JP5749079B2 - Two-phase heat flow analysis apparatus and two-phase heat flow analysis method - Google Patents

Description

  The present invention relates to a two-phase heat flow analysis apparatus and a two-phase heat flow analysis method for predicting a heat flow phenomenon of a two-phase flow accompanied by a phase change phenomenon such as boiling.

  The boiling phenomenon is used in nuclear power plants and thermal boilers, and analysis is effective for evaluating and elucidating this phenomenon. When boiling occurs, water vapor is generated, and the fluid becomes a two-phase flow in which a liquid and a gas are mixed. Therefore, in order to evaluate the thermal flow phenomenon, it is necessary to apply a two-phase flow analysis method.

  In the conventional two-phase flow analysis, in order to evaluate the interaction between the gas phase and the liquid phase, a constitutive equation obtained empirically from tests or the like is often used. This constitutive equation is given differently for each flow mode such as bubble flow, slag flow, churn flow, and annular spray flow classified according to the proportion of the gas phase in the fluid.

  The constitutive equation to be applied to the two-phase flow field to be analyzed can be switched by discriminating the flow mode of the two-phase flow using a flow mode map created empirically from tests or the like. An example of such a technique is described in, for example, Non-Patent Document 1 described later (see Non-Patent Document 1).

  In recent years, a method for analyzing a two-phase flow has been established without using a constitutive equation and a flow pattern map, although it is applied to the behavior of a virtual fluid. An example of such a technique is, for example, a two-phase flow analysis method using a phase field method, which is described in Non-Patent Document 2 and the like described later (see Non-Patent Document 2).

  FIG. 6 is a diagram for explaining the concept of the phase field method, and is an explanatory diagram showing the density distribution of the inside and outside of the boiling bubble and the interface.

  In the phase field method, as shown in FIG. 6, the interface between the gas phase and the liquid phase has a certain finite thickness, and physical properties such as density and viscosity continuously change at the interface. Numerical analysis is performed assuming that In other words, an arbitrary width (thickness) is set at the interface between the gas phase and the liquid phase, and numerical analysis is performed assuming that physical property values such as density and viscosity change continuously within the set width. Do. The phase field method can efficiently handle complex phenomena that undergo large deformation while undergoing phase change at the interface, enabling direct evaluation of phase change phenomena such as boiling.

Supervised by Mamoru Akiyama and Masanori Arisu, “New numerical analysis of gas-liquid two-phase flow -multidimensional flow analysis-”, Corona, January 10, 2002, Chapter 2 Naoki Takada and Akio Hatakeyama, “Numerical simulation of two-phase flow with phase change using phase field method”, Progress in multiphase flow research, Volume 2, 2007, p. 173-180

  However, in the technique described in Non-Patent Document 1, when the gas-liquid two-phase flow accompanied by the transition of the flow mode is handled, the above-described constitutive equation and the flow mode map are created empirically from the test or the like. There is a problem that depends on the quality of the map.

  On the other hand, the technique described in Non-Patent Document 2 does not depend on the above-described constitutive equation and flow pattern map, but at present, the behavior of a virtual fluid such as a van der Waals fluid that assumes the vicinity of the critical point of the fluid is assumed. There are only analysis application examples. That is, there is no analysis application example with an actual fluid that is not virtual, and for example, there has been a problem that the thermal flow of fluid in an actual machine such as a heat exchanger in a nuclear power plant has not been established as an analysis technique.

  The present invention has been made to solve the above-described problems, and does not depend on the constitutive equation and the flow mode map, and directly evaluates the heat flow phenomenon of the two-phase flow under the conditions for the actual machine. An object of the present invention is to provide a two-phase heat flow analysis apparatus and a two-phase heat flow analysis method.

In order to solve the above-described problem, the two-phase heat flow analysis apparatus according to the present invention is configured to analyze the shape data of an analysis target given from an input unit and a heat source from which heat enters and exits a plurality of sections obtained by dividing a flow field. Based on initial parameters including initial range of region, boundary condition between this heat source region and other region, flow velocity, pressure, enthalpy, and physical properties including density, viscosity and thermal conductivity. A fluid calculation unit that calculates the flow velocity, pressure, and enthalpy of the two-phase flow, and a data storage area for the plurality of sections based on the pressure and enthalpy of the two-phase flow calculated by the fluid calculation unit. The mass flow rate calculation unit for calculating the mass flow rate fraction of the two-phase flow with reference to the stored mathematical formula information for calculating the mass flow rate fraction of the two-phase flow and the information of the state equation, and the plurality of sections Against the data While referring to the information of the state equation stored in the storage area, the physical property values including the density, viscosity and thermal conductivity of each phase constituting the two-phase flow are obtained, while the physical properties of the two-phase flow stored in the data storage area are obtained. Referring to the mathematical formula information for calculating the value, based on the physical property value of each phase constituting the two-phase flow and the mass flow rate fraction of the two-phase flow calculated by the mass flow rate calculation unit, the two-phase flow Based on the physical property value calculation unit for calculating physical property values including density, viscosity and thermal conductivity, the flow velocity, pressure and enthalpy of the two-phase flow calculated by the fluid calculation unit, and preset calculation end conditions, A calculation end determination unit that determines whether or not the calculation end condition is satisfied, a first region that is located within a predetermined range from the heat source region, and a position outside the predetermined range are all the analysis target regions. The fluid calculation unit The mass flow rate fraction calculation unit and the physical property value calculation unit are configured to calculate at least one physical property value of the density, viscosity, and thermal conductivity of the two-phase flow in the first region, A macro fluid calculation unit for calculating the flow velocity, pressure, enthalpy and void fraction of the two-phase flow in the region of 2, and the flow velocity, pressure and enthalpy of the two-phase flow in the first region calculated by the fluid calculation unit; , The physical property value calculating unit calculates at least one physical property value of the density, viscosity and thermal conductivity of the two-phase flow in the first region, and the density of the two-phase flow stored in the data storage region, The two-phase in the first region calculated by the physical property value calculation unit based on information defining a relationship between at least one physical property value of viscosity and thermal conductivity and a void ratio of the two-phase flow A first conversion processing unit that converts at least one physical property value of flow density, viscosity, and thermal conductivity into a void fraction of the two-phase flow and gives the macro fluid calculation unit, and stored in a data storage area The two-phase flow calculated by the macro fluid calculation unit with reference to information defining the relationship between the physical property value of at least one of the density, viscosity and thermal conductivity of the two-phase flow and the void ratio of the two-phase flow A second conversion processing unit that converts the void fraction of the flow into at least one physical property value of the density, viscosity, and thermal conductivity of the two-phase flow and applies the converted value to the fluid calculation unit. To do.

A two-phase heat flow analysis method according to the present invention is a method for predicting a heat flow phenomenon of a two-phase flow using a computer in order to solve the above-described problem, and the fluid calculation unit has a plurality of divided flow fields. For the section, the shape data of the analysis target given from the input unit, the range of the heat source region where heat enters and exits, the boundary condition between this heat source region and other regions, the flow velocity of the two-phase flow to be analyzed, the pressure, A fluid calculation step for calculating the flow velocity, pressure and enthalpy of the two-phase flow based on enthalpy and initial parameters including initial values of physical properties including density, viscosity and thermal conductivity, and a mass flow rate calculation unit, for a plurality of compartments, based on the pressure and enthalpy of two-phase flow calculated in the fluid calculation step, the formula information for calculating the mass flow rate fraction of the two-phase flow has been stored in the data storage area, state how The mass flow rate calculation step of calculating the mass flow rate fraction of the two-phase flow with reference to the information of the equation, and the physical property value calculation unit of the state equation stored in the data storage area for the plurality of sections While referring to the information, obtain physical property values including the density, viscosity and thermal conductivity of each phase constituting the two-phase flow, while referring to mathematical formula information for calculating the physical property values of the two-phase flow stored in the data storage area And, based on the physical property value of each phase constituting the two-phase flow and the mass flow rate fraction of the two-phase flow calculated in the mass flow rate calculation step, the density, viscosity, and thermal conductivity of the two-phase flow A physical property value calculating step for calculating a physical property value including: a first region located within a predetermined range from the heat source region, and a first region located outside the predetermined range. Divided into two regions, the fluid calculation unit, the mass flow rate While the calculation unit and the physical property value calculation unit are configured to calculate at least one physical property value of the density, viscosity, and thermal conductivity of the two-phase flow in the first region, the macro fluid calculation unit Is a macro fluid calculation step for calculating the flow velocity, pressure, enthalpy and void fraction of the two-phase flow in the second region, and the first conversion processing unit calculates the first region for the fluid calculation unit to calculate. The flow velocity, pressure and enthalpy of the two-phase flow in the above, and at least one physical property value of the density, viscosity and thermal conductivity of the two-phase flow in the first region calculated by the physical property value calculation unit, data Based on the information defining the relationship between at least one physical property value of the density, viscosity and thermal conductivity of the two-phase flow stored in the storage area and the void ratio of the two-phase flow, the physical property meter A physical property value of at least one of the density, viscosity and thermal conductivity of the two-phase flow in the first region calculated by the calculation unit is converted into the void fraction of the two-phase flow and given to the macro fluid calculation unit The first conversion processing step and the second conversion processing unit store at least one physical property value of the density, viscosity, and thermal conductivity of the two-phase flow stored in the data storage area and the void ratio of the two-phase flow. The void ratio of the two-phase flow calculated by the macro fluid calculation unit is converted into at least one physical property value of the density, viscosity, and thermal conductivity of the two-phase flow. A second conversion processing step applied to the fluid calculation unit and a calculation end determination unit, the flow velocity, pressure and enthalpy of the two-phase flow in the first region calculated in the fluid calculation step, and the macro fluid calculation. In steps Flow rate of the two-phase flow in the second region issued, pressure, and enthalpy and void fraction, based on the calculation end condition set in advance, calculates and determines whether to satisfy the calculation end condition An end determination step.

  According to the present invention, when analyzing a heat flow phenomenon of a two-phase flow accompanied by a phase change such as boiling, the phenomenon itself is directly evaluated without using a constitutive equation and a flow pattern map created from an experiment or the like. be able to.

The functional block diagram which showed roughly the functional structure of the two-phase heat-fluid-analysis apparatus which concerns on 1st Embodiment of this invention. The processing flowchart which shows the process sequence of the two-phase heat flow analysis method which concerns on 1st Embodiment of this invention. Explanatory drawing which shows the heat source area | region where the heat | fever which comes and goes in and out of the two calculation area | regions and the two-phase flow phenomenon which numerically analyze by the two-phase heat-fluid-analysis apparatus and two-phase heat-fluid-analysis method which concern on 2nd Embodiment of this invention. The functional block diagram which showed schematically the functional structure of the two-phase thermal-fluid-analysis apparatus which concerns on 2nd Embodiment of this invention. The processing flowchart which shows the process sequence of the two-phase heat flow analysis method which concerns on 2nd Embodiment of this invention. It is a figure explaining the concept of a phase field method, and explanatory drawing which shows the inside and outside of a bubbling bubble, and the density distribution of an interface.

  Hereinafter, a two-phase heat flow analysis apparatus and a two-phase heat flow analysis method according to embodiments of the present invention will be described with reference to the accompanying drawings.

[First Embodiment]
FIG. 1 is a functional block diagram schematically showing a functional configuration of a first two-phase heat flow analysis apparatus 10A that is an example of a two-phase heat flow analysis apparatus according to the first embodiment of the present invention. .

  The first two-phase heat flow analysis device 10A includes, for example, an input unit 11, a fluid calculation unit 12, a quality calculation unit 13, a physical property value calculation unit 14, and a calculation end, which are each means of the first two-phase heat flow analysis device. By causing the computer to execute a first two-phase heat flow analysis program (not shown in FIG. 1) that functions as the determination unit 15 and the display unit 16, a computer that is a hardware resource and a program that is a software resource cooperate with each other. It is a device that is realized.

  The first two-phase thermal flow analysis apparatus 10A includes a fluid calculation unit 12 that calculates the flow velocity, pressure, and enthalpy of a fluid, and a quality calculation unit that calculates a mass flow rate fraction (quality) of a fluid composed of two phases. (Mass flow rate fraction calculation unit) 13, physical property value calculation unit 14 for calculating physical property values such as density, viscosity (viscosity coefficient), thermal conductivity, specific heat, etc. A calculation end determination unit 15 for determining When the calculation end determination unit 15 determines that the calculation end condition is satisfied, the calculation result obtained in the immediately preceding time step is displayed on the display unit 16 configured by display means such as a display.

  Note that reference numeral 21 shown in FIG. 1 is quality calculation information including mathematical expression and parameter information used for calculating quality, and reference numeral 22 includes mathematical expression and parameter information used for calculating physical property values. This is physical property value calculation information. The quality calculation information 21 and the physical property value calculation information 22 are stored, for example, in a data storage area that can be read by a computer that executes the first two-phase heat flow analysis program.

  The input unit 11 is realized by, for example, an input device connected to a computer via an interface or input means such as a keyboard or a mouse provided in the computer itself. The input unit 11 gives information input to any of the fluid calculation unit 12, the quality calculation unit 13, the physical property value calculation unit 14, the calculation end determination unit 15, and the display unit 16 according to the type of input information. .

  The initial parameters given from the input unit 11 include, for example, shape data of an analysis target for a plurality of sections obtained by dividing a flow field, a range of a heat source region where heat enters and exits, a heat source region and other regions (of the analysis target other than the heat source region) Area), initial values of physical properties including the flow velocity, pressure, enthalpy, density, viscosity, and thermal conductivity of the two-phase flow to be analyzed.

  The fluid calculation unit 12 is means for performing an analysis calculation of heat flow using a known method such as a phase field method. For example, the fluid calculation unit 12 performs, for example, a finite volume method using a calculation grid or a finite difference method on a section obtained by dividing a flow field space into a plurality of sections based on initial parameters given from input means such as the input unit 11. Calculation is performed by applying a known numerical analysis method.

  The fluid calculation unit 12 has a function of determining whether the fluid in each section obtained by dividing the flow field space into a plurality of phases is in a two-phase state including an interface, and, for example, an initial value given from input means such as the input unit 11 Based on the parameters, it has the function of calculating the fluid flow rate, pressure and enthalpy. When the fluid has two phases, the fluid calculation unit 12 can calculate the flow velocity, pressure, and enthalpy of the fluid while tracking the interface between the phases. Moreover, when the fluid is a single phase, the fluid calculation unit 12 can calculate the flow velocity, pressure, and enthalpy of the fluid in the phase.

  When the fluid in each section obtained by dividing the flow field space into a plurality of phases is in a two-phase state including an interface, the quality calculation unit 13 calculates the pressure and enthalpy calculated by the fluid calculation unit 12 and quality calculation information that can be read in advance. 21 is a means for calculating a mass flow rate fraction (quality) for a section including an interface based on information possessed by 21.

  In addition, the quality calculation unit 13 uses, for example, a state equation given by a vapor table or the like provided by an organization such as the Japan Society of Mechanical Engineers and the like, and calculates a physical property value of a liquid and a gas in a saturated state, and a flow field space Is divided into a plurality of sections in a two-phase state including an interface, the interface is determined based on the pressure and enthalpy calculated by the fluid calculation unit 12 and the information included in the quality calculation information 21 that can be read in advance. It has a function of calculating the mass flow rate fraction (quality) for the included compartment, and a function of outputting the calculation result of the mass flow rate fraction to the physical property value calculation unit 14.

The quality calculation information 21 includes state equation information given by a steam table or the like, and mathematical formula information for calculating a mass flow rate fraction (quality) x. The mass flow rate fraction x is the enthalpy h of the two-phase flow in the section obtained by the fluid calculation unit 12, the pressure and enthalpy calculated by the fluid calculation unit 12, and the enthalpy h _{l of the} low temperature phase derived from the above equation of state, When the enthalpy h _{h of the} phase is calculated, it is calculated by the following equation (1) The mass flow rate x varies depending on the type of the substance that changes in phase. Therefore, when a plurality of kinds of substances are to be analyzed, they are prepared for each substance.

  The physical property value calculation unit 14 uses the pressure and enthalpy in each section calculated by the fluid calculation unit 12, the mass flow rate (quality) calculated by the quality calculation unit 13, and the information included in the physical value calculation information 22 that can be read in advance. Based on this, it is a means for calculating physical property values such as density, viscosity, thermal conductivity and specific heat of single-phase and two-phase fluids.

The physical property value calculation information 22 includes information on a state equation given by a steam table or the like, and mathematical formula information for calculating physical property values such as two-phase density, viscosity, thermal conductivity, and specific heat. The density of two-phase flow [rho, gas volume fraction (void fraction) alpha _g, liquid volume fraction alpha _l, viscosity mu, thermal conductivity lambda, the specific heat c _p, depending respectively, the following equation (2) - (10) Calculated. Note that the physical property values differ depending on the types of substances that undergo phase change. Therefore, when a plurality of types of substances are to be analyzed, they are prepared for each substance.

  For physical property values such as density, viscosity, thermal conductivity, and specific heat of a single phase (solid phase, liquid phase and gas phase), the physical property value calculation unit 14 refers to information on a state equation given by a vapor table or the like. Can be obtained.

  The calculation end determination unit 15 determines whether or not the predetermined calculation end condition is satisfied based on the calculation result of the fluid flow velocity, pressure, and enthalpy calculated by the fluid calculation unit 12 and the predetermined calculation end condition. It is a means to determine.

  The calculation end condition can be given by, for example, giving the convergence condition given by the three conservation laws of fluid mass, momentum and energy, giving parameters and values, or by the number of time steps to finish the calculation. Several methods can be employed, such as giving.

  When the calculation end determination unit 15 determines that the calculation end condition specified in advance is satisfied, the fluid flow velocity, pressure and enthalpy calculated in the current one time step, and density, viscosity, thermal conductivity, A physical property value such as specific heat is given to the display unit 16 as a calculation result. On the other hand, if it is determined that the pre-specified calculation termination conditions are not satisfied, the fluid flow velocity, pressure and enthalpy calculated in the current one time step, and physical properties such as density, viscosity, thermal conductivity, specific heat, etc. Is given to the fluid calculation unit 12.

  The display unit 16 is realized by display means such as a display device connected to a computer via an interface or a display included in the computer itself. When the display unit 16 receives a display request received by the input unit 11 or a calculation result display request from the calculation end determination unit 15, the display unit 16 displays the content corresponding to the display request on the screen.

  For example, when the display unit 16 receives a request to display the calculation result of the pressure and enthalpy in each section calculated by the fluid calculation unit 12 from the input unit 11, the display unit 16 displays each calculation calculated by the fluid calculation unit 12. The calculation result of the pressure and enthalpy in the compartment is displayed on the screen. In addition, when the display unit 16 receives a calculation result display request from the calculation end determination unit 15, physical property values (for example, flow velocity, pressure, enthalpy, density, viscosity, thermal conductivity, and Specific heat) is received from the calculation end determination unit 15 and displayed on the screen.

  As described above, the first two-phase heat flow analysis device 10A is configured to analyze the flow velocity of the fluid to be analyzed based on the initial parameters of the analysis target given from the input unit 11 to the plurality of sections obtained by dividing the flow field. The fluid calculation unit 12 that calculates pressure and enthalpy, and the two-phase flow stored in the data storage area based on the pressure and enthalpy of the two-phase flow calculated by the fluid calculation unit 12 for the plurality of sections. A mass flow rate calculation unit 13 for calculating a mass flow rate fraction of a two-phase flow with reference to quality calculation information 21 having mathematical formula information for calculating a mass flow rate fraction and state equation information, and for the plurality of sections The physical property value calculation information 22 having the mathematical formula information for calculating the physical property value of the two-phase flow stored in the data storage area and the state equation information is referred to, and the density and viscosity (viscosity) of each phase constituting the two-phase flow Coefficient) and heat transfer While obtaining the physical property value including the rate, the density and viscosity of the two-phase flow based on the physical property value of each phase constituting the two-phase flow and the mass flow rate fraction of the two-phase flow calculated by the mass flow rate calculation unit 13 Completion of the calculation based on the physical property value calculation unit 14 for calculating the physical property value including the thermal conductivity, the flow velocity, pressure and enthalpy of the two-phase flow calculated by the fluid calculation unit 14 and preset calculation end conditions A calculation end determination unit 15 for determining whether or not the condition is satisfied.

  Next, a first two-phase heat flow analysis method that is an example of the two-phase heat flow analysis method according to the first embodiment of the present invention will be described.

  FIG. 2 is an example of a first two-phase heat flow analysis method, and is a process flow diagram showing a process procedure of a first two-phase heat flow analysis procedure performed by the first two-phase heat flow analysis apparatus 10A.

  The first two-phase heat flow analysis procedure includes a fluid calculation step (step S1) in which the fluid calculation unit 12 calculates the flow velocity, pressure, and enthalpy of the fluid, and the quality calculation unit 13 determines the quality of the fluid composed of two phases. A quality calculating step (step S2) to be calculated, a physical property value calculating step (step S3) in which the physical property value calculating unit 14 calculates physical property values such as density, viscosity, thermal conductivity, specific heat, and a calculation end determining unit 15 in advance. A calculation end determination step (step S4) for determining whether or not the given calculation end condition is satisfied.

  When the first two-phase heat flow analysis procedure receives the process execution request of the first two-phase heat flow analysis procedure and the input of initial parameters necessary for the calculation after step S1, the execution of the process procedure is started (START). ). Here, the initial parameters are, for example, flow field shape data, heating (or cooling) zone boundary conditions, and fluid flow velocity, pressure, enthalpy, temperature, and physical properties such as density, viscosity, thermal conductivity, and specific heat. Value.

  In step S1, the fluid calculation unit 12 determines that the fluid in each section divided into a plurality of flow field spaces is vapor or vapor based on the initial parameters received for the sections obtained by dividing the flow field space into a plurality of sections. It is determined whether it is a single-phase state consisting of only a liquid or a two-phase state including an interface, and the flow velocity, pressure and enthalpy of the fluid are calculated (fluid calculation step).

  For example, the fluid calculation unit 12 determines whether or not there is an interface between phases based on an initial parameter that has received an input, and determines whether the fluid to be analyzed is in a single-phase state or a two-phase state. When it is determined that the two-phase state includes the interface, for example, the flow velocity, pressure, and enthalpy of the two-phase fluid are calculated based on the phase field method or the like. When the fluid flow velocity, pressure and enthalpy are calculated, the processing step of step S1 is completed.

  In the subsequent step S2, the quality calculation unit 13 refers to the fluid pressure and enthalpy calculated in step S1 and the quality calculation information 21, and calculates a mass flow rate fraction (quality) for the compartment including the interface. (Quality calculation step).

The mass flow rate fraction is calculated by the quality calculation unit 13 by substituting numerical values for the parameters h, h _l , h _h of the formula (1) using the above-described formula (1) included in the quality calculation information 21. This can be calculated. Here, as the enthalpy h of the two-phase flow included in the equation (1), the one calculated by the fluid calculation unit 12 is used. The low temperature phase enthalpy h _l and the high temperature phase enthalpy h _h use the results calculated using the equation of state included in the quality calculation information 21. When the mass flow rate fraction is calculated, the processing step of step S2 is completed.

  In subsequent step S3, the physical property value calculation unit 14 calculates the pressure and enthalpy in each section calculated in the fluid calculation step (step S1), and the calculated mass flow rate fraction (step S2) calculated in the quality calculation step (step S2). (Quality) x and two-phase based on mathematical information (Formulas (2) to (10)) for calculating physical properties such as density, viscosity, thermal conductivity, specific heat, etc. Physical property values such as density, viscosity, thermal conductivity, specific heat, etc. are calculated (physical property value calculation step).

  The physical property value calculated in step S3 is a physical property value after one time step with respect to the input in step S1. When physical property values such as two-phase density, viscosity, thermal conductivity, and specific heat are calculated, the processing step of step S3 is completed.

  In subsequent step S4, if the calculation end determination unit 15 determines whether or not a predetermined calculation end condition is satisfied, and if it is determined to be satisfied (YES in step S4), the first two-phase heat flow analysis The procedure ends (END).

  On the other hand, when the calculation end determination unit 15 determines that the calculation end condition specified in advance is not satisfied (NO in step S4), the process returns to step S1, and the processes after step S1 are repeated. That is, calculation of physical properties such as flow velocity, pressure, enthalpy, temperature, and density, viscosity, thermal conductivity, specific heat, etc. after the next one time step is started. When the processing steps after step S1 are n (n is a natural number of 2 or more) and subsequent times, the flow velocity, pressure, enthalpy, temperature, density, and viscosity of the fluid calculated at the (n-1) th time step immediately before Physical property values such as thermal conductivity and specific heat are used.

  Next, an example of the first two-phase heat flow analysis method according to heat input / output (heating or cooling) in the fluid to be analyzed and the heat source region will be described.

(1) First Example In the first example, the fluid to be analyzed is water, and the heat source region that is part of the boundary surrounding the analysis region heats the fluid (water) to be analyzed. It is an example. In the first embodiment, it is considered that the heat source region heats the fluid (water) to evaluate the phenomenon in which water boils and vapor bubbles are generated by analysis.

In the case of the first embodiment, as the quality calculation information 21, information on the state equation for calculating the physical property value of water in the saturated state is given by a steam table or the like, and the mass calculated by the quality calculation unit 13 by the equation (1). Calculate the flow rate fraction x. Moreover, as mathematical formula information for calculating the physical property value of the physical property value calculation information 22, the density ρ of the gas-liquid two-phase flow is obtained if there are equations (2) and (3), and the gas-liquid two-phase if there is equation (4). The gas volume fraction (void fraction) α _g of the flow, the viscosity μ of the gas-liquid two-phase flow if there is the equation (6), the thermal conductivity λ of the gas-liquid two-phase flow if there is the equation (8), (10) it is possible to calculate the specific heat c _p of the gas-liquid two-phase flow, if any.

  In the first embodiment, the behavior in which water boils in the heat source region (heating region) and steam is generated can be analyzed, and two-phase flow phenomena such as boiling heat transfer can be evaluated without using a constitutive equation.

(2) Second Example In the second example, the fluid to be analyzed is water vapor, and the heat source region that is a part of the boundary surrounding the analysis region cools the fluid to be analyzed (water vapor). It is an example. In the second embodiment, it is considered that the heat source region cools the fluid (water vapor) to evaluate the phenomenon of condensation and becoming liquid by analysis.

In the case of the second embodiment, as the quality calculation information 21, information on a state equation for calculating the physical property value of water vapor in a saturated state is given by a steam table or the like, and the mass calculated by the quality calculation unit 13 by the equation (1). Calculate the flow rate fraction x. Moreover, as mathematical formula information for calculating the physical property value of the physical property value calculation information 22, the density ρ of the gas-liquid two-phase flow is obtained if there are equations (2) and (3), and the gas-liquid two-phase if there is equation (4). The gas volume fraction (void fraction) α _g of the flow, the viscosity μ of the gas-liquid two-phase flow if there is the equation (6), the thermal conductivity λ of the gas-liquid two-phase flow if there is the equation (8), (10) it is possible to calculate the specific heat c _p of the gas-liquid two-phase flow, if any.

  In the second embodiment, a behavior in which water vapor is condensed in the heat source region (cooling region) and water is generated can be analyzed, and a two-phase flow phenomenon such as condensation heat transfer can be evaluated without using a constitutive equation.

(3) Third Example In the third example, the fluid to be analyzed is water or ice. That is, when the fluid to be analyzed is water and the heat source region that is a part of the boundary surrounding the analysis region is a cooling region that cools water, the phenomenon that water is cooled and solidifies to form ice. This is an example of evaluation by analysis. In addition, when the fluid to be analyzed is ice and the heat source region that is part of the boundary surrounding the analysis region is a heating region that heats ice, the phenomenon that ice melts to form water is evaluated by analysis This is an example.

In the case of the third embodiment, as the quality calculation information 21, information on a state equation for calculating the physical property value of water vapor in a saturated state is given by a steam table or the like, and the mass calculated by the quality calculation unit 13 by the equation (1). Calculate the flow rate fraction x. Further, as mathematical formula information for calculating the physical property value of the physical property value calculation information 22, if there is the formula (2), (3), the density ρ of the solid-liquid two-phase flow, and if there is the formula (5), the solid-liquid two-phase The liquid volume fraction α _l of the flow, the viscosity μ of the solid-liquid two-phase flow if there is an equation (7), the thermal conductivity λ of the solid-liquid two-phase flow if there is the equation (9), and the equation (10) it is possible to calculate the specific heat c _p of the two-phase flow, if any.

  In the third embodiment, the process of water solidifying and forming ice in the heat source region (cooling region) and the process of ice melting and forming water in the heat source region (heating region) are analyzed, and constitutive equations are not used. In addition, solid-liquid two-phase flow phenomena such as heat exchange between phases can be evaluated.

(4) Fourth Example The fourth example is an example in which a substance other than water is applied instead of water, which is the substance to be analyzed in the first to third examples. In the fourth embodiment, information on a substance to be analyzed is used as the quality calculation information 21 and the physical property value calculation information 22. Thereby, the quality calculation part 13 can calculate the physical-property value and quality in the saturation state of a fluid using the practical state equation etc. of the fluid made into analysis object. That is, in this embodiment, even when a substance other than water is used as an analysis target, the same result as in the first to third embodiments can be obtained.

  As described above, according to the first two-phase heat flow analysis device 10A and the first two-phase heat flow analysis method, the boiling heat transfer coefficient conventionally given by the constitutive equation for the fluid such as water, etc. Can be directly obtained as a calculation result without using a constitutive equation. That is, according to the first two-phase heat flow analysis device 10A and the first two-phase heat flow analysis method, the two-phase flow phenomenon such as boiling heat transfer or condensation heat transfer is directly evaluated without using a constitutive equation. Can do.

[Second Embodiment]
The two-phase heat flow analysis device and the two-phase heat flow analysis method according to the second embodiment of the present invention are more than the two-phase heat flow analysis device and the two-phase heat flow analysis method according to the first embodiment of the present invention. And an apparatus and a method for efficiently analyzing a wider area.

  FIG. 3 shows two calculation regions numerically analyzed by the two-phase heat flow analysis apparatus and the two-phase heat flow analysis method according to the second embodiment of the present invention, and a heat source region where heat that causes a two-phase flow phenomenon enters and leaves. It is explanatory drawing.

  As shown in FIG. 3, in the two-phase heat flow analysis device and the two-phase heat flow analysis method according to the second embodiment of the present invention, in a region closer than a predetermined distance from a heating wall surface 31 that is an example of a heat source region. The analysis target area is divided into two areas, a certain boiling calculation area 32 and a macro fluid calculation area 33 which is a far area, and the analysis is performed.

  In the two-phase heat flow analysis device and the two-phase heat flow analysis method according to the second embodiment of the present invention, the fluid calculation in the boiling calculation region 32 is performed using a method that can directly evaluate the phase change phenomenon using the phase field method or the like. On the other hand, the fluid calculation in the other region, that is, the macro fluid calculation region 33 is performed by applying a two-fluid model, which is an example of a conventional method described in Non-Patent Document 1, for example.

  3 is a calculation region boundary which is a boundary between the two calculation regions 32 and 33. Moreover, the heating wall surface 31 which is an example of the heat source area | region shown by FIG. 3 is an example of the heat source area | region in the case of heating a fluid, and when cooling a fluid conversely, it becomes a cooling wall surface.

  FIG. 4 is a functional block diagram schematically showing a functional configuration of a second two-phase heat flow analysis device 10B that is an example of the two-phase heat flow analysis device according to the second embodiment of the present invention. .

  As shown in FIG. 4, the second two-phase heat flow analysis device 10B is different from the first two-phase heat flow analysis device 10A in the macro fluid calculation unit 36, the first conversion processing unit 37, The second difference is that the second conversion processing unit 38 is further provided. Therefore, in the description of the present embodiment, the description will focus on differences from the above-described first embodiment, and the same components are denoted by the same reference numerals and description thereof is omitted.

  The second two-phase heat flow analysis device 10B includes, for example, an input unit 11, a fluid calculation unit 12, a quality calculation unit 13, a physical property value calculation unit 14, and a calculation end, which are each means of the second two-phase heat flow analysis device. A second two-phase heat flow analysis program (not shown in FIG. 4) that functions as the determination unit 15, the display unit 16, the macro fluid calculation unit 36, the first conversion processing unit 37, and the second conversion processing unit 38 is stored in the computer. By executing the program, a computer that is a hardware resource and a program that is a software resource are realized in cooperation with each other.

  The second two-phase heat flow analysis device 10B includes a macro in addition to the fluid calculation unit 12, the quality calculation unit 13, the physical property value calculation unit 14, and the calculation end determination unit 15 included in the first two-phase heat flow analysis device 10A. A fluid calculation unit 36, a first conversion processing unit 37, and a second conversion processing unit 38 are further provided.

  4 is conversion processing information including information such as an expression or a table used by the first conversion processing unit 37 and the second conversion processing unit 38 to perform parameter conversion processing. . The conversion processing information 39 is stored, for example, in a data storage area readable by a computer that executes the second two-phase heat flow analysis program.

  The macrofluidic calculation unit 36 equalizes the flow velocity, pressure, enthalpy, and void fraction (gas volume fraction) of the two-phase flow in the two divided areas, that is, the boundary between the boiling calculation region 32 and the macrofluidic calculation region 33. The macro fluid calculation for calculating the flow velocity, pressure, enthalpy and void fraction of the two-phase flow in the macro fluid calculation region 33 is performed. The boundary condition given to the macro fluid calculation unit 36 is that the first conversion processing unit 37 performs macro fluid calculation on parameters including at least the fluid flow velocity, pressure, and enthalpy in the boiling calculation region 32 which is the other region. It is given by converting the required fluid flow rate, pressure, enthalpy and void fraction into parameters.

  Further, the fluid calculation unit 12 is given a boundary condition that the flow velocity, pressure, enthalpy, and void fraction of the two-phase flow at the boundary between the boiling calculation region 32 and the macro fluid calculation region 33 are equal, and the fluid in the boiling calculation region 32 The flow velocity, pressure, and enthalpy are calculated. The boundary condition given to the fluid calculation unit 12 is given by the second conversion processing unit 38 converting it into parameters including at least the fluid flow velocity, pressure, enthalpy, and void fraction in the macro fluid calculation region 33 which is the other region. It is done.

  The results obtained by the fluid calculation unit 12 and the macro fluid calculation unit 36 are input to the calculation end determination unit 15, and it is determined whether or not both results satisfy a predetermined calculation end condition.

  As described above, the second two-phase heat flow analysis device 10B is compared with the first two-phase heat flow analysis device 10A, and the boiling calculation region where the entire region to be analyzed is located within a predetermined range from the heat source region. 32 and a macro fluid calculation area 33 outside the boiling calculation area 32, and the fluid calculation section 12, the mass flow rate calculation section 13, and the physical property value calculation section 14 are divided into the density and viscosity of the two-phase flow in the boiling calculation area 32. And at least one physical property value of thermal conductivity is different.

  Further, the second two-phase heat flow analysis device 10B is a macro that calculates the flow velocity, pressure, enthalpy, and void fraction of the two-phase flow in the macrofluid calculation region 33 with respect to the first two-phase heat flow analysis device 10A. The flow rate, pressure and enthalpy of the two-phase flow in the boiling calculation region 32 calculated by the fluid calculation unit 36 and the fluid calculation unit 12, and the density, viscosity and the two-phase flow in the boiling calculation region 32 calculated by the physical property value calculation unit 14 The relationship between at least one physical property value of thermal conductivity and at least one physical property value of density, viscosity, and thermal conductivity of the two-phase flow stored in the data storage area and the void ratio of the two-phase flow. Based on the conversion processing information 39 having the prescribed information, the void fraction of the two-phase flow at the boundary between the boiling calculation area 32 and the macrofluid calculation area 33 is obtained, and the boundary condition at the boundary is determined. With reference to the first conversion processing unit 37 given to the fluid calculation unit 36 and the conversion processing information 39 stored in the data storage area, the void fraction of the two-phase flow calculated by the macro fluid calculation unit 36 is calculated. It differs in that it further comprises a second conversion processing unit 38 that converts it into a physical property value of at least one of density, viscosity, and thermal conductivity and gives it to the fluid calculation unit 12.

  Subsequently, a second two-phase heat flow analysis method which is an example of the two-phase heat flow analysis method according to the second embodiment of the present invention will be described.

  FIG. 5 is an example of a second two-phase heat flow analysis method, and is a process flow diagram showing a process procedure of a second two-phase heat flow analysis procedure performed by the second two-phase heat flow analysis apparatus 10B.

  The second two-phase heat flow analysis procedure is different from the first two-phase heat flow analysis procedure in the macro fluid calculation step (step S12), the first parameter conversion processing step (step S11), and the second It differs in that it further includes a parameter conversion processing step (step S13) and a calculation end determination step (step S14) instead of the calculation end determination step (step S4). Therefore, in the description of the second two-phase heat flow analysis procedure, the difference from the first two-phase heat flow analysis procedure described above will be mainly described, and the same processing steps will be described with the same step numbers. Omitted.

  The second two-phase heat flow analysis procedure includes a boiling calculation region analysis step (steps S1 to S3) for calculating physical property values such as density, viscosity, thermal conductivity, specific heat of the two phases in the boiling calculation region 32, macro A macro fluid calculation region analysis step (step S12) for calculating physical property values such as density, viscosity, thermal conductivity, and specific heat of the two phases in the fluid calculation region 33, a boiling calculation region analysis step, and a macro fluid calculation region analysis step. A parameter conversion step (step S11, step S13) for converting parameters between each other. Further, the second two-phase heat flow analysis procedure includes a calculation end determination step (step S14).

  When the processing execution request of the second two-phase heat flow analysis procedure and the input of the initial parameters necessary for the calculation after step S1 are received, the execution of the processing procedure is started (START), the boiling calculation region analysis step, the macro fluid The calculation domain analysis process is started.

In the boiling calculation region analysis step, a fluid calculation step (step S1), a quality calculation step (step S2), and a physical property value calculation step (step S3) are sequentially executed, and input in the physical property value calculation step (step S3). On the other hand, when the density, viscosity, thermal conductivity, specific heat and the like, which are physical property values after one time step, are calculated, the boiling calculation region analysis step is completed. In executing the fluid calculation step (step S1), the flow velocity, pressure, and enthalpy of the two-phase flow at the boundary between the boiling calculation region 32 and the macro fluid calculation region 33 converted by the second conversion processing unit 38 are determined. The boundary condition is given to the fluid calculation unit 12 (B shown in FIG. 5).

  When the boiling calculation region analysis process is completed, the first conversion processing unit 37 executes the parameter conversion process. That is, a first parameter conversion processing step (step S11) is performed in which the first conversion processing unit 37 converts the parameter calculated in the boiling calculation region analysis step into a parameter necessary for execution of the macro fluid calculation region analysis step. Run.

  In the first parameter conversion processing step, the first conversion processing unit 37 refers to the conversion processing information 39 to set parameters including at least the fluid flow velocity, pressure, and enthalpy in the boiling calculation region 32 in the macro fluid calculation region 33. The flow rate, pressure, enthalpy, and void fraction necessary for performing the macrofluidic calculation are converted into parameters including at least.

  More specifically, the first conversion processing unit 37 determines the physical property value in the boiling calculation region 32 calculated by the physical property value calculating unit 14, and information on the formula (4) that defines the relationship between the density and the void fraction, for example. The void ratio is calculated with reference to the conversion processing information 39 including information defining the relationship between the physical property value and the void ratio. Then, the first conversion processing unit 37 calculates the calculated void ratio together with the flow velocity, pressure, and enthalpy of the two-phase flow at the boundary between the boiling calculation region 32 and the macro fluid calculation region 33 obtained in the boiling calculation region analysis step. This is given to the macro fluid calculation unit 36.

  In the first parameter conversion processing step (step S11), the first conversion processing unit 37 sets the boundary conditions between the boiling calculation region 32 and the macrofluid calculation region 33 as the flow rate, pressure, enthalpy of the two-phase flow at the boundary. When the void ratio is given to the macro fluid calculation unit 36, the process is completed. If step S11 is completed, it will progress to step S14 and the calculation end determination part 15 will perform a calculation end determination step.

  In the calculation end determination step (step S14), the calculation end determination unit 15 determines whether or not a predetermined calculation end condition is satisfied, and if it is determined to satisfy (if YES in step S14), the second The two-phase heat flow analysis procedure ends (END).

  On the other hand, when the calculation end determination unit 15 determines that the predetermined calculation end condition is not satisfied (NO in step S14), the process returns to step S1 and step S12 (C shown in FIG. 5), and after step S1. And the process step after step S12 is repeated. That is, the boiling calculation region analysis step (step S1 to step S3) and the macro fluid calculation region analysis step (step S12) after the next one time step are executed.

  In the macro fluid calculation region analysis step, the macro fluid calculation unit 36 performs macro fluid calculation on the fluid flowing in the macro fluid calculation region 33, and calculates the flow velocity, pressure, enthalpy and void ratio (gas volume ratio) of the fluid. A fluid calculation step is executed (step S12). Of the parameters required for calculating the macro fluid, the void ratio (gas volume ratio) is a value calculated based on information defining the relationship between the physical property value and the void ratio included in the conversion processing information 39. Is used (A shown in FIG. 5).

  When the flow velocity, pressure, enthalpy and void ratio of the fluid flowing in the macro fluid calculation area 33 are calculated, the macro fluid calculation area analysis process is completed. When the macro fluid calculation region analysis step is completed, the second conversion processing unit 38 executes the parameter conversion step. That is, the second conversion processing unit 38 performs a second parameter conversion processing step (step S13) in which the parameter calculated in the macro fluid calculation region analysis step is converted into a parameter necessary for execution of the boiling calculation region analysis step. Run.

  In the second parameter conversion processing step (step S13), the second conversion processing unit 38 sets the flow velocity, pressure, and enthalpy of the two-phase flow at the boundary as boundary conditions between the boiling calculation region 32 and the macro fluid calculation region 33. When it is given to the fluid calculation unit 12, it is completed. When step S13 is completed, the process proceeds to step S14, and the calculation end determination unit 15 executes a calculation end determination step.

  According to the second two-phase heat flow analysis device 10B and the second two-phase heat flow analysis method, two-phase flow phenomena such as boiling heat transfer or condensation heat transfer can be directly evaluated without using a constitutive equation. . The region near the wall surface where the phase change phenomenon such as the boiling phenomenon occurs (boiling calculation region 32) directly evaluates the phase change phenomenon such as the boiling phenomenon, and the region away from the wall surface (macro fluid calculation region 33) is the two-fluid. By applying the macro fluid calculation by the model, it is possible to analyze efficiently.

  As described above, according to the two-phase heat flow analysis device and analysis method according to the embodiment of the present invention, boiling heat transfer, condensation heat transfer, or the like, for a fluid such as water, without using a constitutive equation or a flow pattern map, etc. The two-phase flow phenomenon can be directly evaluated. Further, in the embodiment in which the macro fluid calculation based on the two-fluid model is applied by setting the area away from the heating (cooling) wall surface 31 as the macro fluid calculation area 33, a wider area can be efficiently analyzed.

  It should be noted that the present invention is not limited to the above-described embodiment as it is, and can be implemented in various forms other than the above-described examples in the implementation stage, and various modifications can be made without departing from the spirit of the invention. Can be omitted, added, replaced, or changed. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

10A First two-phase heat flow analysis device 10B Second two-phase heat flow analysis device 11 Input unit 12 Fluid calculation unit 13 Quality calculation unit (mass flow rate fraction calculation unit)
14 Physical property value calculation unit 15 Calculation end determination unit 16 Display unit 21 Quality calculation information 22 Physical property value calculation information 31 Heating wall surface (heat source region)
32 Boiling calculation area (first area)
33 Macro fluid calculation area (second area)
36 Macro fluid calculation unit 37 First conversion processing unit 38 Second conversion processing unit 39 Conversion processing information BL Calculation region boundary

Claims (6)

For a plurality of sections into which the flow field is divided, the shape data of the analysis target given from the input unit, the range of the heat source region where heat enters and exits, the boundary condition between this heat source region and other regions, and the two analysis targets A fluid calculation unit for calculating the flow velocity, pressure, and enthalpy of the two-phase flow based on initial parameters including initial values of physical properties including phase flow velocity, pressure, enthalpy and density, viscosity, and thermal conductivity;
Formula information for calculating the mass flow rate fraction of the two-phase flow stored in the data storage area based on the pressure and enthalpy of the two-phase flow calculated by the fluid calculation unit for the plurality of sections, and the state A mass flow rate calculation unit for calculating the mass flow rate fraction of the two-phase flow with reference to the information of the equation;
For the plurality of sections, referring to the information of the state equation stored in the data storage area, the physical property values including the density, viscosity and thermal conductivity of each phase constituting the two-phase flow are obtained, while in the data storage area Referring to the mathematical formula information for calculating the physical property value of the two-phase flow stored, the physical property value of each phase constituting the two-phase flow and the mass flow rate fraction of the two-phase flow calculated by the mass flow rate calculation unit Based on the physical property value calculation unit for calculating physical property values including the density, viscosity and thermal conductivity of the two-phase flow,
A calculation end determination unit that determines whether or not the calculation end condition is satisfied based on the flow velocity, pressure, and enthalpy of the two-phase flow calculated by the fluid calculation unit, and a preset calculation end condition;
The entire region to be analyzed is divided into a first region located within a predetermined range from the heat source region and a second region located outside the predetermined range, and the fluid calculation unit, mass flow rate fraction While the calculation unit and the physical property value calculation unit are configured to calculate at least one physical property value of the density, viscosity, and thermal conductivity of the two-phase flow in the first region,
A macrofluidic calculator that calculates the flow velocity, pressure, enthalpy and void fraction of the two-phase flow in the second region;
The flow rate, pressure and enthalpy of the two-phase flow in the first region calculated by the fluid calculation unit, and the density, viscosity and heat conduction of the two-phase flow in the first region calculated by the physical property value calculation unit. Stipulates the relationship between at least one physical property value of the rate and at least one of the physical property value of the two-phase flow stored in the data storage area and the void rate of the two-phase flow Based on the obtained information, the physical property value calculation unit calculates at least one physical property value of the density, viscosity, and thermal conductivity of the two-phase flow in the first region to the void ratio of the two-phase flow. A first conversion processing unit that converts and gives the macrofluidic calculation unit;
Reference is made to information defining the relationship between at least one physical property value of the density, viscosity and thermal conductivity of the two-phase flow stored in the data storage area and the void ratio of the two-phase flow, and the macro fluid calculation unit Converting the void fraction of the two-phase flow calculated into a physical property value of at least one of the density, viscosity, and thermal conductivity of the two-phase flow and giving the fluid calculation unit a second conversion processing unit; A two-phase heat flow analysis apparatus comprising: The two-phase flow, two-phase heat flow analysis apparatus according to claim 1, characterized in that the gas-liquid two-phase flow composed of a liquid phase and a gas phase. The two-phase heat flow analysis apparatus according to claim 1 or 2 , wherein the heat source region is a heating region that receives heat from the outside in the two-phase flow to be analyzed. The two-phase heat flow analysis apparatus according to claim 1 or 2 , wherein the two-phase flow is a solid-liquid two-phase flow composed of a liquid phase and a solid phase . The two-phase heat flow analysis apparatus according to any one of claims 1 to 3, wherein the heat source region is a cooling region that takes heat from the two-phase flow to be analyzed. It is a method to predict the heat flow phenomenon of two-phase flow using a computer,
The fluid calculation unit has, for a plurality of sections obtained by dividing the flow field, the shape data of the analysis target given from the input unit, the range of the heat source region where heat enters and exits, the boundary condition between this heat source region and other regions, Fluid calculation to calculate the flow velocity, pressure and enthalpy of the two-phase flow based on the initial parameters including the flow velocity, pressure and enthalpy of the two-phase flow to be analyzed and the initial values of physical properties including density, viscosity and thermal conductivity Steps,
The mass flow rate fraction of the two-phase flow stored in the data storage area based on the pressure and enthalpy of the two-phase flow calculated in the fluid calculation step for the plurality of sections by the mass flow rate calculation unit A mass flow rate calculation step for calculating a mass flow rate fraction of the two-phase flow with reference to mathematical formula information for calculating the information and information on the state equation;
The physical property value calculation unit obtains physical property values including the density, viscosity, and thermal conductivity of each phase constituting the two-phase flow with reference to the state equation information stored in the data storage area for the plurality of sections. On the other hand, referring to the mathematical formula information for calculating the physical property value of the two-phase flow stored in the data storage area, the physical property value of each phase constituting the two-phase flow and the two-phase flow calculated in the mass flow rate calculation step A physical property value calculating step for calculating a physical property value including the density, viscosity and thermal conductivity of the two-phase flow based on the mass flow rate fraction of the flow,
The entire region to be analyzed is divided into a first region located within a predetermined range from the heat source region and a second region located outside the predetermined range, and the fluid calculation unit, mass flow rate fraction While the calculation unit and the physical property value calculation unit are configured to calculate at least one physical property value of the density, viscosity, and thermal conductivity of the two-phase flow in the first region,
A macrofluid calculation step in which a macrofluid calculation unit calculates the flow velocity, pressure, enthalpy and void fraction of the two-phase flow in the second region;
The first conversion processing unit calculates the two-phase flow velocity, pressure, and enthalpy in the first region calculated by the fluid calculation unit, and the two-phase in the first region calculated by the physical property value calculation unit. At least one physical property value of flow density, viscosity, and thermal conductivity, and at least one physical property value of density, viscosity, and thermal conductivity of the two-phase flow stored in the data storage area and the two-phase flow On the basis of the information defining the relationship with the void ratio of at least one of the physical property value of the density, viscosity and thermal conductivity of the two-phase flow in the first region calculated by the physical property value calculation unit. A first conversion processing step for converting into the void fraction of the two-phase flow and providing the macrofluidic calculation unit;
Information defining the relationship between at least one physical property value of the density, viscosity and thermal conductivity of the two-phase flow stored in the data storage area and the void ratio of the two-phase flow is stored in the data storage area. The void ratio of the two-phase flow calculated by the macro fluid calculation unit is converted into at least one physical property value of the density, viscosity, and thermal conductivity of the two-phase flow and is given to the fluid calculation unit. Two conversion processing steps;
The calculation end determination unit is configured to calculate the flow velocity, pressure, and enthalpy of the two-phase flow in the first region calculated in the fluid calculation step, and the two-phase flow in the second region calculated in the macro fluid calculation step. A calculation end determination step for determining whether or not the calculation end condition is satisfied based on a flow rate, a pressure, an enthalpy and a void ratio, and a preset calculation end condition. Phase heat flow analysis method .