Method for calculating flow rate and quality, and program for calculating flow rate and quality

Abstract

To obtain injection outlet flow rate and quality that strictly satisfy energy conservation formulas of thermodynamics and hydrodynamics in gas-liquid two-phase jet flow.SOLUTION: A method for calculating flow rate and quality of gas-liquid two-phase jet flow ejected from an injection outlet into which liquid flows includes: a step S1 of obtaining mass flow rate and specific enthalpy of liquid; a step S2 of obtaining specific volume and specific enthalpy of gas phase and liquid phase of the gas-liquid two-phase jet flow; a step S3 of calculating mass flow rate of the gas phase of the gas-liquid two-phase jet flow at an injection outlet; and a step S4 of calculating flow rate and quality of the gas-liquid two-phase jet flow.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present disclosure relates to a method for calculating flow velocity and quality, and a program for calculating flow velocity and quality.

Background Art

[0002] A technique has been proposed in which liquid fuel is depressurized and boiled while being sprayed into the combustion chamber of an internal combustion engine to achieve efficient mixing with air (see, for example, Non-Patent Document 1).

[0003] A technique has been proposed in which cleaning is performed with a jet in which water droplets are dispersed in water vapor (see, for example, Non-Patent Document 2).

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] A gas-liquid two-phase flow (i.e., a flow of a mixture of gas and liquid) consisting of a single component such as wet steam (i.e., steam containing water droplets) undergoes evaporation and condensation triggered by heat transfer with the external environment or a pressure change. Therefore, the mass content ratios of the gas and liquid easily change. Hereinafter, in this specification, the mass fraction of the gas in the total amount of the fluid in the gas-liquid two-phase flow is referred to as "quality". That is, the quality x in the gas-liquid two-phase flow is defined as follows. x = mass of gas / (mass of gas + mass of liquid)

[0006] Generally, gas-liquid two-phase flows often fall outside the measurement targets of general-purpose flow meters and velocity meters. At this time, not only the mixing fraction of the gas and liquid, but also the flow pattern varies greatly depending on the mixing form, so there is a problem that it is very difficult to grasp its flow state.

[0007] Furthermore, in the case of a single-component gas-liquid two-phase flow, due to the accompanying evaporation and condensation, it becomes even more difficult to grasp the state compared to a gas-liquid two-phase flow of different components. For example, in the case of a gas-liquid two-phase flow of different components, generally no mass transfer occurs between the gas phase and the liquid phase, so the gas-liquid ratio is basically constant in a closed space. In contrast, in a single-component gas-liquid two-phase flow, the mixing fraction of the gas and liquid easily changes due to evaporation and condensation. Furthermore, in the case of a gas-liquid two-phase flow of different components, the density of the fluid can be known based on the state equation by measuring the temperature and pressure. In contrast, in a single-component gas-liquid two-phase flow, in principle, the temperature and pressure are restricted to the values of the saturated state, and the mixing fraction of the gas and liquid changes independently of them. Therefore, it is also impossible to grasp the state using the temperature and pressure as clues.

[0008] For example, in a single-component gas-liquid two-phase jet, consider the change in the flow pattern when the quality is changed while keeping the total mass flow rate of the gas phase and the liquid phase constant. At this time, as the quality changes, all aspects characterizing the flow of the jet, such as the flow velocity, the consumed / output energy, and the spray range, change dramatically. For example, the higher the quality (the mass fraction of the gas), the higher the flow velocity, the higher the energy, the wider the spray range, and the shorter the reach distance. Conversely, the lower the quality, the lower the flow velocity, the lower the energy, the narrower the spray range, and the longer the reach distance.

[0009] As described above, it is difficult to grasp, predict, and control the flow state of a jet in which a gas and a liquid of the same component are mixed. However, on the other hand, if a control method is constructed, it becomes possible to actively and widely change the flow state, so various engineering applications are being studied. Applications of this type of jet include "fields where a flow accompanied by evaporation / condensation is artificially generated, actively controlled, and applied industrially," such as fuel injection into internal combustion engines, liquid rockets, and cleaning machines, and "fields where passive safety measures are taken against a depressurization boiling jet that occurs spontaneously unintentionally," such as safety measures in the event of a leakage accident from pipes and containers of high-temperature high-pressure water or liquid hydrogen. In any case, it is necessary to predict and grasp the jet behavior in advance. At this time, it is extremely important to obtain the flow velocity and gas-liquid ratio at the jet outlet as boundary conditions that determine the jet behavior.

[0010] The technology disclosed in Non-Patent Document 1 promotes atomization of fuel by inducing depressurization boiling in the spray of liquid fuel in an internal combustion engine, thereby realizing combustion under good conditions. The values of the flow velocity and quality at the jet outlet are important parameters that determine the jet behavior. However, a theoretical solution that satisfies the energy conservation of thermodynamics and fluid dynamics without contradiction for these parameters has not yet been obtained.

[0011] The technology disclosed in Non-Patent Document 2 is a technology for obtaining a high cleaning effect by spraying an object with a jet of water vapor (wet steam) containing water droplets generated by merging liquid water into a water vapor jet. The flow velocity and quality at the jet outlet are important parameters that determine the performance of the device, but there are no cases in this field where the cleaning effect has been evaluated based on a theoretical solution of these parameters.

[0012] The technology disclosed in Non-Patent Document 3 captures the vaporization phenomenon occurring inside a heat exchanger for cooling with evaporation, which has been undergoing remarkable miniaturization and reduction in diameter in recent years, as cavitation, and clarifies the relationship between the "thermodynamic self-suppression effect" and the "wall heating effect (promotion effect)". The elucidation of phenomena in this field is carried out by organizing experimental results based on dimensionless numbers representing the "ease of cavitation occurrence" and the "magnitude of the thermodynamic self-suppression effect". However, there are still no cases where the phenomenon has been elucidated by a theoretical solution that satisfies the energy conservation of thermodynamics and fluid dynamics without contradiction.

[0013] Thus, although it is important to obtain the flow velocity and liquid-gas ratio (quality) at the jet outlet in order to predict and grasp the behavior of the jet in advance, the prior art has not been able to achieve this.

[0014] This disclosure has been made in view of such circumstances, and its object is to obtain a jet outlet flow velocity and quality that strictly satisfy the energy conservation equations of thermodynamics and fluid dynamics in a gas-liquid two-phase jet.

Means for Solving the Problem

[0015] To solve the above problems, an aspect of the present disclosure is a method for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a jet orifice into which a liquid flows. This method includes steps of obtaining the mass flow rate and specific enthalpy of the liquid, obtaining the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase jet, calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet at the jet orifice, and calculating the flow velocity and quality of the gas-liquid two-phase jet. The step of calculating the mass flow rate of the gas phase performs the calculation using

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[0016] In one embodiment, the specific enthalpy of the liquid may be calculated from the initial temperature and initial pressure of the liquid.

[0017] In one embodiment, the flow path through which the liquid flows into the nozzle exit may be insulated.

[0018] In one embodiment, the flow in the cross-section of the nozzle exit may be a uniform dispersion flow in which the liquid phase and the gas phase flow out at a uniform flow velocity.

[0019] In one embodiment, the state at the nozzle exit may be a gas-liquid two-phase state due to flashing.

[0020] Yet another aspect of the present disclosure is also a method. This method is a method for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a two-fluid nozzle of a jet generator including a gas supply mechanism, a liquid supply mechanism, and a two-fluid nozzle that combines a gas and a liquid to atomize the liquid. This method includes steps of obtaining the mass flow rate and specific enthalpy of the liquid and gas flowing into the two-fluid nozzle, obtaining the specific volume and specific enthalpy of each of the gas phase and the liquid phase of the gas-liquid two-phase jet, calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet in the two-fluid nozzle, and calculating the flow velocity and quality of the gas-liquid two-phase jet. The step of calculating the mass flow rate of the gas phase is

Equation

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[0021] Another aspect of the present disclosure is also a method. This method is a method for calculating the flow velocity and quality of a fluid passing through a pipe provided with a heating mechanism or a cooling mechanism between a first position and a second position downstream of the first position. The fluid is a liquid at the first position and a gas-liquid two-phase fluid at the second position. This method includes steps of obtaining the mass flow rate and specific enthalpy of the fluid at the first position, obtaining the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase fluid, calculating the mass flow rate of the gas phase of the gas-liquid two-phase fluid at the second position, and calculating the flow velocity and quality of the gas-liquid two-phase fluid. The step of calculating the mass flow rate of the gas phase is [Number] performed using. The step of calculating the flow velocity and quality is [Number] [Number] [Number] performed using. [Number] represents the mass flow rate of the fluid at the first position. [Number] represents the mass flow rate of the gas phase of the gas-liquid two-phase fluid at the second position. [Number] represents the mass flow rate of the liquid phase of the gas-liquid two-phase fluid at the second position. [Number] is the heating amount per unit time from the outside, indicating that the fluid is heated from the outside when it is positive and cooled from the outside when it is negative. h1 represents the specific enthalpy of the fluid at the first position. ν V2 represents the specific volume of the gas phase in the two-fluid nozzle. ν L2 represents the specific volume of the liquid phase in the two-fluid nozzle. h V2 represents the specific enthalpy of the gas phase in the two-fluid nozzle. h L2 represents the specific enthalpy of the liquid phase in the two-fluid nozzle. A represents the cross-sectional area at the second position. u2 represents the flow velocity at the second position. x2 represents the quality at the second position.

[0022] Still another aspect of the present disclosure is a program for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a jet orifice into which a liquid flows. This program causes a computer to execute a method including steps of acquiring the mass flow rate and specific enthalpy of the liquid, acquiring the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase jet, calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet at the jet orifice, and calculating the flow velocity and quality of the gas-liquid two-phase jet. The step of calculating the mass flow rate of the gas phase is

Equation

Equation

Equation

Equation

[0023] Yet another aspect of the present disclosure is also a program. This program is a program for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a two-fluid nozzle of a jet generator including a gas supply mechanism, a liquid supply mechanism, and a two-fluid nozzle that combines gas and liquid to atomize the liquid. This program causes a computer to execute a method including: a step of obtaining the mass flow rate and specific enthalpy of the liquid and gas flowing into the two-fluid nozzle; a step of obtaining the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase jet; a step of calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet in the two-fluid nozzle; and a step of calculating the flow velocity and quality of the gas-liquid two-phase jet. The step of calculating the mass flow rate of the gas phase is

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[0024] Yet another aspect of the present disclosure is also a program. This program is a program for calculating the flow velocity and quality of a fluid passing through a pipe provided with a heating mechanism or a cooling mechanism between a first position and a second position downstream of the first position. The fluid is liquid at the first position and a gas-liquid two-phase fluid at the second position. This program causes a computer to execute a method including steps of acquiring the mass flow rate and specific enthalpy of the fluid at the first position, acquiring the specific volume and specific enthalpy of each of the gas phase and the liquid phase of the gas-liquid two-phase fluid, calculating the mass flow rate of the gas phase of the gas-liquid two-phase fluid at the second position, and calculating the flow velocity and quality of the gas-liquid two-phase fluid. The step of calculating the mass flow rate of the gas phase is

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[0025] In addition, any combination of the above components, and those obtained by converting the expressions of the present disclosure among methods, apparatuses, systems, recording media, computer programs, etc., are also effective as aspects of the present disclosure.

Advantages of the Invention

[0026] According to the present disclosure, in a gas-liquid two-phase jet, it is possible to obtain an outlet flow velocity and a quality that strictly satisfy the energy conservation equations of thermodynamics and fluid mechanics.

Brief Description of the Drawings

[0027]

Figure 1

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Figure 12

Mode for Carrying Out the Invention

[0028] [First Embodiment] [Principle] FIG. 1 is a schematic diagram of a thermodynamic model describing the vacuum boiling according to the first embodiment of the present disclosure. The example shown here is a jet generating device 1 including a liquid storage tank (container), and a jet outlet is provided at the lower part of the container. A high-temperature and high-pressure fluid is stored in the upper part of the jet generating device 1 in a fully liquid phase state, and a gas-liquid mixed-phase jet is formed by vacuum boiling when it jets out from the jet outlet at the lower part of the container. [Number] (hereinafter referred to as "M dot") is the total mass flow rate of the gas phase and the liquid phase, [Number] (hereinafter referred to as "m dot") are the mass flow rates of the gas phase and the liquid phase respectively, p is the pressure, T is the temperature, h is the specific enthalpy, A is the opening area of the nozzle outlet, u is the flow velocity, and x is the quality. The gas phase is represented by V and the liquid phase is represented by L, and subscripts are attached to each physical quantity with the thermodynamic state of the liquid before ejection being state 1 and the thermodynamic state of the nozzle outlet cross-section being state 2. The pressure p1 of the liquid in the initial storage state is higher than the ambient environmental pressure p atm for ejection to the outside, and since it is the liquid phase, the temperature T1 must be lower than the saturation temperature of the pressure p1. Since the state 2 of the nozzle outlet becomes a gas-liquid mixed phase by flashing, it is regarded as the saturation state at the ambient environmental pressure p atm . Furthermore, prior to the derivation of the governing equation, the following are assumed. 1. The flow is in a steady state. 2. To ensure the law of conservation of energy, the flow path is completely insulated. 3. The flow at the nozzle outlet cross-section is a uniform dispersion flow in which water and steam flow out at a uniform flow velocity. 4. The mixed water and steam reach thermal equilibrium at the nozzle outlet and are in a saturated state.

[0029] In the model of FIG. 1, the following law of conservation of mass holds. [Number] Here, M dot is the total mass flow rate of the fluid to be ejected. [Number] (hereinafter referred to as "m V2 dot") and [Number] (hereinafter referred to as "m L2(which is denoted as "dot") is the mass flow rate of the vapor and the liquid at the jet outlet, respectively.

[0030] Furthermore, the following law of conservation of energy holds.

Equation

[0031] From the perspective of fluid mechanics, the energy conservation equation (2) can be said to be obtained by ignoring the potential energy and taking into account the internal energy from Bernoulli's equation (conservation of pressure energy + kinetic energy + potential energy, that is, the conservation equation of mechanical energy). On the other hand, from the perspective of thermodynamics, the energy conservation equation (2) can be interpreted as taking into account the kinetic energy in the nozzle in addition to the first law of thermodynamics in a steady flow system (conservation of internal energy + pressure energy, that is, the conservation equation of enthalpy). The pressure p1 upstream of the jet outlet is higher than the ambient environmental pressure p atm Therefore, the existence of pressure loss is also considered when passing through the nozzle in this model. Here, the pressure loss refers to the phenomenon in which pressure energy is converted into thermal energy. In the case of the ordinary Bernoulli's theorem that does not consider thermal energy, an energy dissipation term that balances the pressure energy that disappears from the model by being converted into heat must be added for the conservation of energy to hold. On the other hand, the enthalpy term of the energy conservation equation (2) used in this embodiment includes the internal energy, which is the recipient of thermal energy. Therefore, it holds exactly even without the dissipation term. That is, the reason why the dissipation term is not included in Equation (2) is not that it is arbitrarily ignored, but that it holds exactly even without it.

[0032] Furthermore, similar to general in-pipe flow, since the flow velocity u2 at the jet outlet is obtained by dividing the volumetric flow rate by the cross-sectional area, the following equation holds.

Equation

[0033] Substituting the mass conservation equation (1) and equation (3) into the energy conservation equation (2) and transforming it, these simultaneous equations ultimately reduce to a quadratic equation for the mass flow rate m V2 dot of the gas phase at the jet outlet, that is, the mass of the fluid vaporized per unit time.

Equation

[0034] Here, consider the individual physical quantities included in equation (4). Since the specific enthalpy h and the specific volume ν are thermodynamic state quantities, they are constants that can be obtained for substances with thermodynamic property data organized in a form such as a steam table, assuming that specific heat, latent heat, density, etc. are known. Also, the jet outlet opening area A is a constant determined by the device specifications. The total mass flow rate M dot of the gas phase and the liquid phase ejected is a loss coefficient determined not only by the opening area of the jet outlet but also by the shape of the entire nozzle, and the differential pressure p1 - p atm, furthermore, it is determined by reflecting complex factors such as the gas-liquid mixing state inside the nozzle. Although it is difficult to predict in advance, it can be measured relatively easily if experiments can be carried out. Even when experiments cannot be conducted, in addition to the choke phenomenon where the flow velocity is restricted to the speed of sound in the nozzle flow in the sonic velocity range, the speed of sound in the gas-liquid two-phase flow is correlated with the void fraction (volume fraction of the gas phase), and it is known that the speed of sound can be extremely low depending on the conditions. Therefore, although it is difficult to predict the flow rate, it is expected that the knowledge of the nozzle flow in the sonic velocity range in these fields of compressible fluid dynamics will be useful for estimation. By measuring, estimating, or assuming the total mass flow rate M dot of the gas phase and the liquid phase by any of the above methods, Equation (4) becomes a quadratic equation with only the evaporation rate m V2 dot as the unknown. Therefore, it can be solved analytically.

[0035] Substituting m V2 dot obtained by solving (4) into the mass conservation equation (1), the mass flow rate m L2 dot of the liquid phase at the nozzle exit can be obtained. Furthermore, by substituting the solutions of m V2 dot and m L2 dot into Equation (3), the theoretical solution of the flow velocity u2 at the nozzle exit can be obtained, and the theoretical solution of the quality x2 at the nozzle exit defined as the mass fraction of the gas phase can be calculated by the following equation. [Number]

[0036] Figure 2 shows the derivation and solution procedure of Equation (4). However, in Figure 2, the case where Q dot (described later) is zero in particular is the present embodiment. Therefore, Equations (2) and (4) correspond to those obtained by setting Q dot in Equations (10) and (11) to zero, respectively (the same applies hereinafter). In the figure, "Determine the target substance", "Determine the initial temperature T1", "Determine the initial pressure p1", "Determine the nozzle shape", and "Ambient environmental pressure p atmPerform "determination", set the total mass flow rate \(\dot{M}\) of the gas phase and the liquid phase, and further create thermodynamic property data such as the "saturation table" and the "compressed liquid and superheated steam table" of the target substance shown in the upper left of the figure as necessary. Then, by performing calculations along the arrow, the theoretical solutions for the flow velocity \(u_2\) and quality \(x_2\) at the nozzle exit can be obtained.

[0037] [Example of theoretical solution] Using the physical properties of pure water as the target substance, the velocity \(u_2\) and quality \(x_2\) at the nozzle exit calculated by Eqs. (3) to (5) were obtained. Figures 3 and 4 show the calculated velocity \(u_2\) and quality \(x_2\), respectively. The horizontal axes of Figures 3 and 4 represent the temperature \(T_1\) of the liquid in the initial storage state (state 1) upstream of the nozzle exit. Also, the saturation temperatures at 1, 5, 10, and 15 MPa are shown as auxiliary lines (vertical lines). Since these values are the upper limit temperatures at which water can exist while maintaining the liquid phase, they represent the upper limit of the temperature \(T_1\) that can be set at each initial storage pressure \(p_1\). In this calculation, assuming the high-pressure water piping of a nuclear power plant as the most severe condition, the upper limit of \(p_1\) was set to 350 °C according to the saturation temperature at 15 MPa. The ambient environmental pressure \(p\) atm , the nozzle opening area \(A\) was set to \(A = 1.2×10\) -5 [m 2 , \(p\) atm = 0.1013 [MPa] (atmospheric pressure). The values of the specific enthalpy \(h\) and specific volume \(\nu\), which are the thermodynamic properties of water (liquid) and steam in each state included in Eq. (4), were obtained using the "Steam Tables" of the Japan Society of Mechanical Engineers. Since the thermodynamic state (state 2) of the nozzle exit is regarded as the saturation state at the ambient environmental pressure, \(h\) V2 , \(h\) L2 , \(\nu\) V2 , \(\nu\) L2 were each quoted from the "saturation table" as the value at 0.1013 [MPa]. The specific enthalpy \(h_1\) of the compressed water upstream of the nozzle exit (state 1) was quoted by specifying the temperature \(T_1\) and pressure \(p_1\) of that state from the "compressed liquid and superheated steam table" included in the steam tables.

[0038] This temperature and pressure are set parameters that form the basic conditions for flash boiling and are determined by the object to which the model is applied. As an example, Fig. 5 shows the relationship between the specific enthalpy of compressed water, temperature, and pressure cited from the steam table. From this figure, it can be seen that the specific enthalpy of compressed water is approximately proportional to the Celsius temperature with the specific heat of water (liquid) (c L = 4.19 [kJ / (kg·K)]) as the proportionality constant and is almost independent of pressure over a wide range from 0.01 MPa to 15 MPa. Based on this, the value obtained by the following approximate formula (the straight line in Fig. 5) was used as the value of the specific enthalpy at the upstream of the nozzle (state 1). [Number]

[0039] Also, as described above, the total mass flow rate M· of the liquid phase and the gas phase is determined by reflecting complex factors such as the shape of the entire nozzle, the differential pressure p1 - p atm between the upstream and downstream of the nozzle outlet, the gas-liquid mixing state, and the choking phenomenon in the sonic region, so it is difficult to predict in advance. Therefore, it was widely varied as a parameter at the calculation stage.

[0040] According to Fig. 3, it can be seen that the theoretical flow velocity u2 at the nozzle outlet not only increases monotonically with the increase in the total mass flow rate M· of the liquid phase and the gas phase but also increases monotonically with the increase in the compressed water temperature T1 at the upstream of the nozzle outlet (state 1). As shown in Fig. 5, this is because the specific enthalpy h1 of the compressed water at the upstream of the nozzle outlet (state 1) increases approximately proportionally to the Celsius temperature T1. When flash boiling occurs at the nozzle outlet (state 2), as the energy allocated to the latent heat of evaporation increases, the evaporation mass m V2 · per unit time increases, and as a result, the volume flow rate of the entire jet increases.

[0041] As expected from the above considerations, according to Fig. 4, the theoretical quality x2 at the nozzle exit increases with the increase in the compressed water temperature T1 upstream of the nozzle exit (state 1). Also, under the condition of a high flow velocity, that is, when M dot is large and the upstream temperature T1 of the nozzle exit is high, it can be read that the increase in the quality x2 becomes smaller with respect to the increase in T1. This is because as the flow velocity increases due to the increase in the mass flow rate M dot and the evaporation mass m V2 dot per unit time, the ratio of the kinetic energy (the third term) on the right side of the energy conservation equation (2) increases, and the amount of enthalpy that water and steam can hold (the first term + the second term) relatively decreases. As a result, it is considered that the ratio of the energy allocated to the latent heat of evaporation required for the steam to remain in the steam state decreases.

[0042] Furthermore, the auxiliary lines drawn as vertical lines in Figs. 3 and 4 represent the upper limits of the temperature T1 when the upstream pressure p1 of the nozzle exit is 1, 5, 10, and 15 MPa, respectively. Therefore, the values of the velocity u2 and the quality x2 under these conditions can be interpreted as showing one theoretical upper limit at each upstream pressure p1 of the nozzle exit. For example, regarding the substance water, when leakage occurs from a container or pipe containing water (liquid phase) at 1 MPa to the ambient environment at atmospheric pressure, the quality of the jet generated by spontaneous depressurization boiling can be estimated to be at most about 0.15 kg / kg.

[0043] [Second Embodiment] [Principle] Fig. 6 is a schematic diagram showing the principle of the second embodiment of the present disclosure. Fig. 6 includes a steam supply mechanism (more generally, a gas supply mechanism) including a pressure vessel equipped with a heater for steam generation, a water (liquid) supply system (more generally, a liquid supply mechanism), and a two-fluid nozzle that combines steam and water (more generally, gas and liquid) to atomize the liquid, which is a jet generation device 2.

[0044] The steam supply mechanism has an electric heater installed at the bottom of the pressure vessel. By adjusting the voltage applied to the heater, the amount of generated steam can be controlled. While the vacuum boiling model shown in Fig. 1 supplies only the liquid, this experimental apparatus can mix water (liquid) and steam with a two-fluid nozzle and generate jets under various conditions by adjusting the flow rates of each.

[0045] In the theoretical model of vacuum boiling shown in Fig. 1, since only the liquid phase flows in from the upstream, the left sides of the mass conservation equation (1) and the energy conservation equation (2) consist of only one term each for the mass flow rate and the enthalpy flow rate of the upstream liquid phase. In contrast, in the jet generation apparatus shown in Fig. 6, it is necessary to sum the values of the independently flowing water (liquid phase) and steam (gas phase) as the mass and enthalpy of the fluid flowing into the nozzle. Therefore, as follows, the left side is rewritten by dividing it into two terms.

Equation

Equation

[0046] The changed parts of equations (1) and (2) in equations (7) and (8) are only on the left side, and since this is a change that does not affect the derivation process of the quadratic equation (4) of m with a dot, the following equation is derived through exactly the same equation transformation. V2 By analytically solving equation (9) as a quadratic equation, the above flow rate m with a dot at the nozzle exit is obtained, and the velocity u2 and quality x2 at the nozzle exit can be calculated using equations (7), (3), and (5).

Equation

[0047] By analytically solving equation (9) as a quadratic equation, the above flow rate m with a dot at the nozzle exit is obtained, and the velocity u2 and quality x2 at the nozzle exit can be calculated using equations (7), (3), and (5). V2 By analytically solving equation (9) as a quadratic equation, the above flow rate m with a dot at the nozzle exit is obtained, and the velocity u2 and quality x2 at the nozzle exit can be calculated using equations (7), (3), and (5).

[0048] [Example of theoretical solution] Figures 7 and 8 respectively show the theoretical values of the flow velocity and quality at the nozzle exit positions obtained by formulas (9), (7), (3), and (5). These are the results calculated by fixing the specific enthalpy ratio of water vapor and water (liquid) in the initial storage state to the experimental values and varying the supply mass flow rates of water vapor and water (liquid).

[0049] It can be seen that the theoretical value of the flow velocity shown in Figure 7 increases as the supply amount of water vapor increases, while it decreases as the supply amount of water (liquid) increases. This is because as the inflow amount of water (liquid) into the nozzle increases, the condensation amount of water vapor accompanying the mixing increases, and the decrease in the volume flow rate accompanying the decrease in quality is reflected in the velocity. That is, in the theoretical model of this embodiment, the influence of the gas-liquid phase change caused by the heat transfer between water vapor and water (liquid) during mixing is reflected in the flow velocity and quality at the nozzle exit. From the calculation results of the quality shown in Figure 8, it can be seen that the quality increases monotonically as the supply amount of water vapor increases and the supply amount of water (liquid) decreases.

[0050] [Third Embodiment] Figure 9 is a schematic diagram showing the principle of the third embodiment of the present disclosure. Figure 9 is a pipe 3 through which a fluid passes inside, such as a heat pump. A heating mechanism for heating the fluid or a cooling mechanism for cooling the fluid is provided in the middle of the pipe 3.

[0051] Take the y-axis along the longitudinal direction of the pipe 3. A fluid with a mass flow rate of M dot flows through the pipe 3 in the positive direction along the y-axis.

[0052] Let the state at y = y1 be state 1. In state 1, all the fluid is liquid, with a temperature of T1 and a specific enthalpy of h1. For example, if the temperature T1 is measured using a thermometer, the specific enthalpy h1 can be obtained from physical property data or the like.

[0053] Between y1 < y < y2, the fluid is heated by the heating mechanism or cooled by the cooling mechanism. The heating amount per unit time until the fluid reaches y2 is

Equation

[0054] Let the state at y = y2 be state 2. In state 2, the fluid is a gas-liquid two-phase fluid, with temperature T2, pressure p2, specific enthalpy h of the gas phase V2 , specific enthalpy h of the liquid phase L2 , mass flow rate m of the gas phase V2 , mass flow rate m of the liquid phase L2 . For example, if the temperature T1 or pressure p2 is measured using a thermometer or pressure gauge, the specific enthalpies h of the gas phase and liquid phase V2 and the specific enthalpy h of the liquid phase L2 can still be obtained from physical property data and the like.

[0055] In the third embodiment, the aforementioned law of conservation of mass [Equation] still holds as it is. On the other hand, due to the presence of a heating mechanism or a cooling mechanism, the equation of the law of conservation of energy is as follows. [Equation] Therefore, the quadratic equation for calculating the mass flow rate m of the gas phase V2 is as follows. [Equation]

[0056] By following the same procedure as in the first embodiment, the theoretical solutions for the flow velocity u2 and quality x2 at y = y2 can be obtained.

[0057] Figure 2 shows the derivation and solution procedure of Equation (11).

[0058] Thus, according to this embodiment, the flow velocity and quality of the gas-liquid two-phase fluid in a pipe equipped with a heating mechanism or a cooling mechanism can be obtained.

[0059] [Example 1] FIG. 10 is a flowchart showing the processing procedure of Example 1. In this example, in the jet generating device as shown in FIG. 1, the flow velocity and quality of the gas-liquid two-phase jet ejected from the jet outlet are calculated.

[0060] In step S1, the mass flow rate and specific enthalpy of the liquid flowing into the jet outlet are obtained. The mass flow rate of the liquid may be detected by a flow meter or the like for the flowing liquid, or a constant flow rate may be determined as the specification of the device. Also, the specific enthalpy of the liquid can be obtained from a physical property value table such as a steam table if the temperature and pressure of the liquid are known. The temperature and pressure of the liquid may be detected by a thermometer or a pressure gauge, or may be determined in advance to be constant values. The physical property value table may be stored inside or outside the jet generating device as a database. At this time, the data stored in the database may be automatically read using a CPU or the like.

[0061] In step S2, the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase jet flowing out from the jet outlet are obtained. The specific volume and specific enthalpy of each of the gas phase and liquid phase at the jet outlet can be obtained from a physical property value table such as a saturation table. Here too, the physical property value table may be stored inside or outside the jet generating device as a database, and the data stored in the database may be automatically read using a CPU or the like.

[0062] In step S3, the mass flow rate of the gas phase of the gas-liquid two-phase jet at the jet outlet is calculated. The mass flow rate of the gas phase is based on the mass flow rate and specific enthalpy of the liquid flowing into the jet outlet obtained in step S1, and the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase jet flowing out from the jet outlet obtained in step S2. [Equation] is calculated using.

[0063] In step S4, the flow velocity and quality of the gas-liquid two-phase jet at the jet outlet are calculated. First [Number] is used to calculate the mass flow rate of the liquid phase of the gas-liquid two-phase jet at the jet outlet. Subsequently, the flow velocity is [Number] calculated using. Furthermore, the quality is [Number] calculated using.

[0064] According to this embodiment, in the jet generating device as shown in FIG. 1, the jet outlet flow velocity and quality that strictly satisfy the energy conservation equations of thermodynamics and fluid mechanics of the gas-liquid two-phase jet ejected from the jet outlet into which the liquid flows can be obtained.

[0065] The specific enthalpy of the liquid may be calculated from the initial temperature and initial pressure of the liquid. That is, the specific enthalpy of the liquid can be specifically calculated from the actually measured or predetermined initial temperature and initial pressure.

[0066] The flow path through which the liquid flows into the jet outlet may be insulated. In this way, the calculation can be simplified by using the model in which the flow path of the jet outlet is insulated. In this technology, since the obtained solution does not depend on the shape of the flow path, the results of this embodiment can be widely applied to various flow paths.

[0067] The flow at the cross-section of the jet outlet may be a uniform dispersion flow in which the liquid phase and the gas phase flow out at a uniform flow velocity. In this way, the calculation can be simplified by modeling the flow at the cross-section of the jet outlet to have a uniform flow velocity.

[0068] The gas-liquid two-phase jet may reach thermal equilibrium at the jet outlet and be in a saturated state. In this case, the pressure may be assumed to be equal to the ambient environmental pressure (e.g., atmospheric pressure). Therefore, in this case, the thermodynamic state of the jet outlet can be considered as a saturated state at the ambient environmental pressure. By modeling the state at the jet outlet in this way, the calculation can be simplified.

[0069] [Example 2] The method of Example 1 can be implemented as a computer program. That is, this program includes steps of obtaining the mass flow rate and specific enthalpy of the liquid (step S1), obtaining the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase jet (step S2), calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet at the jet outlet (step S3), and calculating the flow velocity and quality of the gas-liquid two-phase jet (step S4), and causing a computer to execute the method including these steps.

[0070] With this program, in a jet generation device as shown in FIG. 1, a method for obtaining the jet outlet flow velocity and quality that strictly satisfy the energy conservation equations of thermodynamics and fluid mechanics of the gas-liquid two-phase jet ejected from the jet outlet into which the liquid flows can be implemented as a computer program.

[0071] As an example, the flow velocity and quality obtained by executing this program can also be drawn as shown in FIGS. 3 and 4 and shown to the user.

[0072] [Example 3] FIG. 11 is a flowchart showing the processing procedure of Example 3. In this example, in a jet generation device including a gas supply mechanism, a liquid supply mechanism, and a two-fluid nozzle that combines gas and liquid to atomize the liquid as shown in FIG. 6, the flow velocity and quality of the gas-liquid two-phase jet ejected from the two-fluid nozzle are calculated.

[0073] In step S11, the mass flow rate and specific enthalpy of the liquid and gas flowing into the two-fluid nozzle are obtained.

[0074] In step S12, the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase fluid are obtained.

[0075] In step S13, the mass flow rate of the gas phase of the gas-liquid two-phase jet in the two-fluid nozzle is calculated. The mass flow rate of the gas phase is based on the mass flow rate and specific enthalpy of the liquid and gas flowing into the two-fluid nozzle obtained in step S11, and the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase fluid obtained in step S12. [Equation] It is calculated using.

[0076] In step S14, the flow velocity and quality of the gas-liquid two-phase jet in the two-fluid nozzle are calculated. First [Equation] Using, the mass flow rate of the liquid phase of the gas-liquid two-phase jet in the two-fluid nozzle is calculated. Subsequently, the flow velocity is [Equation] It is calculated using. Further, the quality is [Equation] It is calculated using.

[0077] According to this embodiment, in the jet generating device as shown in FIG. 6, the jet outlet flow velocity and quality that strictly satisfy the energy conservation equations of thermodynamics and fluid mechanics of the gas-liquid two-phase jet ejected from the two-fluid nozzle can be obtained.

[0078] [Embodiment 4] The method of Example 3 can be implemented as a computer program. That is, this program includes steps of obtaining the mass flow rates and specific enthalpies of the liquid and gas flowing into the two-fluid nozzle (step S11), obtaining the specific volumes and specific enthalpies of the gas phase and liquid phase of the gas-liquid two-phase jet (step S12), calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet in the two-fluid nozzle (step S13), and calculating the flow velocity and quality of the gas-liquid two-phase jet (step S14), and causes a computer to execute the method including these steps.

[0079] By this program, in a jet generating device as shown in FIG. 6, a method for obtaining the jet outlet flow velocity and quality that strictly satisfy the energy conservation equations of thermodynamics and fluid mechanics of the gas-liquid two-phase jet ejected from the two-fluid nozzle can be implemented as a computer program.

[0080] As an example, the flow velocity and quality obtained by executing this program can also be drawn as shown in FIGS. 7 and 8 and shown to the user.

[0081] [Example 5] FIG. 12 is a flowchart showing the processing procedure of Example 5. In this example, a heating mechanism or a cooling mechanism for heating the fluid as shown in FIG. 9 is provided, and in a pipe through which the fluid passes inside, the flow velocity and quality of the heated fluid are calculated.

[0082] In step S21, the mass flow rate and specific enthalpy of the fluid at the first position are obtained.

[0083] In step S22, the specific volumes and specific enthalpies of the gas phase and liquid phase of the gas-liquid two-phase fluid are obtained.

[0084] In step S23, the mass flow rate of the gas phase of the gas-liquid two-phase fluid at the second position is calculated. The mass flow rate of the gas phase is based on the mass flow rate and specific enthalpy of the fluid obtained in step S21, and the specific volumes and specific enthalpies of the gas phase and liquid phase of the gas-liquid two-phase fluid obtained in step S22, [Number] and is calculated using.

[0085] In step S24, the flow velocity and quality of the gas-liquid two-phase jet at the second position are calculated. First [Number] using, the mass flow rate of the liquid phase of the gas-liquid two-phase jet at the second position is calculated. Subsequently, the flow velocity is [Number] calculated using. Furthermore, the quality is [Number] calculated using.

[0086] According to this embodiment, in the pipe as shown in FIG. 9, the jet outlet flow velocity and quality that exactly satisfy the energy conservation equations of thermodynamics and fluid mechanics of the fluid at the second position can be obtained.

[0087] [Example 6] The method of Example 5 can be implemented as a computer program. That is, this program includes a step of obtaining the mass flow rate and specific enthalpy of the fluid at the first position (step S21), a step of obtaining the specific volumes and specific enthalpies of the gas phase and liquid phase of the gas-liquid two-phase fluid (step S22), and the gas-liquid two-phase step of calculating the mass flow rate of the gas phase of the fluid (step S23), and a step of calculating the flow velocity and quality of the gas-liquid two-phase jet (step S24), and causes the computer to execute the method including these steps.

[0088] With this program, in the piping as shown in FIG. 9, a method for obtaining the jet velocity and quality of the fluid at the second position that exactly satisfies the energy conservation equations of thermodynamics and fluid mechanics can be implemented as a computer program.

[0089] [Effect] The embodiments and examples described above have the following remarkable effects and advantages over the prior art. · It is possible to obtain an exact solution rather than an approximate solution for the flow velocity and quality. · The solution is independent of the flow path. · Complicated discretization and digitization are not required. · The calculation is simple, and the solution can be obtained in a short time with few computing resources.

[0090] [Aspects of the present disclosure] One aspect of the present disclosure is a method for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a jet orifice into which a liquid flows. This method includes steps of acquiring the mass flow rate and specific enthalpy of the liquid, acquiring the specific volume and specific enthalpy of each of the gas phase and the liquid phase of the gas-liquid two-phase jet, calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet at the jet orifice, and calculating the flow velocity and quality of the gas-liquid two-phase jet. The step of calculating the mass flow rate of the gas phase is [Equation] is used for the calculation. The steps of calculating the flow velocity and quality are [Equation] [Equation] [Equation] are used for the calculation. [Equation] represents the total mass flow rate of gas and liquid.

Number

Number

Number

[0091] According to this aspect, in the gas-liquid two-phase jet ejected from the nozzle into which the liquid flows, the nozzle exit velocity and quality that exactly satisfy the energy conservation equations of thermodynamics and fluid mechanics can be obtained.

[0092] In one aspect, the specific enthalpy of the liquid may be calculated from the initial temperature and initial pressure of the liquid.

[0093] According to this aspect, a method for specifically determining how to calculate the specific enthalpy of the liquid can be specified.

[0094] In one aspect, the flow path through which the liquid flows into the ejection port is insulated.

[0095] According to this aspect, the calculation can be simplified by using a model in which the flow path of the ejection port is insulated.

[0096] In one aspect, the flow in the cross-section of the ejection port is a uniform dispersion flow in which the liquid phase and the gas phase flow out at a uniform flow velocity.

[0097] According to this aspect, the calculation can be simplified by modeling the flow in the cross-section of the ejection port to a uniform flow velocity.

[0098] In one aspect, the state at the ejection port is a gas-liquid two-phase state due to flashing.

[0099] According to this aspect, the calculation can be simplified by modeling the state at the ejection port.

[0100] Yet another aspect of the present disclosure is also a method. This method is a method for calculating the flow velocity and quality of a fluid passing through a pipe provided with a heating mechanism or a cooling mechanism between a first position and a second position downstream of the first position. The fluid is liquid at the first position and a gas-liquid two-phase fluid at the second position. This method includes the steps of obtaining the mass flow rate and specific enthalpy of the fluid at the first position, obtaining the specific volume and specific enthalpy of each of the gas phase and the liquid phase of the gas-liquid two-phase fluid, calculating the mass flow rate of the gas phase of the gas-liquid two-phase fluid at the second position, and calculating the flow velocity and quality of the gas-liquid two-phase fluid. The step of calculating the mass flow rate of the gas phase is

Equation

Equation

Equation

Number

Number

Number

Number

Number

[0101] According to this aspect, in the fluid passing through the pipe equipped with the heating mechanism or the cooling mechanism, it is possible to obtain the jet outlet flow velocity and quality that exactly satisfy the energy conservation equations of thermodynamics and fluid mechanics.

[0102] Yet another aspect of the present disclosure is also a method. This method is a method for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a two-fluid nozzle of a jet generating device including a gas supply mechanism, a liquid supply mechanism, and a two-fluid nozzle that combines a gas and a liquid to atomize the liquid. This method includes steps of obtaining the mass flow rate and specific enthalpy of the liquid and gas flowing into the two-fluid nozzle, obtaining the specific volume and specific enthalpy of each of the gas phase and the liquid phase of the gas-liquid two-phase jet, calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet in the two-fluid nozzle, and calculating the flow velocity and quality of the gas-liquid two-phase jet. The step of calculating the mass flow rate of the gas phase is

Number

Number

Number

Number

Number

Number

Number

[0103] According to this aspect, in the gas-liquid two-phase jet ejected from a two-fluid nozzle that combines gas and liquid to atomize the liquid, it is possible to obtain the jet outlet velocity and quality that exactly satisfy the energy conservation equations of thermodynamics and fluid mechanics.

[0104] Still another aspect of the present disclosure is a program for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a jet outlet into which a liquid flows. This program causes a computer to execute a method including steps of acquiring the mass flow rate and specific enthalpy of the liquid, acquiring the specific volume and specific enthalpy of each of the gas phase and the liquid phase of the gas-liquid two-phase jet, calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet at the jet outlet, and calculating the flow velocity and quality of the gas-liquid two-phase jet. The step of calculating the mass flow rate of the gas phase is

Equation

Equation

Equation

Equation

[0105] According to this aspect, in the gas-liquid two-phase jet ejected from the jet outlet into which the liquid flows, a method for obtaining the jet outlet flow velocity and quality that strictly satisfy the energy conservation equations of thermodynamics and fluid mechanics can be implemented as a computer program.

[0106] Yet another aspect of the present disclosure is also a program. This program is a program for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a two-fluid nozzle of a jet generator including a gas supply mechanism, a liquid supply mechanism, and a two-fluid nozzle that combines gas and liquid to atomize the liquid. This program causes a computer to execute a method including: a step of acquiring the mass flow rate and specific enthalpy of the liquid and gas flowing into the two-fluid nozzle; a step of acquiring the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase jet; a step of calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet in the two-fluid nozzle; and a step of calculating the flow velocity and quality of the gas-liquid two-phase jet. The step of calculating the mass flow rate of the gas phase is

Number

Number

Number

Number

Number

Number

Number

[0107] According to this aspect, in a gas-liquid two-phase jet ejected from a two-fluid nozzle that combines a gas and a liquid to atomize the liquid, a method for obtaining the jet outlet flow velocity and quality that exactly satisfies the energy conservation equations of thermodynamics and fluid mechanics can be implemented as a computer program.

[0108] Yet another aspect of the present disclosure is also a program. This program is a program for calculating the flow velocity and quality of a fluid passing through a pipe provided with a heating mechanism or a cooling mechanism between a first position and a second position downstream of the first position. The fluid is a liquid at the first position and a gas-liquid two-phase fluid at the second position. This program causes a computer to execute a method including steps of obtaining the mass flow rate and specific enthalpy of the fluid at the first position, obtaining the specific volume and specific enthalpy of each of the gas phase and the liquid phase of the gas-liquid two-phase fluid, calculating the mass flow rate of the gas phase of the gas-liquid two-phase fluid at the second position, and calculating the flow velocity and quality of the gas-liquid two-phase fluid. The step of calculating the mass flow rate of the gas phase is

Equation

Equation

[0109] According to this aspect, a method for obtaining an outlet flow velocity and a quality that exactly satisfy the energy conservation equations of thermodynamics and fluid mechanics in a fluid passing through a pipe equipped with a heating mechanism or a cooling mechanism can be implemented as a computer program.

[0110] As described above, the present disclosure has been described based on examples. These examples are illustrative, and it is understood by those skilled in the art that various modifications are possible for each component and the combination of each processing process, and such modifications are also within the scope of the present disclosure.

[0111] [Modification Example 1] The jet generation device described in the above example can be applied to, for example, an outlet in fuel injection into an internal combustion engine accompanied by depressurization boiling. At this time, since the flow velocity and quality at the outlet can be calculated by the present technology, this can be fed back to a fuel control device, a power control device, etc., to realize more efficient engine control.

[0112] [Modification Example 2] The method for calculating the flow velocity and quality described in the above example can be applied to, for example, an outlet of a high-temperature high-pressure water pipe or liquefied hydrogen. At this time, since the flow velocity and quality at the outlet can be calculated by the present technology, this can be fed back to a safety device, etc., to realize more secure leakage accident countermeasures.

[0113] In understanding the technical idea abstracted from the embodiments and modification examples, the technical idea should not be construed as being limited to the contents of the embodiments and modification examples. The above-described embodiments and modification examples are merely specific examples, and many design changes such as changes, additions, deletions, etc. of components are possible. In the embodiments, regarding the content where such design changes are possible, the notation "Embodiment" is attached for emphasis. However, design changes are also permitted for the content that is not denoted as such. [Industrial Applicability]

[0114] The present disclosure is particularly useful for applications in the following fields. However, it is not limited thereto, and it can be widely applied especially in the fields of "artificially generating a flow accompanied by evaporation and condensation, actively controlling it, and applying it industrially" and "taking passive safety measures against a pressure-reducing boiling jet that occurs spontaneously unintentionally". · Understanding and controlling the nozzle exit conditions in fuel injection into an internal combustion engine accompanied by pressure-reducing boiling · Understanding and controlling the pressure-reducing boiling that occurs when fuel is taken out from a liquid rocket fuel tank · Evaluating and optimally designing nozzle internal cavitation and pressure-reducing boiling of a refrigerant that occurs in a small heat pipe or an expansion valve of a refrigeration cycle · Application of the thermodynamic self-suppression effect of cavitation · Safety evaluation and countermeasures for a pressure-reducing boiling jet that occurs during a leakage accident from a high-temperature and high-pressure water pipe · Countermeasures against leakage accidents accompanied by pressure-reducing boiling and evaporation of liquefied hydrogen · Optimal design of a cleaning device using a water-steam mixed jet

Explanation of reference numerals

[0115] 1 ··· Jet generation device. 2 ··· Jet generation device. 11 ··· Pipe. S1 ··· Step of obtaining the mass flow rate and specific enthalpy of a liquid. S2 ··· Step of obtaining the specific volume and specific enthalpy of each of the gas phase and liquid phase of a gas-liquid two-phase jet. S3 ··· Step of calculating the mass flow rate of the gas phase of a gas-liquid two-phase jet at the nozzle exit. S4 ··· Step of calculating the flow velocity and quality of a gas-liquid two-phase jet. S21 ··· Step of obtaining the mass flow rate and specific enthalpy of a liquid and a gas flowing into a two-fluid nozzle. S12 ··· Step of obtaining the specific volume and specific enthalpy of each of the gas phase and liquid phase of a gas-liquid two-phase jet. S13 ··· Step of calculating the mass flow rate of the gas phase of a gas-liquid two-phase jet in a two-fluid nozzle. S14 ··· Step of calculating the flow velocity and quality of a gas-liquid two-phase jet. S21 ··· A step of obtaining the mass flow rate and specific enthalpy of the fluid at the first position. S22 ··· A step of obtaining the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase fluid. S23 ··· A step of calculating the mass flow rate of the gas phase of the gas-liquid two-phase fluid at the second position. S24 ··· A step of calculating the flow velocity and quality of the gas-liquid two-phase jet.

Claims

1. A method for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a jet outlet into which a liquid flows, comprising: obtaining the mass flow rate and specific enthalpy of the liquid; obtaining the specific volume and specific enthalpy of each of the gas phase and the liquid phase of the gas-liquid two-phase jet; calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet at the jet outlet; calculating the flow velocity and quality of the gas-liquid two-phase jet; wherein the step of calculating the mass flow rate of the gas phase is performed using 【Number 16】 and the step of calculating the flow velocity and quality is performed using 【Number 3】 【Number 7】 【Number 9】 where 【Number 1】 represents the total mass flow rate of the gas and the liquid, [Number 4] represents the mass flow rate of the gas phase of the gas-liquid two-phase jet at the jet outlet, 【Number 5】 represents the mass flow rate of the liquid phase of the gas-liquid two-phase jet at the jet outlet, 【Number 14】 is the heating amount per unit time from the outside, indicating that the fluid is heated from the outside when positive and cooled from the outside when negative, h １ represents the specific enthalpy of the liquid upstream of the nozzle outlet, ν Ｖ２ represents the specific volume of the gas phase at the jet outlet, ν Ｌ２ represents the specific volume of the liquid phase at the nozzle outlet, h Ｖ２ represents the specific enthalpy of the gas phase at the nozzle outlet, h Ｌ２ represents the specific enthalpy of the liquid phase at the nozzle outlet, A represents the opening area of the jet outlet. u ２ represents the flow velocity at the nozzle exit, x ２ is a method characterized by representing the quality at the nozzle outlet.

2. The method according to claim 1, wherein the mass flow rate and specific enthalpy of the liquid are calculated from the initial temperature and initial pressure of the liquid.

3. The method according to claim 1, wherein the flow path through which the liquid flows into the jet outlet is insulated.

4. The method according to claim 1, wherein the flow in the cross section of the jet outlet is a uniform dispersion flow in which the liquid phase and the gas phase flow out at a uniform flow velocity.

5. The method according to claim 1, wherein the state at the jet outlet is a gas-liquid mixed phase state due to depressurization boiling.

6. A method for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a two-fluid nozzle of a jet generator including a gas supply mechanism, a liquid supply mechanism, and a two-fluid nozzle that combines a gas and a liquid to atomize the liquid, comprising: obtaining the mass flow rate and specific enthalpy of the liquid and the gas flowing into the two-fluid nozzle; obtaining the specific volume and specific enthalpy of each of the gas phase and the liquid phase of the gas-liquid two-phase jet; calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet at the two-fluid nozzle; calculating the flow velocity and quality of the gas-liquid two-phase jet; wherein the step of calculating the mass flow rate of the gas phase is performed using 【Number 13】 and the step of calculating the flow velocity and quality is performed using 【Number 11】 【Number 7】 【Number 9】 ​ 【Number 1】 represents the total mass flow rate of the gas and the liquid, 【Number 4】 represents the mass flow rate of the gas phase of the gas-liquid two-phase jet in the two-fluid nozzle, 【Number 5】 represents the mass flow rate of the liquid phase of the gas-liquid two-phase jet in the two-fluid nozzle, h １ represents the specific enthalpy of the liquid upstream of the two-fluid nozzle, ν Ｖ２ represents the specific volume of the gas phase in the two-fluid nozzle, ν Ｌ２ represents the specific volume of the liquid phase in the two-fluid nozzle, h Ｖ２ represents the specific enthalpy of the gas phase in the two-fluid nozzle, h Ｌ２ represents the specific enthalpy of the liquid phase in the two-fluid nozzle, A represents the opening area of the two-fluid nozzle, u ２ represents the flow velocity in the two-fluid nozzle, x ２ is a method characterized by representing the quality in the two-fluid nozzle.

7. A method for calculating the flow velocity and quality of a fluid passing through a pipe provided with a heating mechanism or a cooling mechanism between a first position and a second position downstream of the first position, wherein the fluid is liquid at the first position and a gas-liquid two-phase fluid at the second position, obtaining the mass flow rate and specific enthalpy of the fluid at the first position; obtaining the specific volume and specific enthalpy of each of the gas phase and the liquid phase of the gas-liquid two-phase fluid; calculating the mass flow rate of the gas phase of the gas-liquid two-phase fluid at the second position; calculating the flow velocity and quality of the gas-liquid two-phase fluid; including, the step of calculating the mass flow rate of the gas phase is 【Number 16】 performed using, the step of calculating the flow velocity and quality is 【Number 3】 【Number 7】 【Number 9】 performed using, 【Number 1】 represents the mass flow rate of the fluid at the first position, 【Number 4】 represents the mass flow rate of the gas phase of the gas-liquid two-phase fluid at the second position, 【Number 5】 represents the mass flow rate of the liquid phase of the gas-liquid two-phase fluid at the second position, 【Number 14】 is the heating amount per unit time from the outside, indicating that the fluid is heated from the outside when positive and cooled from the outside when negative, h1 represents the specific enthalpy of the fluid at the first position, ν Ｖ２ represents the specific volume of the gas phase at the second position, ν Ｌ２ represents the specific volume of the liquid phase at the second position, h Ｖ２ represents the specific enthalpy of the gas phase at the second position, h Ｌ２ represents the specific enthalpy of the liquid phase at the second position, A represents the cross-sectional area of the second position, u ２ represents the flow velocity at the second position, x ２ is a method characterized by representing the quality at the second position.

8. A program for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a jet outlet into which a liquid flows, obtaining the mass flow rate and specific enthalpy of the liquid; obtaining the specific volume and specific enthalpy of each of the gas phase and the liquid phase of the gas-liquid two-phase jet; calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet at the jet outlet; calculating the flow velocity and quality of the gas-liquid two-phase jet; including, the step of calculating the mass flow rate of the gas phase is 【Number 16】 performed using, the step of calculating the flow velocity and quality is [Number 3] 【Number 7】 【Number 9】 performed using, 【Number 1】 represents the total mass flow rate of the gas and the liquid, [Number 4] represents the mass flow rate of the gas phase of the gas-liquid two-phase jet at the jet outlet, 【Number 5】 represents the mass flow rate of the liquid phase of the gas-liquid two-phase jet at the jet outlet, 【Number 14】 is the heating amount per unit time from the outside. When it is positive, it means the fluid is heated from the outside, and when it is negative, it means the fluid is cooled from the outside. h １ represents the specific enthalpy of the liquid upstream of the nozzle outlet, ν Ｖ２ represents the specific volume of the gas phase at the nozzle outlet, ν Ｌ２ represents the specific volume of the liquid phase at the nozzle outlet, h Ｖ２ represents the specific enthalpy of the gas phase at the nozzle exit, h Ｌ２ represents the specific enthalpy of the liquid phase at the nozzle outlet, A represents the opening area of the ejection port. u ２ represents the flow velocity at the jet outlet, x ２ A program that causes a computer to execute a method characterized by representing the quality at the nozzle exit.

9. A program for calculating the flow velocity and quality of a gas-liquid two-phase jet ejected from a two-fluid nozzle of a jet generator including a gas supply mechanism, a liquid supply mechanism, and a two-fluid nozzle that combines gas and liquid to atomize the liquid, The step of obtaining the mass flow rate and specific enthalpy of the liquid and gas flowing into the two-fluid nozzle, The step of obtaining the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase jet, The step of calculating the mass flow rate of the gas phase of the gas-liquid two-phase jet in the two-fluid nozzle, The step of calculating the flow velocity and quality of the gas-liquid two-phase jet, including, The step of calculating the mass flow rate of the gas phase, 【Number 13】 performs the calculation using, The step of calculating the flow velocity and quality, 【Number 11】 【Number 7】 【Number 9】 performs the calculation using, 【Number 1】 represents the total mass flow rate of the gas and liquid, 【Number 4】 represents the mass flow rate of the gas phase of the gas-liquid two-phase jet in the two-fluid nozzle, 【Number 5】 represents the mass flow rate of the liquid phase of the gas-liquid two-phase jet in the two-fluid nozzle, h １ represents the specific enthalpy of the liquid upstream of the two-fluid nozzle, ν Ｖ２ represents the specific volume of the gas phase in the two-fluid nozzle, ν Ｌ２ represents the specific volume of the liquid phase in the two-fluid nozzle, h Ｖ２ represents the specific enthalpy of the gas phase in the two-fluid nozzle, h Ｌ２ represents the specific enthalpy of the liquid phase in the two-fluid nozzle, A represents the opening area of the two-fluid nozzle. u ２ represents the flow velocity in the two-fluid nozzle, x ２ A program that causes a computer to execute a method characterized by representing the quality in the two-fluid nozzle.

10. A program for calculating the flow velocity and quality of a fluid passing through a pipe provided with a heating mechanism or a cooling mechanism between a first position and a second position downstream of the first position, The fluid is a liquid at the first position and a gas-liquid two-phase fluid at the second position, The step of obtaining the mass flow rate and specific enthalpy of the fluid at the first position, The step of obtaining the specific volume and specific enthalpy of each of the gas phase and liquid phase of the gas-liquid two-phase fluid, The step of calculating the mass flow rate of the gas phase of the gas-liquid two-phase fluid at the second position, The step of calculating the flow velocity and quality of the gas-liquid two-phase fluid, including, The step of calculating the mass flow rate of the gas phase, 【Number 16】 performs the calculation using, The step of calculating the flow velocity and quality, 【Number 3】 【Number 7】 【Number 9】 performs the calculation using, 【Number 1】 represents the mass flow rate of the fluid at the first position, 【Number 4】 represents the mass flow rate of the gas phase of the gas-liquid two-phase fluid at the second position, 【Number 5】 represents the mass flow rate of the liquid phase of the gas-liquid two-phase fluid at the second position, 【Number 14】 is the heating amount per unit time from the outside. When it is positive, it means that the fluid is heated from the outside, and when it is negative, it means that the fluid is cooled from the outside. h1 represents the specific enthalpy of the fluid at the first position. ν Ｖ２ represents the specific volume of the gas phase at the second position, ν Ｌ２ represents the specific volume of the liquid phase at the second position, h Ｖ２ represents the specific enthalpy of the gas phase at the second position, h Ｌ２ represents the specific enthalpy of the liquid phase at the second position, A represents the cross-sectional area of the second position. u ２ represents the flow velocity at the second position, x ２ A program that causes a computer to execute a method characterized by representing the quality at the second position.

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