033] ;

[0034] ;

[0035] Wherein, the coupling relation adopts the Einstein summation convention, and Indicates three different directions. Indicates three different directions. Indicates three different directions. are vortex vectors, represents the curl operator, are velocity vectors, All represent displacement vectors, t represents time, represents the apparent kinematic viscosity, represents the surface tension vector, denotes the stream function vector, represents the velocity potential function, represents the gas-liquid phase function.

[0036] In a second aspect, the present application provides a coefficient measurement device for a deformed droplet, comprising:

[0037] A first updating module is used to input the current velocity vector and the current gas-liquid phase function of the fluid in the icing wind tunnel into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid;

[0038] a second updating module, configured to determine a corresponding apparent thermal diffusion coefficient based on the updated current gas-liquid phase function, and to update a current temperature of the fluid using the apparent thermal diffusion coefficient and the updated current velocity vector;

[0039] A coefficient measurement module is used to measure the current drag coefficient of the deformed droplets in the icing wind tunnel according to the updated current velocity vector in a cubic calculation domain predetermined based on the icing wind tunnel, and to measure the current heat transfer coefficient of the deformed droplets in the icing wind tunnel according to the updated current temperature, so as to determine the current cooling state of the deformed droplets in the icing wind tunnel based on the current drag coefficient and the current heat transfer coefficient.

[0040] In a third aspect, the present application provides an electronic device, including:

[0041] Memory, used to store computer programs;

[0042] A processor is used to execute the computer program to implement the above-mentioned coefficient measurement method of deformed droplet.

[0043] In a fourth aspect, the present application provides a computer-readable storage medium for storing a computer program, wherein the computer program, when executed by a processor, implements the aforementioned method for measuring coefficients of a deformed droplet.

[0044] In the present application, the current velocity vector and the current gas-liquid phase function of the fluid in the freezing wind tunnel are input into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid; the corresponding apparent thermal diffusion coefficient is determined based on the updated current gas-liquid phase function, and the current temperature of the fluid is updated using the apparent thermal diffusion coefficient and the updated current velocity vector; in a cube calculation domain predetermined based on the freezing wind tunnel, the current drag coefficient of the deformed droplets in the freezing wind tunnel is measured according to the updated current velocity vector, and the current heat transfer coefficient of the deformed droplets in the freezing wind tunnel is measured according to the updated current temperature, so as to determine the current cooling state of the deformed droplets in the freezing wind tunnel based on the current drag coefficient and the current heat transfer coefficient. It can be seen that this application not only fills the gap in the field of cooling simulation calculation of deformed droplets in icing wind tunnels through the independent research and development of non-contact measurement of the drag coefficient and heat transfer coefficient of deformed droplets, and realizes the autonomous control of independent source code software, but also improves the measurement accuracy of the drag coefficient and heat transfer coefficient of deformed droplets, thereby more accurately estimating the cooling process of deformed droplets for icing wind tunnels. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0046] Figure 1 A flow chart of a coefficient measurement method for a deformed droplet disclosed in the present application;

[0047] Figure 2 A schematic diagram of an integral region of a deformation droplet drag coefficient disclosed in the present application;

[0048] Figure 3 A schematic diagram of an integral region of a heat transfer coefficient of a deformed droplet disclosed in the present application;

[0049] Figure 4 This is a schematic structural diagram of a coefficient measurement device for a deformed droplet disclosed in the present application;

[0050] Figure 5 This is a structural diagram of an electronic device disclosed in this application. DETAILED DESCRIPTION

[0051] 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.

[0052] Since the cooling process of deformed droplets in an icing wind tunnel is an important part of generating supercooled clouds in an icing wind tunnel, and the current prediction of supercooled droplets mostly relies on semi-empirical calculations that the droplets are spherical, the accuracy needs to be improved. To this end, this application provides a coefficient measurement method for deformed droplets, which uses a self-developed non-contact measurement of the drag coefficient and heat transfer coefficient of deformed droplets to more accurately estimate the cooling process of deformed droplets.

[0053] See also Figure 1 As shown, an embodiment of the present invention discloses a method for measuring coefficients of a deformed droplet, comprising:

[0054] Step S11, inputting the current velocity vector and the current gas-liquid phase function of the fluid in the icing wind tunnel into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid.

[0055] In an embodiment of the present invention, the current velocity vector, the current gas-liquid phase function and the current displacement vector of the fluid in the icing wind tunnel are input into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function, so as to determine the current vortex vector based on the current velocity vector, the current displacement vector and the curl operator, and update the current vortex vector using the apparent kinematic viscosity and the surface tension vector of the fluid; then, the stream function vector is determined based on the current displacement vector and the updated current vortex vector, and the velocity potential function is determined based on the current displacement vector and the current velocity vector, so as to update the current velocity vector using the stream function vector and the velocity potential function, and the current gas-liquid phase function also needs to be updated using the current displacement vector and the updated current velocity vector.

[0056] Moreover, the coupling relationship between the velocity vector, vortex vector and gas-liquid phase function is as follows:

[0057] ;

[0058] ;

[0059] ;

[0060] ;

[0061] ;

[0062] The coupling relation adopts the Einstein summation convention, and Indicates three different directions. Indicates three different directions. Indicates three different directions. are vortex vectors, represents the curl operator, are velocity vectors, All represent displacement vectors, t represents time, represents the apparent kinematic viscosity, represents the surface tension vector, denotes the stream function vector, represents the velocity potential function, It should be noted that all vectors in this application are expressed in the form of Einstein indicators.

[0063] by Take the example of Einstein's summation convention:

[0064] .

[0065] In addition, this embodiment uses the Runge-Kutta third-order format (Runge-Kutta third-order format) coupled with the Crank-Nicolson second-order format (Crank-Nicholson second-order format) to numerically discretize the unsteady time term The nonlinear convection term is numerically discretized using a hybrid format of sixth-order compact differential coupling WENO5 (Weighted Essentially Non-Oscillatory) and convection splitting technology. , the dissipative term is numerically discretized using the second-order central difference scheme and vortex stretching term , using the second-order central difference format to discretize the curl term , the second-order derivative and Both use the second-order central difference format to discretize the curl term. .

[0066] More specifically, the present embodiment inputs the current velocity vector, the current gas-liquid phase function and the current displacement vector of the fluid in the icing wind tunnel into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function, so as to determine the current vortex vector based on the current velocity vector, the current displacement vector and the curl operator, and uses the apparent kinematic viscosity and surface tension vector of the fluid, the current velocity vector, the current displacement vector, the curl operator and the vortex vector at the current moment to determine the vortex vector at the next moment, so as to update the current vortex vector, that is, the updated current vortex vector is the vortex vector at the next moment. Then, the stream function vector is determined based on the current displacement vector and the updated current vortex vector, and the velocity potential function is determined based on the current displacement vector and the current velocity vector, so as to update the current velocity vector using the curl operator, the current displacement vector, the stream function vector and the velocity potential function, and then the gas-liquid phase function at the next moment is determined based on the gas-liquid phase function at the current moment using the current displacement vector and the updated current velocity vector, so as to update the current gas-liquid phase function, that is, the updated current gas-liquid phase function is the gas-liquid phase function at the next moment.

[0067] It should also be noted that for determining the current vortex vector based on the current velocity vector, the current displacement vector and the curl operator, when considering the boundary velocity of the fluid at the wall of the icing wind tunnel, the current velocity vector can be updated using the boundary velocity first, and the current velocity vector updated using the boundary velocity can be substituted into To determine the current vortex vector.

[0068] The apparent kinematic viscosity of the fluid is the kinematic viscosity determined according to the apparent dynamic viscosity and apparent density of the fluid, and the apparent dynamic viscosity is the dynamic viscosity determined according to the dynamic viscosity of the liquid and gas and the current gas-liquid phase function, and the apparent density is the density determined according to the density of the liquid and gas and the current gas-liquid phase function. The formulas involved are as follows:

[0069] ;

[0070] represents the apparent density, represents the gas-liquid phase function, represents the density of the liquid, represents the density of the gas, represents the apparent dynamic viscosity, represents the dynamic viscosity of the liquid, represents the dynamic viscosity of the gas, Indicates apparent kinematic viscosity.

[0071] The surface tension vector is a vector determined according to the surface tension coefficient, the curvature coefficient, the current displacement vector and the current gas-liquid phase function, and the curvature coefficient is a coefficient determined according to the gas-liquid interface normal vector and the current displacement vector, and the gas-liquid interface normal vector is a vector determined according to the current displacement vector and the current gas-liquid phase function. The formulas involved are as follows:

[0072] ;

[0073] ;

[0074] The above formulas all use the Einstein summation convention, and Indicates three different directions. represents the surface tension vector, represents the surface tension coefficient, represents the curvature coefficient, represents the displacement vector, represents the gas-liquid phase function, represents the normal vector of the air-liquid interface.

[0075] Step S12: determining a corresponding apparent thermal diffusion coefficient based on the updated current gas-liquid phase function, and updating the current temperature of the fluid using the apparent thermal diffusion coefficient and the updated current velocity vector.

[0076] In the embodiment of the present invention, the corresponding apparent thermal diffusion coefficient is determined based on the updated current gas-liquid phase function, and then the temperature at the next moment is determined based on the current temperature using the apparent thermal diffusion coefficient and the updated current velocity vector to update the current temperature of the fluid, that is, the updated current temperature is the temperature at the next moment.

[0077] For determining the corresponding apparent thermal diffusion coefficient based on the updated current gas-liquid phase function, the apparent heat capacity of the fluid can be first determined based on the heat capacity of the liquid and the gas and the updated current gas-liquid phase function, and the apparent thermal conductivity of the fluid can be determined based on the thermal conductivity of the liquid and the gas and the updated current gas-liquid phase function; then the corresponding apparent thermal diffusion coefficient is determined based on the apparent density, apparent heat capacity and apparent thermal conductivity of the fluid; it should be noted that the apparent density is the density determined based on the density of the liquid and the gas and the updated current gas-liquid phase function.

[0078] Among them, the formula for determining the apparent thermal diffusion coefficient is: ; is the apparent thermal diffusion coefficient, represents the apparent thermal conductivity, represents the apparent heat capacity, represents the apparent density. The formula for determining is: ; is the heat capacity of the liquid, is the heat capacity of the gas, Represents the gas-liquid phase function. Apparent thermal conductivity The formula for determining is: ; represents the thermal conductivity of the liquid, Represents the thermal conductivity of gas.

[0079] To update the current temperature of the fluid using the apparent thermal diffusion coefficient and the updated current velocity vector, the current displacement vector, the apparent thermal diffusion coefficient and the updated current velocity vector of the fluid can be used to determine the temperature at the next moment based on the current moment temperature to update the current temperature of the fluid.

[0080] The temperature update formula is: ; T represents temperature, t represents time, represents the displacement vector, represents the velocity vector, represents the apparent thermal diffusion coefficient; and the updated formula for temperature uses the Einstein summation convention, Indicates three different directions.

[0081] Step S13: In a cube calculation domain predetermined based on the freezing wind tunnel, the current drag coefficient of the deformed droplets in the freezing wind tunnel is measured according to the updated current velocity vector, and the current heat transfer coefficient of the deformed droplets in the freezing wind tunnel is measured according to the updated current temperature, so as to determine the current cooling state of the deformed droplets in the freezing wind tunnel based on the current drag coefficient and the current heat transfer coefficient.

[0082] In an embodiment of the present invention, in a cube calculation domain predetermined based on an icing wind tunnel, the law of conservation of momentum and the law of conservation of energy can be used to measure the drag coefficient and heat transfer coefficient of a deformed droplet in an icing wind tunnel, thereby determining the cooling state of the deformed droplet in the icing wind tunnel based on the drag coefficient and heat transfer coefficient of the deformed droplet. Specifically, in a cube calculation domain predetermined based on an icing wind tunnel, the current drag coefficient of the deformed droplet in the icing wind tunnel is measured based on the updated current velocity vector, and the current heat transfer coefficient of the deformed droplet in the icing wind tunnel is measured based on the updated current temperature, thereby determining the current cooling state of the deformed droplet in the icing wind tunnel based on the current drag coefficient and the current heat transfer coefficient. The cube calculation domain may be a rectangular parallelepiped calculation domain.

[0083] For measuring the current drag coefficient of the deformed droplet in the icing wind tunnel according to the updated current velocity vector, the far front flow parameters and the characteristic area can be used to measure the current drag coefficient of the deformed droplet in the icing wind tunnel based on the updated current velocity vector; and the far front flow parameters include the far front flow density and the far front flow velocity, and the characteristic area is the area of ​​the cross section perpendicular to the flow direction in the cube calculation domain.

[0084] The measurement formula of the drag coefficient is:

[0085] ;

[0086] represents the drag coefficient, represents the far front incoming flow density, represents the velocity of the far front flow, S represents the characteristic area and , and represents the length and width of the cross section perpendicular to the flow direction in the cubic computational domain. Indicates the three different directions corresponding to the cube calculation domain The velocity vector on .

[0087] by Figure 2 For example, in the cubic computational domain pre-determined based on the icing wind tunnel, the length, height, and width of the cubic computational domain can be expressed as , the three different directions corresponding to the cubic computational domain can be expressed as After the far front flow blows through the droplet group in the icing wind tunnel, the current drag coefficient of the deformed droplets in the icing wind tunnel is measured based on the updated current velocity vector using the far front flow density, far front flow velocity and characteristic area. The integral area of ​​B is represented by the shaded area The small square area in the center of the shaded area B represents the infinitesimal element.

[0088] For measuring the current heat transfer coefficient of deformed droplets in an icing wind tunnel according to the updated current temperature, the current heat transfer coefficient of the deformed droplets in the icing wind tunnel can be measured according to the maximum diameter of the deformed droplets, the temperature change, the updated current temperature, the updated current velocity vector and the updated current gas-liquid phase function; and the temperature change is a change determined based on the temperature at the front and rear positions of the droplet group after the fluid blows through the droplet group in the icing wind tunnel.

[0089] Among them, the measurement formula of heat transfer coefficient is:

[0090] ;

[0091] represents the heat transfer coefficient, represents the maximum diameter of the deformed droplet, represents the temperature change, represents the gas-liquid phase function, represents the apparent density, represents the apparent heat capacity, T represents the temperature, represents the velocity vector, represents the displacement vector, represents the length, height, and width of the cubic computational domain; and the heat transfer coefficient measurement formula uses the Einstein summation convention, Indicates three different directions.

[0092] by Figure 3 For example, in the cubic computational domain pre-determined based on the icing wind tunnel, the length, height, and width of the cubic computational domain can be expressed as , the three different directions corresponding to the cubic computational domain can be expressed as After the far front flow Flow blows through the droplet group in the icing wind tunnel, the temperature change is determined based on the temperature at the front and rear positions of the droplet group, and the current heat transfer coefficient of the deformed droplet in the icing wind tunnel is measured in combination with the maximum diameter length, apparent density, apparent heat capacity, apparent thermal conductivity, current displacement vector, updated current temperature, updated current velocity vector and updated current gas-liquid phase function of the deformed droplet. Among them, the dV stereo box gives a schematic diagram of a single deformed droplet, and the shaded part represents the gas-liquid phase function in the cubic calculation domain. part, Indicates that there is liquid in this part.

[0093] In this way, this embodiment can gradually solve the vortex vector, velocity vector, gas-liquid phase function and temperature at each moment through the above steps S11 to S13, and finally calculate the drag coefficient and heat transfer coefficient of the deformed droplets in the freezing wind tunnel at each moment, thereby determining the cooling state of the deformed droplets in the freezing wind tunnel at each moment.

[0094] In this embodiment, the current velocity vector and the current gas-liquid phase function of the fluid in the freezing wind tunnel are input into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid; the corresponding apparent thermal diffusion coefficient is determined based on the updated current gas-liquid phase function, and the current temperature of the fluid is updated using the apparent thermal diffusion coefficient and the updated current velocity vector; in a cube calculation domain predetermined based on the freezing wind tunnel, the current resistance coefficient of the deformed droplets in the freezing wind tunnel is measured according to the updated current velocity vector, and the current heat transfer coefficient of the deformed droplets in the freezing wind tunnel is measured according to the updated current temperature, so as to determine the current cooling state of the deformed droplets in the freezing wind tunnel based on the current resistance coefficient and the current heat transfer coefficient. It can be seen that this application not only fills the gap in the field of cooling simulation calculation of deformed droplets in icing wind tunnels through the independent research and development of non-contact measurement of the drag coefficient and heat transfer coefficient of deformed droplets, and realizes the autonomous control of independent source code software, but also improves the measurement accuracy of the drag coefficient and heat transfer coefficient of deformed droplets, thereby more accurately estimating the cooling process of deformed droplets for icing wind tunnels.

[0095] See also Figure 4 As shown, an embodiment of the present invention discloses a coefficient measurement device for a deformed droplet, comprising:

[0096] The first updating module 11 is used to input the current velocity vector and the current gas-liquid phase function of the fluid in the icing wind tunnel into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid;

[0097] A second updating module 12, configured to determine a corresponding apparent thermal diffusion coefficient based on the updated current gas-liquid phase function, and to update a current temperature of the fluid using the apparent thermal diffusion coefficient and the updated current velocity vector;

[0098] The coefficient measurement module 13 is used to measure the current drag coefficient of the deformed droplets in the icing wind tunnel according to the updated current velocity vector in a cube calculation domain predetermined based on the icing wind tunnel, and to measure the current heat transfer coefficient of the deformed droplets in the icing wind tunnel according to the updated current temperature, so as to determine the current cooling state of the deformed droplets in the icing wind tunnel based on the current drag coefficient and the current heat transfer coefficient.

[0099] In this embodiment, the current velocity vector and the current gas-liquid phase function of the fluid in the freezing wind tunnel are input into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid; the corresponding apparent thermal diffusion coefficient is determined based on the updated current gas-liquid phase function, and the current temperature of the fluid is updated using the apparent thermal diffusion coefficient and the updated current velocity vector; in a cube calculation domain predetermined based on the freezing wind tunnel, the current resistance coefficient of the deformed droplets in the freezing wind tunnel is measured according to the updated current velocity vector, and the current heat transfer coefficient of the deformed droplets in the freezing wind tunnel is measured according to the updated current temperature, so as to determine the current cooling state of the deformed droplets in the freezing wind tunnel based on the current resistance coefficient and the current heat transfer coefficient. It can be seen that this application not only fills the gap in the field of cooling simulation calculation of deformed droplets in icing wind tunnels through the independent research and development of non-contact measurement of the drag coefficient and heat transfer coefficient of deformed droplets, and realizes the autonomous control of independent source code software, but also improves the measurement accuracy of the drag coefficient and heat transfer coefficient of deformed droplets, thereby more accurately estimating the cooling process of deformed droplets for icing wind tunnels.

[0100] In some specific embodiments, the second updating module 12 includes:

[0101] an apparent coefficient determination unit, used to determine the apparent heat capacity of the fluid according to the heat capacity of the liquid and the gas and the updated current gas-liquid phase function, and to determine the apparent thermal conductivity of the fluid according to the thermal conductivity of the liquid and the gas and the updated current gas-liquid phase function;

[0102] a thermal diffusion coefficient determination unit, configured to determine a corresponding apparent thermal diffusion coefficient based on an apparent density of the fluid, the apparent heat capacity and the apparent thermal conductivity; the apparent density being a density determined according to the densities of the liquid and the gas and an updated current gas-liquid phase function;

[0103] Wherein, the formula for determining the apparent thermal diffusion coefficient is: ; is the apparent thermal diffusion coefficient, represents the apparent thermal conductivity, represents the apparent heat capacity, Represents apparent density.

[0104] In some specific embodiments, the second updating module 12 includes:

[0105] a temperature updating unit, configured to update a current temperature of the fluid using a current displacement vector of the fluid, the apparent thermal diffusion coefficient, and an updated current velocity vector;

[0106] The temperature update formula is: ; T represents temperature, t represents time, represents the displacement vector, represents the velocity vector, represents the apparent thermal diffusion coefficient; and the updated formula for temperature uses the Einstein summation convention, Indicates three different directions.

[0107] In some specific embodiments, the coefficient measurement module 13 includes:

[0108] A drag coefficient measuring unit, used for measuring the current drag coefficient of the deformed droplet in the icing wind tunnel by using far front flow parameters and characteristic area and based on the updated current velocity vector; the far front flow parameters include far front flow density and far front flow velocity, and the characteristic area is the area of ​​a cross section perpendicular to the flow direction in the cubic calculation domain;

[0109] The measurement formula of the drag coefficient is:

[0110] ;

[0111] represents the drag coefficient, represents the far front incoming flow density, represents the velocity of the far front flow, S represents the characteristic area and , and represents the length and width of the cross section perpendicular to the incoming flow direction in the cubic computational domain, Represents the velocity vectors in three different directions corresponding to the cubic computational domain.

[0112] In some specific embodiments, the coefficient measurement module 13 includes:

[0113] A heat transfer coefficient measuring unit, used to measure the current heat transfer coefficient of the deformed droplets in the freezing wind tunnel according to the maximum diameter length of the deformed droplets, the temperature change, the updated current temperature, the updated current velocity vector and the updated current gas-liquid phase function; the temperature change is the change determined based on the temperature at the front and rear positions of the droplet group after the fluid blows through the droplet group in the freezing wind tunnel;

[0114] Among them, the measurement formula of heat transfer coefficient is:

[0115] ;

[0116] represents the heat transfer coefficient, represents the maximum diameter of the deformed droplet, represents the temperature change, represents the gas-liquid phase function, represents the apparent density, represents the apparent heat capacity, T represents the temperature, represents the velocity vector, represents the displacement vector, represents the apparent thermal conductivity, represents the length, height and width of the cubic calculation domain; and the measurement formula of the heat transfer coefficient adopts the Einstein summation convention, Indicates three different directions.

[0117] In some specific embodiments, the first updating module 11 includes:

[0118] a first vector updating unit, for inputting a current velocity vector, a current gas-liquid phase function and a current displacement vector of the fluid in the icing wind tunnel into a coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function, so as to determine a current vortex vector based on the current velocity vector, the current displacement vector and the curl operator, and to update the current vortex vector using the apparent kinematic viscosity and the surface tension vector of the fluid;

[0119] a second vector updating unit, configured to determine a stream function vector based on a current displacement vector and an updated current vortex vector, and to determine a velocity potential function based on the current displacement vector and a current velocity vector, to update a current velocity vector using the stream function vector and the velocity potential function, and to update a current gas-liquid phase function using the current displacement vector and the updated current velocity vector;

[0120] Among them, the apparent kinematic viscosity is the kinematic viscosity determined according to the apparent dynamic viscosity and apparent density of the fluid, the apparent dynamic viscosity is the dynamic viscosity determined according to the dynamic viscosity of the liquid and gas and the current gas-liquid phase function, and the apparent density is the density determined according to the density of the liquid and gas and the current gas-liquid phase function; the surface tension vector is a vector determined according to the surface tension coefficient, the curvature coefficient, the current displacement vector and the current gas-liquid phase function, the curvature coefficient is a coefficient determined according to the gas-liquid interface normal vector and the current displacement vector, and the gas-liquid interface normal vector is a vector determined according to the current displacement vector and the current gas-liquid phase function.

[0121] Furthermore, the present application also discloses an electronic device. Figure 5 This is a structural diagram of an electronic device 20 according to an exemplary embodiment. The content in the diagram cannot be regarded as any limitation on the scope of use of the present application.

[0122] Figure 5The present invention provides a schematic diagram of the structure of an electronic device 20 provided in an embodiment of the present application. The electronic device 20 may specifically include: at least one processor 21, at least one memory 22, a power supply 23, a communication interface 24, an input / output interface 25, and a communication bus 26. The memory 22 is used to store a computer program, which is loaded and executed by the processor 21 to implement the relevant steps in the coefficient measurement method of a deformed droplet disclosed in any of the aforementioned embodiments. In addition, the electronic device 20 in this embodiment may specifically be an electronic computer.

[0123] In this embodiment, the power supply 23 is used to provide working voltage for each hardware device on the electronic device 20; the communication interface 24 can create a data transmission channel between the electronic device 20 and the external device, and the communication protocol it follows is any communication protocol that can be applied to the technical solution of the present application, and is not specifically limited here; the input and output interface 25 is used to obtain external input data or output data to the outside world, and its specific interface type can be selected according to specific application needs and is not specifically limited here.

[0124] In addition, the memory 22, as a carrier for storing resources, can be a read-only memory, a random access memory, a disk or an optical disk, etc. The resources stored thereon can include an operating system 221, a computer program 222, etc., and the storage method can be temporary storage or permanent storage.

[0125] The operating system 221 is used to manage and control the hardware devices and computer program 222 on the electronic device 20, and can be Windows Server, Netware, Unix, Linux, etc. In addition to including a computer program that can be used to complete the coefficient measurement method of the deformed droplet performed by the electronic device 20 disclosed in any of the aforementioned embodiments, the computer program 222 can further include a computer program that can be used to complete other specific tasks.

[0126] Furthermore, the present application also discloses a computer-readable storage medium for storing a computer program; wherein, when the computer program is executed by a processor, the coefficient measurement method of a deformed droplet disclosed above is implemented. For the specific steps of the method, reference may be made to the corresponding contents disclosed in the above embodiments, and no further description will be given here.

[0127] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0128] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0129] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0130] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0131] The technical solution provided by the present application is introduced in detail above. Specific examples are used in this article to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method of the present application and its core idea. At the same time, for general technicians in this field, according to the idea of ​​the present application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A method for measuring coefficients of a deformed droplet, characterized in that: include: Inputting the current velocity vector and the current gas-liquid phase function of the fluid in the icing wind tunnel into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid; Determining a corresponding apparent thermal diffusion coefficient based on the updated current gas-liquid phase function, and updating a current temperature of the fluid using the apparent thermal diffusion coefficient and the updated current velocity vector; In a cubic calculation domain predetermined based on the icing wind tunnel, measuring a current drag coefficient of a deformed droplet in the icing wind tunnel according to an updated current velocity vector, and measuring a current heat transfer coefficient of the deformed droplet in the icing wind tunnel according to an updated current temperature, so as to determine a current cooling state of the deformed droplet in the icing wind tunnel based on the current drag coefficient and the current heat transfer coefficient; The step of inputting the current velocity vector and the current gas-liquid phase function of the fluid in the icing wind tunnel into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid comprises: Inputting the current velocity vector, the current gas-liquid phase function and the current displacement vector of the fluid in the icing wind tunnel into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function, so as to determine the current vortex vector based on the current velocity vector, the current displacement vector and the curl operator, and updating the current vortex vector using the apparent kinematic viscosity and the surface tension vector of the fluid; Determine a stream function vector based on a current displacement vector and an updated current vortex vector, and determine a velocity potential function based on the current displacement vector and the current velocity vector, update the current velocity vector using the stream function vector and the velocity potential function, and update the current gas-liquid phase function using the current displacement vector and the updated current velocity vector; Wherein, the apparent kinematic viscosity is the kinematic viscosity determined according to the apparent dynamic viscosity and the apparent density of the fluid, the apparent dynamic viscosity is the dynamic viscosity determined according to the dynamic viscosity of the liquid and the gas and the current gas-liquid phase function, and the apparent density is the density determined according to the density of the liquid and the gas and the current gas-liquid phase function; the surface tension vector is a vector determined according to the surface tension coefficient, the curvature coefficient, the current displacement vector and the current gas-liquid phase function, the curvature coefficient is a coefficient determined according to the gas-liquid interface normal vector and the current displacement vector, and the gas-liquid interface normal vector is a vector determined according to the current displacement vector and the current gas-liquid phase function; The coupling relationship includes: The coupling relation adopts the Einstein summation convention, and i=1, 2, 3 represents three different directions, j=1, 2, 3 represents three different directions, k=1, 2, 3 represents three different directions, Ω i ,Ω j Both represent the vortex vector, ε ijk represents the curl operator, u i ,u j ,u k Both represent velocity vectors, x i , x j All represent displacement vectors, t represents time, v * Represents the apparent kinematic viscosity, F k represents the surface tension vector, ψ i , ψ k All represent stream function vectors, Φ represents velocity potential function, and φ represents gas-liquid phase function; Wherein, updating the current temperature of the fluid by using the apparent thermal diffusion coefficient and the updated current velocity vector comprises: updating the current temperature of the fluid using the current displacement vector of the fluid, the apparent thermal diffusion coefficient and the updated current velocity vector; The temperature update formula is: T represents temperature, t represents time, x j represents the displacement vector, u j represents the velocity vector, α * represents the apparent thermal diffusion coefficient; and the temperature update formula adopts the Einstein summation convention, j = 1, 2, 3 represents three different directions; Wherein, measuring the current heat transfer coefficient of the deformed droplets in the icing wind tunnel according to the updated current temperature includes: The current heat transfer coefficient of the deformed droplets in the freezing wind tunnel is measured according to the maximum diameter length of the deformed droplets, the temperature change, the updated current temperature, the updated current velocity vector and the updated current gas-liquid phase function; the temperature change is the change determined based on the temperature at the front and rear positions of the droplet group after the fluid blows through the droplet group in the freezing wind tunnel.

2. The method for measuring coefficients of a deformed droplet according to claim 1, characterized in that: The determining of the corresponding apparent thermal diffusion coefficient based on the updated current gas-liquid phase function comprises: Determine the apparent heat capacity of the fluid according to the heat capacity of the liquid and the gas and the updated current gas-liquid phase function, and determine the apparent thermal conductivity of the fluid according to the thermal conductivity of the liquid and the gas and the updated current gas-liquid phase function; Determine a corresponding apparent thermal diffusion coefficient based on the apparent density of the fluid, the apparent heat capacity and the apparent thermal conductivity; the apparent density is a density determined according to the densities of the liquid and the gas and the updated current gas-liquid phase function; Wherein, the formula for determining the apparent thermal diffusion coefficient is: α * represents the apparent thermal diffusion coefficient, λ * represents the apparent thermal conductivity, C p represents the apparent heat capacity, and ρ represents the apparent density.

3. The method for measuring coefficients of a deformed droplet according to claim 1, characterized in that: The step of measuring the current drag coefficient of the deformed droplet in the icing wind tunnel according to the updated current velocity vector comprises: The current drag coefficient of the deformed droplet in the icing wind tunnel is measured using far front flow parameters and characteristic area and based on the updated current velocity vector; the far front flow parameters include far front flow density and far front flow velocity, and the characteristic area is the area of ​​a cross section perpendicular to the flow direction in the cubic calculation domain; The measurement formula of the drag coefficient is: C D represents the drag coefficient, ρ ∞ represents the far front flow density, U ∞ represents the velocity of the far front flow, S represents the characteristic area and S = L y ·L z , L y and L z represents the length and width of the cross section perpendicular to the incoming flow direction in the cubic calculation domain, and u1, u2, and u3 represent velocity vectors in three different directions corresponding to the cubic calculation domain.

4. The method for measuring coefficients of a deformed droplet according to claim 1, characterized in that: The measurement formula of heat transfer coefficient is: Nu represents the heat transfer coefficient, d p represents the maximum diameter of the deformed droplet, ΔT represents the temperature change, φ represents the gas-liquid phase function, ρ represents the apparent density, C p represents the apparent heat capacity, T represents the temperature, u j represents the velocity vector, x j represents the displacement vector, λ * represents the apparent thermal conductivity, L x , L y , L z represents the length, height and width of the cubic calculation domain; and the measurement formula of the heat transfer coefficient adopts the Einstein summation convention, and j=1, 2, 3 represents three different directions.

5. A coefficient measuring device for a deformed droplet, characterized in that: The coefficient measuring device of the deformed droplet is used to implement the coefficient measuring method of the deformed droplet according to any one of claims 1 to 4, and the coefficient measuring device of the deformed droplet comprises: A first updating module is used to input the current velocity vector and the current gas-liquid phase function of the fluid in the icing wind tunnel into the coupling relationship between the velocity vector, the vortex vector and the gas-liquid phase function to update the current vortex vector, the current velocity vector and the current gas-liquid phase function of the fluid; a second updating module, configured to determine a corresponding apparent thermal diffusion coefficient based on the updated current gas-liquid phase function, and to update a current temperature of the fluid using the apparent thermal diffusion coefficient and the updated current velocity vector; A coefficient measurement module is used to measure the current drag coefficient of the deformed droplets in the icing wind tunnel according to the updated current velocity vector in a cubic calculation domain predetermined based on the icing wind tunnel, and to measure the current heat transfer coefficient of the deformed droplets in the icing wind tunnel according to the updated current temperature, so as to determine the current cooling state of the deformed droplets in the icing wind tunnel based on the current drag coefficient and the current heat transfer coefficient.

6. An electronic device, characterized in that: include: Memory, used to store computer programs; A processor, configured to execute the computer program to implement the coefficient measurement method for a deformed droplet according to any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that: Used to store a computer program, which, when executed by a processor, implements the coefficient measurement method for a deformed droplet as claimed in any one of claims 1 to 4.

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