JPH11101530A - Refrigerant distributor and refrigerating cycle apparatus using refrigerant distributor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a refrigerant distributor capable of sufficiently stirring, mixing, and uniformly distributing a refrigerant even when the refrigerant flows in irrespective of installation conditions of the refrigerant distributor, and improve performance, efficiency, and reliability of a refrigerating apparatus using the refrigerant distributor. SOLUTION: When a refrigerant flowing in from an inflow pipe is distributed to a plurality of outflow pipes 3 after passage through a mixing section 4 and a branch space 5, the mixing section 4 is constructed with a thin pipe to ensure a uniform flow. When an inner diameter of the mixing section 4 is assumed D [m], length L [ml in a flow direction, height [m] of the branch space 5 in the flow direction, a volume V [m<3> ], and a mass flow rate W [kg/s] of the refrigerant flowing through the mixing section 4, L/D>5, W/(π×D<2> /4)>500 is satisfied to bring a flow of a gas/liquid two phase refrigerant in the mixing section 4 into a uniform flow. Further, W/H>2, W/V>10 is satisfied, whereby the refrigerant is uniformly distributed from the branch space 5 to the outflow pipe 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a refrigerant distributor used for a refrigeration cycle device such as an air conditioner and a refrigeration device.

[0002]

2. Description of the Related Art In a heat exchanger acting as a condenser or an evaporator of a refrigeration cycle device such as an air conditioner or a refrigeration device, when an internal refrigerant flow path is divided into a plurality of paths,
At the inlet of the heat exchanger, a refrigerant distributor for distributing the refrigerant to each path is required. Further, for example, in a multi-type air conditioner in which a plurality of outdoor units and indoor units are connected in parallel, a refrigerant distributor is required to distribute the refrigerant from the main refrigerant flow path to each unit. Generally, the refrigerant that has passed through the expansion valve of the refrigeration cycle device and the refrigerant at the evaporator inlet are in a gas-liquid two-phase state of a gas refrigerant and a liquid refrigerant, and a density distribution is generated in a cross section of the refrigerant flowing in the piping. . For example, due to the effect of centrifugal force when the inflow pipe has a bend, and due to the influence of gravity when the inflow pipe and the refrigerant distributor body are arranged horizontally, the liquid refrigerant flows unevenly to one pipe inner surface. A phenomenon occurs. Therefore, the refrigerant distributor can prevent gas-liquid separation without causing the above-described drift phenomenon, uniformly mix the refrigerant, and determine the gas-liquid mass flow ratio at the refrigerant distributor inlet and the refrigerant distributor. A function of distributing the refrigerant in a state where the gas-liquid mass flow ratio at the outlet is equal is required.

A conventional refrigerant distributor is disclosed in Japanese Patent Laid-Open Publication No. 2-16.
No. 6366. FIG. 15 is a sectional view showing the refrigerant distributor. In the figure, 13 is a refrigerant distributor main body, 15 is a throttle section, 16 is an inflow pipe, 17 is a collision wall, 18
Is a peripheral wall, 19 is an inlet of the outflow pipe 21, 20 is an outflow pipe 21
Is an outflow pipe. Conventional refrigerant distributors
The inflow pipe 16 and the plurality of outflow pipes 21 are respectively connected to the refrigerant distributor main body 13, and a branch space including the collision wall 17 and the peripheral wall 18 is formed inside the refrigerant distributor main body 13, and the branch space is formed from the inflow pipe 16 to the branch space. A throttle section 15 is provided in a flow path leading to the passage. When the inlet pipe diameter is D1, the inner diameter of the peripheral wall is D2, the throttle diameter is L1, and the distance from the throttle unit 15 to the collision wall 17 is L2, D2 / D1 <2.0, L1 / D1 <0.5,
L2 <30 mm.

In the refrigerant distributor configured as described above, the refrigerant flowing from the inflow pipe 16 is jetted into the branch space by the throttle portion 15 and collides with the collision wall 17 of the branch space to make the gas-liquid two-phase flow uniform. Promote. Then, the water is distributed from the branch space to the plurality of outflow pipes 21. By making the branch space small to some extent, the formation of liquid pools and air pockets is eliminated, and the distribution is uniformly distributed to the outflow pipes 21. .

[0005]

Since the conventional refrigerant distributor is configured as described above, the pipe may be bent upstream of the inflow pipe 16 or the inflow pipe 16 or the refrigerant distributor main body 13 may be horizontal. When the gas-liquid two-phase refrigerant has a deviated flow due to, for example, the arrangement of the refrigerant, even if the throttle diameter L1 is set to L1 / D1 <0.5 with respect to the inflow pipe diameter D1, the plurality of outflow pipes 21 are evenly distributed. Cannot be distributed. This is because, under the above conditions alone, when the flow rate of the refrigerant is low, or when the mass flow rate of the liquid refrigerant is extremely large due to the change in the gas-liquid two-phase flow rate of the refrigerant, the gas-liquid two-phase refrigerant This is because they cannot be uniformly stirred and mixed. Further, the collision wall 17 and the peripheral wall 18
The volume of the branch space of the ^{π × (D2) 2/4} × L2
(Π: pi), but D2 / D1 <2.
If only 0, L2 <30 mm, the branch space volume cannot be said to be sufficiently small when the flow rate of the refrigerant is low, and the gas-liquid two-phase refrigerant is separated again after passing through the throttle unit 15, and the refrigerant flows through the outlet pipe 21. There was a problem that equal distribution was not possible.

The refrigerant distributor according to the present invention has been made in order to solve the above-mentioned problems, and has a problem in that the piping upstream of the refrigerant distributor has a bend or that the piping and the refrigerant distributor main body are horizontal. In any situation where a refrigerant distributor is installed, such as when the refrigerant is installed, the refrigerant is agitated and mixed without being affected by the drift, without causing gas-liquid separation, and is homogenized in a plurality of outlet pipes. The purpose is to distribute the refrigerant.

Further, by using the refrigerant distributor according to the present invention in a refrigeration cycle device such as an air conditioner or a refrigeration device, the performance and efficiency thereof are improved, and reliability problems due to non-uniform refrigerant distribution are caused. For example, an object of the present invention is to prevent generation of a refrigerant noise and dew drop in an evaporator.

[0008]

According to a first aspect of the present invention, there is provided a refrigerant distributor connected to a mixing section through which a refrigerant flowing from an inflow pipe passes, and a plurality of outflow pipes to discharge the refrigerant flowing from the mixing section. With a branch space to distribute to each of the pipes,
The mixing section is reduced in diameter to an inner diameter smaller than the pipe diameter of the inflow pipe so that the flow state becomes a bubble flow or an annular spray flow by compressing and accelerating the refrigerant,
In addition, it is formed of a thin tube having an inner diameter much smaller than the length in the flow direction.

A refrigerant distributor according to a second aspect of the present invention is connected to a mixing section through which the refrigerant flowing from the inflow pipe passes and a plurality of outflow pipes, and transfers the refrigerant flowing from the mixing section to each of the outflow pipes. It has a branch space for distribution, and is configured so that the flow state of the refrigerant in the mixing section satisfies the following equation. Gg / λ> 5 × 10 ⁴ and λ × ψ × Gl / Gg> 20 where λ = [(ρg / ρa) × (ρl / ρw)] ^1/2 ψ = (σw / σ) × [(μl / μw) × (ρw / ρl)
² ] ^1/3 Gg [kg / m ² · h]: Mass flow rate of gas refrigerant Gl [kg / m ² · h]: Mass flow rate of liquid refrigerant ρ: Density σ: Surface tension μ: Viscosity coefficient Subscript g, l , A, and w represent gas, liquid, air, and water, respectively.

The refrigerant distributor according to claim 3 of the present invention is the refrigerant distributor according to claim 1, wherein the inside diameter of the mixing section is D [m] and the length of the refrigerant in the flow direction is L [m]. Then, the mixing unit is configured so that D and L satisfy L / D> 5.

The refrigerant distributor according to claim 4 of the present invention is the refrigerant distributor according to claim 2, wherein the inner diameter of the mixing section is D [m], and the mass flow rate of the refrigerant flowing through the mixing section is W [kg].
When / s] to, D, W ^{is, W / (π × D 2} /4)> 5
The mixing unit is configured to satisfy 00 (π: pi).

According to a fifth aspect of the present invention, in the refrigerant distributor according to any one of the first to fourth aspects, the height of the branch space in the flow direction of the refrigerant is H [ m], and the mass flow rate of the refrigerant flowing through the mixing section is W [kg /
s], the branch space is configured to satisfy W / H> 2.

According to a sixth aspect of the present invention, there is provided a refrigerant distributor according to any one of the first to fifth aspects, wherein the volume of the branch space is V [m ³ ], If the mass flow rate of the refrigerant flowing through is represented by W [kg / s],
The branch space is configured to satisfy W / V> 10.

A refrigerant distributor according to a seventh aspect of the present invention is the refrigerant distributor according to any one of the first to sixth aspects, wherein the refrigerant flows through at least one of the mixing section and the branch space. Is provided with a stirring means.

In a refrigeration cycle apparatus according to an eighth aspect of the present invention, the refrigerant distributor according to any one of the first to seventh aspects is provided at a refrigerant branch of a refrigerant flow path for circulating a refrigerant. It is a thing.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. Hereinafter, Embodiment 1 of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view showing a refrigerant distributor according to the first embodiment. In FIG. 1, 1 is a refrigerant distributor main body, 2 is an inflow pipe, 3a and 3b are, for example, two outflow pipes,
Is a mixing section composed of a thin tube, and 5 is a branch space. Also,
The arrow in the figure indicates the flow direction of the refrigerant, L is the length [m] of the mixing section 4 in the flow direction, D is the inner diameter [m] of the mixing section 4, and H is the height of the branch space 5 in the flow direction [ m] and V represent the volume [m ³ ] of the branch space 5, and W represents the mass flow rate [kg / s] of the refrigerant flowing through the mixing section 4.

The refrigerant distributor body 1 has an inflow pipe 2 at one end.
A plurality of, for example, two outflow pipes 3a, 3b are connected to the other end side, respectively, and a mixing section 4 is connected to the inflow pipe 2 on the inflow pipe 2 side of the refrigerant distributor body 1. The mixing section 4 is formed of a thin tube, and has a function of changing the flowing state of the flowing gas-liquid two-phase refrigerant into a homogeneous flow such as a bubble flow or an annular spray flow. In the present embodiment, for example, the inside diameter of the mixing section 4 is smaller than the inside diameter of the inflow pipe 2 and is significantly smaller than the length of the mixing section 4 in the flow direction. A branch space 5 is provided between the mixing section 4 and the two outflow pipes 3a and 3b. The refrigerant flowing from the inflow pipe 2 is accelerated by the contraction in the mixing section 4 and flows out through the branch space 5. It is distributed to the tubes 3a, 3b.

Next, the operation of the distribution will be described. FIG. 2 is an explanatory view showing the state of the refrigerant in the refrigerant distributor main body 1 installed horizontally, in which a gas-liquid two-phase refrigerant of a gas refrigerant and a liquid refrigerant flows in from an inflow pipe 2 and gas-liquid refrigerant flows out of outflow pipes 3a and 3b. 4 shows how a two-phase refrigerant flows out. FIG. 3 is a perspective view showing an example in which the outflow pipes 3a and 3b are installed in a horizontal direction. FIG. 4 is a view in which the arrangement of the outflow pipes 3a and 3b is rotated about the axis from that shown in FIG. FIG. 3 is a perspective view showing an example of installation in a vertical direction.
As shown in FIG. 2, in the inflow pipe 2, the liquid refrigerant is unevenly distributed on the lower surface of the pipe under the influence of gravity, and a drift phenomenon occurs. In the present embodiment, the inner diameter D of the mixing section 4 composed of a thin tube is
[M], length L [m], mass flow rate of refrigerant W [kg / s]
Is such that Expressions 1 and 2 are satisfied.

L / D> 5. . . (1) W / (π × D 2/4)> 500. . . (2) π: Pi

If the mixing section 4 is configured as described above, even when the gas-liquid two-phase refrigerant has a deviated flow including, for example, a case where the pipe upstream of the inflow pipe 2 is bent, the inflow from the inflow pipe 2 is performed. The gas-liquid two-phase refrigerant is contracted and accelerated in the mixing section 4, so that the gas-liquid two-phase refrigerant is sufficiently stirred and mixed to become a homogeneous flow.

In this embodiment, the relationship between the height H [m] and the volume V [m ³ ] of the branch space 5 satisfies the equations (3) and (4).

W / H> 2. . . (3) W / V> 10. . . (4)

In particular, when the outflow pipes 3a and 3b are installed vertically as shown in FIG. 4, the liquid refrigerant tends to be unevenly distributed in the lower outflow pipe 3a under the influence of gravity. When the height H [m] and the volume V [m ³ ] of the branch space 5 are determined, the gas-liquid two-phase refrigerant is sufficiently stirred and mixed in the branch space 5 to become a homogeneous flow, and the refrigerant flows out of the outlet pipes 3a and 3b. A homogeneous refrigerant flows out. For example, even if the cross-sectional area of the branch space 5 is larger than that of the mixing section 4, the volume V and the height H can be calculated by the formulas 3 and 3.
If the size is made small so as to satisfy the relationship of Expression 4, the gas-liquid two-phase refrigerant can be uniformly distributed to the outflow pipes 3a and 3b without forming a liquid pool or an air pocket. Here, the homogeneous state means that the gas-liquid mass flow ratio flowing through the inlet of the refrigerant distributor, that is, the inflow pipe 2, and the plurality of outlets of the refrigerant distributor, that is, the outflow pipe 3
This refers to a state in which the gas-liquid mass flow ratios flowing through a and 3b are equal.

Next, the inner diameter D [m] and the length L [m] of the mixing section 4 of the refrigerant distributor according to the present embodiment, the mass flow rate W [kg / s] of the refrigerant flowing through the mixing section 4, the branch space 5 height H
[M] and the volume V [m ³ ] to change the refrigerant distributor body 1
5, 6, 7, and 8 are graphs showing test results of the distribution ratio to the outflow pipes 3 a and 3 b in the case where the installation state is changed. This test is an example in which a refrigerant distributor having two outflow pipes 3a and 3b is installed horizontally and the outflow pipes 3a and 3b are arranged vertically as shown in FIG. The case where the drift of the liquid two-phase refrigerant is the largest is shown. The distribution ratio [%], which is the vertical axis in each drawing, indicates the refrigerant distribution ratio of the lower outflow pipe 3a of the two outflow pipes 3a and 3b. In each of the figures, the allowable range of the distribution ratio [%] of the practical outflow pipe 3a that does not cause performance degradation is set to 48% to 52%.

The horizontal axis in FIG. 5 is a parameter L / D (mixing unit 4).
The vertical axis represents the mass flow rate W = 0.01.
The distribution ratio [%] when [kg / s] is set is shown.
As shown in the figure, the allowable range is in the range of L / D> 5. In this range, the length L is configured to be sufficiently long with respect to the inner diameter D of the mixing section 4, so that the gas-liquid two-phase refrigerant is more Homogenized. The horizontal axis parameter ^{W / (π × D 2/} 4) in FIG. 6
(Mass flow per unit area in cross section of mixing section 4)
The vertical axis indicates the distribution ratio [%] when the length L of the mixing unit 4 is 0.05 [m] and the inner diameter D is 0.005 [m]. As shown in ^{FIG., W / (π × D 2} /4)
In the range of> 500, the permissible range is reached. In this range, the mass flow rate of the mixing section 4 is sufficiently high, so that the gas-liquid two-phase refrigerant is further homogenized. The horizontal axis in FIG. 7 is the parameter W / H (mass flow rate / height of the branch space 5), and the vertical axis is the mass flow rate W
= 0.01 [kg / s], length L of mixing section 4 = 0.05
[M] and the distribution ratio [%] when the inner diameter D is 0.005 [m]. As shown, W / H> 2
In this range, the height of the branch space 5 is made sufficiently small, so that the gas-liquid two-phase refrigerant is further homogenized. The horizontal axis in FIG. 8 is the parameter W / V (mass flow rate /
The vertical axis represents the mass flow rate W = 0.0.
1 [kg / s], length L of mixing section 4 = 0.05 [m],
The distribution ratio [%] when the inner diameter D is 0.005 [m] is shown. As shown in the figure, the allowable range is W / V> 10. In this range, since the volume of the branch space 5 is sufficiently small, the gas-liquid two-phase refrigerant is further homogenized.

As described above, if the mixing section 4 constituting the refrigerant distributor is formed of a thin tube, the gas-liquid two-phase refrigerant which has been deflected in the inflow pipe 2 is compressed and accelerated so as to have a uniform flow. Can be. In particular, if the shape of the mixing section 4 is configured to satisfy Expressions 1 and 2, the refrigerant can be reliably stirred and mixed.
Furthermore, if the shape of the branch space 5 is configured so as to satisfy the equations (3) and (4), the gas-liquid two-phase refrigerant in a homogeneous state flows out of the outflow pipes 3a and 3b, and the performance as a refrigerant distributor is maintained. it can.

Although FIGS. 3 and 4 show an example having two outflow pipes 3a and 3b, the same effect can be obtained when three or more outflow pipes are used. Further, the shape of the branch space 5 may be any shape such as a cylindrical shape or a saddle shape, and the height H is configured so as to satisfy Expression 3, and the volume V is configured so as to satisfy Expression 4. I just need. Further, even if neither Formula 3 nor Formula 4 are satisfied, if either the height H or the volume V is satisfied, the effect of uniformly distributing the gas-liquid two-phase refrigerant is exhibited to some extent.

In the above description, the gas-liquid two-phase refrigerant flows into the refrigerant distributor. However, the gas-liquid single-phase refrigerant, the gas-liquid two-phase refrigerant that flows by mixing the gas refrigerant and the refrigerating machine oil, and the like are described. The same applies to the state of a liquid-liquid refrigerant in which a liquid refrigerant and a refrigerating machine oil that does not dissolve in a refrigerant flow, a gas-liquid-liquid refrigerant in which a refrigerating machine oil and a gas refrigerant that do not dissolve in a liquid refrigerant and a refrigerant flow, and the mixing section is a thin tube. In particular, if it is configured to satisfy Equations 1 and 2,
The refrigerant distributor has an effect of uniformly distributing the refrigerant. Further, if the branch space 5 is configured to satisfy Expressions 3 and 4, the refrigerant can be more uniformly distributed.

Embodiment 2 Hereinafter, a refrigerant distributor according to Embodiment 2 of the present invention will be described. FIG. 9 is a perspective view showing a refrigerant distributor according to the present embodiment. In the figure, reference numeral 6 denotes a stirring means for stirring the refrigerant in the mixing section 4 and the branch space 5, for example, a vibration element such as an ultrasonic self-exciting element or an electromagnetic vibration element which oscillates by supplying electricity from the outside, 1 and is attached to a portion corresponding to the branch space 5 outside.

In the present embodiment, the mixing section 4 and the branch space 5 are vibrated from outside the refrigerant distributor main body 1 by the vibrating element 6 to stir and mix the internal refrigerant. For this reason, the effect of stirring and mixing the gas-liquid two-phase refrigerant in the mixing section 4 and the branch space 5 is further ensured, and the refrigerant is more uniformly distributed. The same effect can be obtained by providing a stirring device such as a stirring impeller rotated by using a motor or a stirring impeller rotated by a refrigerant flow in the branch space 5 in the refrigerant distributor main body 1 as the stirring means. Play.

Embodiment 3 Hereinafter, a refrigerant distributor according to Embodiment 3 of the present invention will be described. FIG. 10 is a refrigerant circuit diagram showing a refrigeration cycle device such as an air conditioner or a refrigeration device using the refrigerant distributor according to the present embodiment. In the figure, 1 is a refrigerant distributor, 7 is a compressor, 8 is a condenser, 9
Is an expansion valve and 10 is an evaporator.

In the refrigeration cycle apparatus having such a configuration, the circulating refrigerant is divided into a plurality of, in this case, three paths in the refrigerant flow path between the expansion valve 9 and the evaporator 10.
Therefore, the refrigerant distributor 1 described in the first or second embodiment is disposed at this branch. Here, the mass flow rate W
In order to change [kg / s], for example, the rotation speed of the compressor 7 may be changed or the opening of the expansion valve 9 may be changed. By using this refrigerant distributor, the refrigerant can be evenly distributed to the three paths to the evaporator 10, and the performance and efficiency of the refrigeration cycle device can be improved.

In general, refrigerant noise is likely to be generated in a gas-liquid two-phase flow. It is considered that the cause of the generation of the refrigerant noise is that a non-uniform droplet flow collides with the tube wall and is generated. For example, in a refrigeration cycle device incorporating a refrigerant distributor in which the refrigerant circulates in a heterogeneous flow, the noise of the refrigerant may be annoying and may be one of the causes of the defect. Therefore, in the present embodiment, when configuring the refrigeration cycle apparatus, as shown in FIG. 10, the mixing section and the branch space configured by the thin tubes are optimally configured using the mass flow rate of the refrigerant, and the gas-liquid two-phase refrigerant Since a refrigerant distributor capable of achieving homogenization of the refrigerant is used, generation of refrigerant noise in the refrigeration cycle device can be prevented. As described above, in this embodiment, the performance and efficiency of the refrigeration cycle device are improved by uniformly distributing the refrigerant, and reliability problems caused by the non-uniform distribution of the refrigerant, for example, generation and evaporation of refrigerant noise It also has the effect of preventing dew dropping in containers.

FIG. 11 shows a plurality of indoor units 1.
1 and 2 show a multi-type air conditioner in which the outdoor unit 12 is connected in parallel, in which the refrigerant distributor according to the first or second embodiment is used for distributing the refrigerant from the main refrigerant flow path to each unit. It is a refrigerant circuit diagram. In the figure, 11a is a heat exchanger of the indoor unit 11, and 12a is a heat exchanger of the outdoor unit 12. In the present embodiment,
The refrigerant distributors 1 are disposed at two locations: a location branched to a plurality of indoor units 11 and a coolant flow path branched to a plurality of outdoor units 12. The refrigerant distributor according to the first or second embodiment exerts an effect of uniformly distributing the refrigerant to each of the indoor unit 11 and the outdoor unit 12, thereby improving the performance and efficiency of the air conditioner and generating refrigerant noise. It also has the effect of preventing dew dropping in the evaporator. In the above multi-type air conditioner, two refrigerant distributors 1 are provided at the branch portion.
Since the refrigerant flowing into the indoor unit 11 is not in a gas-liquid two-phase state, the state of the circulating refrigerant does not change so much even if the refrigerant distributor at the branch is omitted.

Embodiment 4 FIG. Hereinafter, a refrigerant distributor according to Embodiment 4 of the present invention will be described. FIG.
FIG. 9 is a characteristic diagram showing test results for examining the flow state of the refrigerant flowing into the mixing unit 4 in the gas-liquid two-phase state by changing the dimensions of each part, the gas-liquid flow ratio, and the like in the refrigerant distributor having the same structure as that of FIG. . The vertical and horizontal axes in FIG. 12 are values representing the flow state of the refrigerant, respectively, and the vertical axis is Gg / λ, which indicates the magnitude of the mass flow rate of the refrigerant, and the larger the value, the higher the value. Also,
The horizontal axis is λ × ψ × Gl / Gg, which indicates the ratio between the gas mass flow rate and the liquid mass flow rate of the refrigerant, that is, the degree of dryness. The degree of dryness decreases toward the right and the liquid becomes rich. However, each parameter in the above equation represents the following. λ = [(ρg / ρa) × (ρl / ρw)] ^1/2 ψ = (σw / σ) × [(μl / μw) × (ρw / ρl)
² ] ^1/3 Gg [kg / m ² · h]: Mass flow rate of gas refrigerant Gl [kg / m ² · h]: Mass flow rate of liquid refrigerant ρ: Density σ: Surface tension μ: Viscosity coefficient Subscript g, l , A, and w represent gas, liquid, air, and water, respectively.

The flow state of the refrigerant shown in FIG. 12 will be described below with reference to FIG. In FIG. 13, (a) a stratified flow,
The flow state called (b) wavy flow and (c) slug flow are as follows:
This is an example in which the drift of the gas-liquid two-phase refrigerant is large.
The flow state called (e) bubble flow and (f) annular spray flow is a state in which the gas-liquid two-phase refrigerant is mixed and stirred. FIG.
In the graph shown in FIG. 2, regions indicating the flow state of the refrigerant are divided according to the values on the vertical and horizontal axes. Here, FIG. 14 shows test results obtained by examining the refrigerant distribution ratio in the outlet pipe under the conditions indicated by the black circles and the white circles in FIG. FIG.
Reference numeral 4 denotes a refrigerant distributor having the configuration shown in FIG. 4, in which the vertical axis represents the refrigerant distribution ratio of the lower outlet pipe 3a, and the horizontal axis represents λ × ψ × Gl.
4 is a graph showing / Gg. In FIG. 14, the practical allowable range where the performance is not reduced by the distribution ratio of the two outflow pipes is set to 48% to 52%, and is shown within the range of the oblique line.
As is clear from the figure, all are included in the allowable range under the condition of the black circle, and all are out of the allowable range under the condition of the white circle. 12 and 13, it can be seen that a good refrigerant distribution result can be obtained if the mixing section is in the state of the annular spray flow and the bubble flow.

Therefore, as is clear from FIG. 12, if the gas-liquid two-phase refrigerant at the inlet of the mixing section 4 is within the range satisfying the equations (5) and (6), the state of the annular spray flow from the bubble flow in the mixing section is changed. can get. Gg / λ> 5 × 10 ⁴ (5) λ × ψ × Gl / Gg> 20 (6) By configuring the mass flow rate of the refrigerant so as to satisfy Equations 5 and 6, The flow state of the refrigerant in the mixing section 4 is a state of mixing and stirring, and is homogenized without drift.
Therefore, the refrigerant in a homogeneous state is discharged from the outlet pipe, and the performance as the refrigerant distributor can be maintained.

Further, the refrigerant distributor according to the present embodiment is
The flow state of the gas-liquid two-phase refrigerant at the inlet of the mixing section 4 is represented by Gg / λ.
> 5 × 10 ⁴ and λ × ψ × Gl / Gg> 20, since the gas-liquid two-phase refrigerant can be homogenized, the generation of refrigerant noise caused by the circulation of the refrigerant as an inhomogeneous flow also occurs. It can also be prevented.

Although the refrigerant distributor having two outflow pipes 3a and 3b has been described here, even when there are three or more outflow pipes, the gas-liquid two-phase refrigerant at the inlet of the mixing section 4 is expressed by Formula 5 ,
If it is limited to the range that satisfies Equation 6, the refrigerant distributor exerts an effect of uniformly distributing the refrigerant.

The refrigerant distributor according to the present embodiment is
As described in the second embodiment, by providing stirring means by a vibrating element outside the refrigerant distributor main body 1, or by providing stirring means in the branch space 5 in the refrigerant distributor main body 1,
The effect of stirring and mixing the gas-liquid two-phase refrigerant in the mixing section 4 and the branch space 5 is further ensured, and the refrigerant is uniformly distributed.

The refrigerant distributor according to the present embodiment is
As described in the third embodiment, in a refrigeration cycle device such as an air conditioner or a refrigeration device, when the internal refrigerant flow path is divided into a plurality of paths by a heat exchanger acting as a condenser or an evaporator, heat exchange is prevented. It may be used in a branch portion for distributing the refrigerant to each path at the inlet of the vessel. Further, in a multi-type air conditioner in which a plurality of outdoor units or indoor units are connected in parallel, the multi-type air conditioner may be used as a branch portion for distributing a refrigerant from a main refrigerant flow path to each unit. By using such a refrigeration cycle device, the effect of uniformly distributing the refrigerant is exhibited, and the performance and efficiency of the refrigeration cycle device are improved, and reliability problems due to the non-uniform refrigerant distribution, for example, It also exerts the effect of preventing generation of refrigerant noise and dew dropping in the evaporator.

In the refrigerant distributor described in the first to fourth embodiments, when the type of refrigerant changes, for example, H
CFC-based refrigerant (including single refrigerant and mixed refrigerant such as R22)
And HFC-based refrigerants (R134a, R407C, R410
A, R404A, etc., including single refrigerant and mixed refrigerant), HC
System refrigerant (including single refrigerant and mixed refrigerant such as methane, ethane, propane, butane and isobutane) and other natural refrigerants (including single refrigerant and mixed refrigerant such as air, water and carbon dioxide)
The same applies to the mixed refrigerant of the refrigerants described above, and the effect of uniformly distributing the refrigerant is exhibited.

Further, the refrigerant distributor according to Embodiments 1 to 4 can be installed in a unit of an air conditioner or a refrigeration system, or installed outside the unit, regardless of the installation location. Has the same effect. Further, for example, in the first to fourth embodiments, the case where the refrigerant distributor is arranged horizontally is described. However, the refrigerant distributor is arranged vertically, or when the refrigerant distributor is slightly inclined from the vertical. Regardless of the arrangement state, the effect of uniformly distributing the refrigerant is exhibited.

Further, in the refrigerant distributor described in the first to fourth embodiments, if the inside diameter of the inflow pipe 2 is formed of a narrow tube similar to the inside diameter of the mixing section 4, the mixing section is connected to the inflow pipe 2. The function of No. 4 can be substituted, and the effect of uniformly distributing the refrigerant is exhibited.

Further, assuming that the refrigerant distributor according to the first embodiment and the refrigerant distributor according to the fourth embodiment are combined, the values of the respective parts shown in FIG. 1 are represented by L / D> 5, W / (π ×
^{D 2/4)> 500 (} π: circular constant), W / H> 2, and W / V> limited to the range indicated in 10, and the flow state of the gas-liquid two-phase refrigerant at the inlet of the mixing section 4 To Gg / λ> 5 × 10 ⁴
By limiting the range to λ × ψ × Gl / Gg> 20, the effect of more uniformly distributing the refrigerant is exhibited. In addition, by using this refrigerant distributor in a refrigeration cycle device, performance and efficiency are improved, and reliability problems due to non-uniform refrigerant distribution, such as generation of refrigerant noise and splashing in the evaporator, are achieved. It also has the effect of preventing such problems.

[0046]

As described above, according to the first aspect of the present invention, the refrigerant flowing from the inflow pipe is connected to the mixing section and the plurality of outflow pipes, and the refrigerant flowing from the mixing section is transmitted to the outflow pipe. The branching space is distributed to each of the two, and the mixing section is reduced to an inner diameter smaller than the pipe diameter of the inflow pipe, and is longer than the length in the flow direction such that the flow state of the refrigerant is reduced or accelerated and the flow state becomes a bubble flow or an annular spray flow. By using a small tube with an inner diameter of a significantly smaller length, the refrigerant is stirred and mixed without being affected by drift and without gas-liquid separation, regardless of the installation condition of the refrigerant distributor. There is an effect that a refrigerant distributor capable of distributing the refrigerant can be obtained.

According to the second aspect of the present invention, the refrigerant flowing from the mixing section is connected to the mixing section through which the refrigerant flowing from the inflow pipe passes and the plurality of outflow pipes, and the refrigerant flowing from the mixing section is distributed to each of the outflow pipes. With a branch space, the flow state of the refrigerant in the mixing section is configured to satisfy the following equation, regardless of the installation state of the refrigerant distributor, without gas-liquid separation without being affected by drift There is an effect that a refrigerant distributor that can stir and mix the refrigerant and uniformly distribute the refrigerant can be obtained. Gg / λ> 5 × 10 ⁴ and λ × ψ × Gl / Gg> 20 where λ = [(ρg / ρa) × (ρl / ρw)] ^1/2 ψ = (σw / σ) × [(μl / μw) × (ρw / ρl)
² ] ^1/3 Gg [kg / m ² · h]: Mass flow rate of gas refrigerant Gl [kg / m ² · h]: Mass flow rate of liquid refrigerant ρ: Density σ: Surface tension μ: Viscosity coefficient Subscript g, l , A, and w represent gas, liquid, air, and water, respectively.

According to a third aspect of the present invention, in the refrigerant distributor according to the first aspect, the inner diameter of the mixing section is set to D.
[M], and the length in the flow direction of the refrigerant is L [m],
Since the mixing unit is configured so that D and L satisfy L / D> 5, the refrigerant is stirred without being affected by the drift and without gas-liquid separation regardless of the installation state of the refrigerant distributor. ,
There is an effect that a refrigerant distributor that can mix and uniformly distribute the refrigerant is obtained.

The refrigerant distributor according to claim 4 of the present invention is the refrigerant distributor according to claim 3, wherein the inner diameter of the mixing section is D [m], and the mass flow rate of the refrigerant flowing through the mixing section is W [kg].
When / s] to, D, W ^{is, W / (π × D 2} /4)> 5
Since the mixing section is configured to satisfy 00 (π: pi), the refrigerant is stirred and mixed without being affected by the drift and without separating gas-liquid regardless of the installation state of the refrigerant distributor. In addition, there is an effect that a refrigerant distributor that can uniformly distribute the refrigerant can be obtained.

According to a fifth aspect of the present invention, in the refrigerant distributor according to any one of the first to fourth aspects, the height of the branch space in the flow direction of the refrigerant is H [m]. ,
Assuming that the mass flow rate of the refrigerant flowing through the mixing section is W [kg / s], the branch space is configured to satisfy W / H> 2. Thus, there is an effect that a refrigerant distributor that can stir and mix the refrigerant without causing gas-liquid separation and uniformly distribute the refrigerant can be obtained.

According to a sixth aspect of the present invention, in the refrigerant distributor according to any one of the first to fifth aspects, the volume of the branch space is V [m ³ ], and the refrigerant flows through the mixing section. Assuming that the mass flow rate of the refrigerant is W [kg / s], W / V> 1
By configuring the branch space to satisfy 0,
Irrespective of the installation state of the refrigerant distributor, there is an effect that a refrigerant distributor that can stir and mix the refrigerant without being affected by the drift and without gas-liquid separation and uniformly distribute the refrigerant can be obtained.

According to a seventh aspect of the present invention, in the refrigerant distributor according to any one of the first to sixth aspects, the refrigerant flowing through at least one of the mixing section and the branch space is mixed. A refrigerant that can stir and mix the refrigerant reliably without gas flow separation without being affected by the drift, regardless of the installation state of the refrigerant distributor, and can uniformly distribute the refrigerant regardless of the installation state of the refrigerant distributor. There is an effect that a distributor can be obtained.

According to an eighth aspect of the present invention, the refrigerant distributor according to any one of the first to seventh aspects is provided at a refrigerant branch portion of a refrigerant flow path for circulating a refrigerant. As a result, a refrigeration cycle device that can improve the performance and efficiency of the refrigeration cycle device and prevent reliability problems due to non-uniform refrigerant distribution, such as generation of refrigerant noise and dew dropping in the evaporator, is obtained. Has the effect.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a refrigerant distributor according to Embodiment 1 of the present invention.

FIG. 2 is an explanatory diagram showing a state of a refrigerant in a refrigerant distributor main body according to the first embodiment.

FIG. 3 is a perspective view showing the refrigerant distributor when two outflow pipes are installed in a horizontal direction according to the first embodiment.

FIG. 4 is a perspective view showing the refrigerant distributor when two outflow pipes are installed in the vertical direction according to the first embodiment.

FIG. 5 relates to the first embodiment, and the inside diameter of the mixing section is D.
6 is a graph showing the relationship between L / D and distribution ratio when [m] and length are L [m].

FIG. 6 is a graph showing a relationship between a mass flow rate W [kg / s] of a refrigerant flowing through a mixing section and a distribution ratio according to the first embodiment.

FIG. 7 relates to the first embodiment, and the height of the branch space is H.
4 is a graph showing the relationship between W / H and distribution ratio when [m], the inner diameter of the mixing section is D [m], and the mass flow rate of the refrigerant flowing through the mixing section is W [kg / s].

FIG. 8 relates to the first embodiment, and the height of the branch space is H
[M], the volume is V [m ³ ], the inner diameter of the mixing section is D [m],
It is a graph which shows the relationship of W / V and distribution ratio when the mass flow rate of the refrigerant | coolant which flows through a mixing part is set to W [kg / s].

FIG. 9 is a perspective view showing a refrigerant distributor according to Embodiment 2 of the present invention.

FIG. 10 is a refrigerant circuit diagram of a refrigeration cycle apparatus using a refrigerant distributor according to Embodiment 3 of the present invention.

FIG. 11 is a refrigerant circuit diagram of a multi-type air conditioner using a refrigerant distributor according to Embodiment 3.

FIG. 12 is a characteristic diagram illustrating a flow state of a gas-liquid two-phase refrigerant at an inlet of a mixing unit in a refrigerant distributor according to Embodiment 4 of the present invention.

FIG. 13 shows a refrigerant distributor according to a fourth embodiment.
It is explanatory drawing showing the flow mode of the gas-liquid two-phase refrigerant.

FIG. 14 relates to the fourth embodiment, and shows the flow state λ × ψ × G
4 is a graph showing a relationship between l / Gg and a distribution ratio.

FIG. 15 is a sectional view showing a conventional refrigerant distributor.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Refrigerant distributor main body, 2 Inflow pipe, 3a, 3b outflow pipe, 4 mixing part, 5 branch space, 6 stirring means, 7 compressor, 8 condenser, 9 expansion valve, 10 evaporator, 11
Outdoor unit, 12 indoor units.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tomohiko Kasai 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Isao Funayama 2-3-2 Marunouchi 3-chome, Chiyoda-ku, Tokyo (72) Inventor Kunihiro Morishita 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsubishi Electric Corporation

Claims (8)

[Claims] 1. A cooling device, comprising: a mixing section that allows a refrigerant flowing from an inflow pipe to pass therethrough; and a branch space connected to a plurality of outflow pipes and distributing the refrigerant flowing from the mixing section to each of the outflow pipes. The mixing section has an inner diameter less than or equal to the pipe diameter of the inflow pipe and has an inner diameter much smaller than the length in the flow direction so that the flow state becomes a bubble flow or an annular spray flow by accelerating the flow. A refrigerant distributor comprising a thin tube. 2. A mixing section through which a refrigerant flowing from an inflow pipe passes, and a branch space connected to a plurality of outflow pipes for distributing the refrigerant flowing from the mixing section to each of the outflow pipes, A refrigerant distributor characterized in that the flow state of the refrigerant in the section satisfies the following expression. Gg / λ> 5 × 10 ⁴ and λ × ψ × Gl / Gg> 20 where λ = [(ρg / ρa) × (ρl / ρw)] ^1/2 ψ = (σw / σ) × [(μl / μw) × (ρw / ρl)
² ] ^1/3 Gg [kg / m ² · h]: Mass flow rate of gas refrigerant Gl [kg / m ² · h]: Mass flow rate of liquid refrigerant ρ: Density σ: Surface tension μ: Viscosity coefficient Subscript g, l , A, and w represent gas, liquid, air, and water, respectively. 3. The mixing unit is configured so that D and L satisfy L / D> 5, where D [m] is the inner diameter of the mixing unit and L [m] is the length in the flow direction of the refrigerant. The refrigerant distributor according to claim 1, wherein: 4. When the inner diameter of the mixing section is D [m] and the mass flow rate of the refrigerant flowing through the mixing section is W [kg / s],
W ^{is, W / (π × D 2} /4)> 500: refrigerant distributor according to claim 2, characterized in that constitute the mixing section so as to satisfy the ([pi pi). 5. The height of the branch space in the flow direction of the refrigerant is H
[M], the mass flow rate of the refrigerant flowing through the mixing section is W [kg /
5. The refrigerant distributor according to claim 1, wherein the branch space is configured to satisfy W / H> 2. 6. Assuming that the volume of the branch space is V [m ³ ] and the mass flow rate of the refrigerant flowing through the mixing section is W [kg / s], W /
The refrigerant distributor according to any one of claims 1 to 5, wherein the branch space is configured to satisfy V> 10. 7. The refrigerant distributor according to claim 1, further comprising stirring means for mixing the refrigerant flowing in at least one of the mixing section and the branch space. 8. A refrigeration cycle apparatus, wherein the refrigerant distributor according to claim 1 is provided at a refrigerant branch of a refrigerant flow path for circulating a refrigerant.