JPH09280670A - Heat exchanger - Google Patents

Abstract

PROBLEM TO BE SOLVED: To uniformly distribute a refrigerant over a plurality of heat transfer pipes with the uniform degree of drying, and demonstrate heat exchange efficiency to the utmost even when a flow rate of air heat exchanging with the refrigerant is changed by setting the degree of drying of the refrigerant to be a set value or more upon the refrigerant being distributed and hence making a flow of the refrigerant in a refrigerant piping axially symmetrically. SOLUTION: Distributers 3 for distributing a refrigerant are disposed at inlets of three systems of heat transfer pipes 2a to 2c passing through fins 1a to 1c in a heat exchanger, and means 5a to 5c constructed with capillary tubes for controlling a distribution flow rate of the refrigerant are interposed between the distributors 3 and outlets of the heat transfer pipes 2a to 2c. There are connected with the upstream side of the distributors 3 a drawing apparatus 7 and a subheat exchanger 6 for ther dergree of drying. The high temperature high pressure refrigerant is drawn with the drawing apparatus 7 up to low pressure, and the degree of drying of the refrigerant is set to be within a range of from 0.05 to 0.25. The refrigerant is heated through heat exchanges with air in the successive subheat exchanger 6 to set the degree of drying to 0.25 or more whereby distribution of the refrigerant in each heat transfer pipe 2a to 2c is made uniform.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger having a function of adjusting the degree of dryness of a refrigerant before the refrigerant is distributed to a plurality of refrigerant passages in a heat exchange section.

[0002]

2. Description of the Related Art FIG. 11 shows, for example, JP-A-7-3182.
This is a conventional heat exchanger shown in Japanese Patent Publication No. 76-76. In FIG. 11, 1a and 1b are fins, 2a and 2b are heat transfer tubes, and 4 and 4a and 4b are refrigerant flow paths. Where a, b
Indicates that there are two systems of the refrigerant circuit system in the heat exchanger and the fins attached to the refrigerant circuit.

Reference numeral 3 denotes a distributor for distributing the refrigerant into a plurality of refrigerant passages, which is located at the inlets of the refrigerant passages 4a and 4b formed by connecting the heat transfer tubes 2a and 2b, such as a packed tower. It has a function of separating the non-azeotropic mixed refrigerant into a plurality of non-azeotropic mixed refrigerants having different composition ratios.

Further, the pitch of the fins 1b through which the refrigerant flow path 4b in which the low boiling point refrigerant flows is larger than the pitch of the fins 1a in which the refrigerant flow path 4a through which the high boiling point refrigerant flows passes. It is arranged.

[0005]

In the conventional exchanger as described above, the ratio of the gas and the liquid of the refrigerant distributed in the respective refrigerant flow paths in the distributor varies irregularly, and the latent heat of vaporization on the refrigerant side and the air side There is a problem that the heat load is not properly balanced in each refrigerant flow path, and the heat exchanger cannot be effectively used.

The present invention has been made to solve the above problems, and in a heat exchanger having a plurality of refrigerant flow paths, the efficiency of the heat exchanger can be improved even if the flow rate of air for heat exchange with the refrigerant changes. The purpose is to obtain a heat exchanger that can maximize its performance.

[0007]

In order to achieve the above object, a heat exchanger according to the present invention has fins arranged at regular intervals and heat transfer tubes penetrating the fins. Refrigerant in the heat pipe, in the heat exchanger that flows air outside the heat transfer pipe, a refrigerant circuit that forms a plurality of refrigerant flow paths communicating the heat transfer pipe, is provided on the inlet side of the refrigerant circuit, in the refrigerant circuit A throttle means for controlling the flow rate of the refrigerant and a first means for detecting the temperature at the inlet side and the outlet side of the refrigerant circuit.
And a second temperature detection means, a throttle control means for controlling the opening degree of the throttle means based on the values detected by the first and second temperature detection means, and air for exchanging heat with the refrigerant in the refrigerant circuit. Blower means for blowing air, blower control means for controlling the number of revolutions of the blower means, timing means for measuring the control timing of the throttle control means and the blower control means, and a refrigerant provided on the inlet side of the refrigerant circuit. Dryness control means for controlling the degree of dryness, distribution means for distributing the refrigerant to a plurality of refrigerant flow paths, and a refrigerant pipe that connects the distribution means and the plurality of refrigerant flow paths, and each refrigerant flow And a refrigerant flow rate control means for controlling the distribution flow rate to the passage.

In this invention, when distributing the refrigerant,
By setting the dryness of the refrigerant to a predetermined value or more, the flow in the refrigerant pipe becomes an axially symmetrical flow, and the refrigerant can be distributed to the plurality of heat transfer tubes with an even dryness. Therefore, the refrigerant flow rate distributed to the plurality of heat transfer tubes depends on the refrigerant flow rate control means arranged on the heat transfer tube inlet side, whereby
The flow rate of the refrigerant flowing through each refrigerant channel can be controlled.

A heat exchanger according to the next invention has fins arranged at regular intervals and a heat transfer tube penetrating the fins, and a heat exchange in which a refrigerant flows in the heat transfer tube and air flows outside the heat transfer tube. In a container, a refrigerant circuit in which a plurality of refrigerant channels are formed by communicating the heat transfer tubes, and is provided on the inlet side of the refrigerant circuit,
Throttle means for controlling the flow rate of the refrigerant in the refrigerant circuit,
First and second temperature detecting means for detecting the temperatures at the inlet side and the outlet side of the refrigerant circuit, and the opening degree of the throttle means is controlled based on the values detected by the first and second temperature detecting means. Throttle control means, air blowing means for blowing air that exchanges heat with the refrigerant in the refrigerant circuit, air blowing control means for controlling the number of revolutions of the air blowing means, and timings for controlling the throttle control means and the air blowing control means A timer and a dryness control means for controlling the dryness of the refrigerant, which is provided on the inlet side of the refrigerant circuit and has an outlet through which the refrigerant flows from above and below in a container having a constant volume, and a plurality of dryness control means. Distributing means for distributing the refrigerant to the refrigerant flow path, a refrigerant pipe connecting the distributing means and the refrigerant flow path, and a refrigerant pipe connecting the dryness control means and the refrigerant flow path, respectively Is one in which comprises a refrigerant flow control means for controlling the distribution rate for each of the refrigerant flow path, a.

In the present invention, the distribution container serving as the dryness control means is in a state in which the gas-liquid two-phase refrigerant is in the upper part gas and the lower part is liquid. At this time, by controlling the refrigerant flow rate of the liquid taken out from the lower portion by the refrigerant flow rate control means, the refrigerant in the gas-liquid two-phase state fixed to a certain dryness flows out from the refrigerant pipe. Therefore, the dryness of the refrigerant flowing out from the refrigerant pipe becomes larger than the dryness of the refrigerant flowing into the distribution container, and the magnitude of the change in the dryness is controlled by controlling the liquid refrigerant flow rate taken out from the refrigerant pipe. decide.

In the heat exchanger according to the next invention, the refrigerant pipe drawn out from the lower part of the dryness control means is connected to the refrigerant passage in which the speed of the air passing through the refrigerant circuit is high while exchanging heat with the refrigerant. It is a thing.

In the present invention, the latent heat of vaporization of the refrigerant increases as the dryness of the refrigerant decreases. Therefore, if the dryness of the refrigerant is the same, the heat exchange amount on the refrigerant side increases as the dryness decreases. Therefore, by connecting the heat transfer tube passing through a portion having a high wind speed and the refrigerant pipe connected below the distribution container, it is possible to balance the heat exchange capacities inside and outside the heat transfer tube.

A heat exchanger according to the next invention further comprises a refrigerant flow rate control means which is provided in a refrigerant flow path connected below the dryness control means and which controls a refrigerant flow rate of the refrigerant flow path, Third temperature detecting means for detecting the temperature at the outlet side of the heat transfer tube connected below the dryness control means,
The refrigerant flow rate control means controls the refrigerant flow rate based on the values detected by the first and third temperature detection means.

In the present invention, for example, when the rotation speed of the blower means is changed via the blower control means by the ambient temperature or an artificial operation, the air volume in the heat exchanger changes. When the air volume of the entire heat exchanger changes, the heat load of each heat transfer tube changes. On the other hand, by controlling the refrigerant flow rate by the refrigerant flow rate control means, even if the heat load changes, the refrigerant state at the outlet side of the refrigerant channel is always controlled to the saturated vapor state with a predetermined dryness. You can Therefore, the required amount of liquid refrigerant can be taken out from the distribution container, and
A refrigerant having a certain dryness can be discharged from the refrigerant pipe.

In the heat exchanger according to the next invention, the heat transfer efficiency of the heat transfer tube of the refrigerant passage drawn out from below the dryness control means is higher than the heat transfer efficiency of the heat transfer tubes of the other refrigerant passages. In addition, the shape of the fins attached to each is different.

In the present invention, the latent heat of vaporization of the refrigerant increases as the dryness of the refrigerant decreases. Therefore, if the dryness is the same, the heat exchange amount on the refrigerant side increases as the dryness decreases. Therefore, by connecting the heat transfer tube having the fins with high heat transfer efficiency and the refrigerant pipe connected below the distribution container, it is possible to balance the heat exchange capacities inside and outside the heat transfer tube.

In the heat exchanger according to the next invention, the heat transfer efficiency of the heat transfer tubes of the refrigerant passage drawn out from the lower part of the dryness control means is higher than the heat transfer efficiency of the heat transfer tubes of the other refrigerant passages. In addition, the inner surface shape of each heat transfer tube is different.

In the present invention, the latent heat of vaporization of the refrigerant increases as the dryness of the refrigerant decreases. Therefore, if the dryness is the same, the heat exchange amount on the refrigerant side increases as the dryness decreases. Therefore, by connecting the heat transfer tube and the refrigerant pipe connected to the lower side of the distribution container, and adopting a shape for promoting heat transfer such as an inner grooved tube to the heat transfer tube, The heat exchange capacity outside can be balanced.

A heat exchanger according to the next invention uses a non-azeotropic mixed refrigerant as the refrigerant.

In the present invention, a non-azeotropic mixed refrigerant is used as the refrigerant. Thus, when a non-azeotropic mixed refrigerant is used as the refrigerant, the composition of the liquid refrigerant flowing from below in the distribution container is different from that of the refrigerant flowing from above in the distribution container. Therefore, the average evaporation temperature of the refrigerant that flows into the heat transfer tube with a certain composition is higher than the average evaporation temperature of the refrigerant that flows into the heat transfer tube with another composition.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a heat exchanger according to the present invention will be described below in detail with reference to the drawings.

(Embodiment 1) First, Embodiment 1 will be described. 1 is an explanatory view showing the configuration of a heat exchanger according to a first embodiment of the present invention. In FIG. 1, 1
a, 1b, 1c are fins arranged in parallel.
The symbols a, b, and c indicate that there are three refrigerant circuit systems. Heat transfer tubes 2a, 2b, 2c are arranged so as to penetrate the fins 1a, 1b, 1c. A distributor 3 for distributing the refrigerant is installed at the inlets of the heat transfer tubes 2a to 2c of these three systems.

Further, 5a, 5b, 5c are means for controlling the distribution flow rate of the refrigerant, and are constituted by, for example, capillaries. The distributor 3 and the heat transfer tubes 2a, 2b and 2c are capillary tubes 5.
a, 5b, and 5c are connected to each other to connect the refrigerant flow paths 4a, 4b,
4c. A throttle device 7 is provided upstream of the distributor 3.
And the sub heat exchanger 6 for dryness control is connected and connected. At the outlets of the heat transfer tubes 2a, 2b, 2c,
Plural refrigerant pipes are merged and connected to a single refrigerant pipe 4.

Reference numeral 10 denotes an aperture controller for controlling the opening of the aperture device 7. Reference numeral 12 is a timer, and the aperture controller 1
The control timing of 0 is measured. 8 is a fan that blows air to the heat exchanger, and is controlled by the fan control device 9.
The number of rotations is controlled. Reference numeral 21 is a first temperature detector that detects the temperature between the sub heat exchanger 6 and the distributor 3, and reference numeral 22 is a second temperature detector that detects the temperature in the refrigerant pipe 4. The capillaries 5a, 5b, 5c are an example of means for controlling the flow rate of the refrigerant, and for example, a flow rate control valve or the like may be used.

Next, the operation of the first embodiment will be described. The high temperature / high pressure refrigerant is throttled to a low pressure by the expansion device 7. The dryness of the refrigerant at this time is usually in the range of 0.05 to 0.25. Therefore, in the sub heat exchanger 6, the refrigerant is heated by exchanging heat with the air to obtain a dryness of 0.25.
Set above.

The gas-liquid two-phase refrigerant is distributed by the distributor 3 to the heat transfer tubes 2a, 2b, 2c. Heat transfer tubes 2a-2c
The refrigerant is slightly throttled by the capillaries 5a, 5b, 5c before flowing into the. At this time, by changing the size of the capillaries 5a to 5c of each pass, it becomes possible to change (control) the refrigerant distribution amount of each pass.

When distributing the refrigerant, the dryness of the refrigerant is set to 0.2.
By setting it to 5 or more, the flow in the refrigerant pipe becomes an axially symmetrical flow, and the refrigerant can be distributed to the plurality of heat transfer tubes 2a to 2c with an even dryness. Therefore, the flow rate of the refrigerant distributed to the plurality of heat transfer tubes 2a to 2c depends on the way of narrowing the capillaries 5a, 5b, 5c at the heat transfer tube inlet, and thereby the flow rate of the refrigerant flowing through each refrigerant flow path can be controlled. .

FIG. 2 is a flow chart showing the control of the diaphragm device 7. When the apparatus is started, the timer 12 is reset in step S1 and the integrated time t = 0. In step S2, a certain time interval Δt is added to the integrated time t. In step S3, the integrated time t is compared with the preset control interval t ₀ . As a result, t
If> t ₀ , the process proceeds to step S4. If t <t ₀ , the process returns to step S2 and the time is further integrated.

Next, in step S4, the temperatures t ₁ and t ₂ are detected from the first temperature detector 21 and the second temperature detector 22. In step S5, SH = t ₂ −t ₁ is defined and SH is calculated. In step S6, the above step S
The SH obtained in 5 is compared with the SHm set in advance. As a result, when SH <SHm, step S
7, the opening degree of the expansion device 7 is reduced. Conversely, S
When H> SHm, the opening degree of the expansion device 7 is increased in step S8. When step S7 or step S8 ends, the process returns to step S1 again.

In the heat exchanger having a plurality of heat transfer tubes configured as described above, the amount of refrigerant required to evaporate in each heat transfer tube can be supplied without excess or deficiency.
The efficiency of the heat exchanger can be improved.

(Second Embodiment) Next, a second embodiment will be described. FIG. 3 shows a second embodiment according to the present invention.
It is explanatory drawing which shows the heat exchanger. The same parts as those of the first embodiment are designated by the same reference numerals and the description thereof will be omitted. In the second embodiment, the sub heat exchanger 6 shown in FIG. 1 is eliminated, and a distribution container 13 for distributing the refrigerant is provided instead of the sub heat exchanger 6, and the refrigerant pipe 10 is provided from the upper and lower parts of the distribution container 13.
0a and 100b are pulled out, and the heat transfer tube 2 is connected through the distributor 3.
a, 2b, 2c.

An electromagnetic valve 11 is installed in the middle of the refrigerant pipe 100b connected to the lower portion of the distribution container 13. Although the second embodiment shows an example in which only the refrigerant pipe 100a drawn from the upper portion of the distribution container 13 is branched,
The refrigerant pipe 100b may be branched, or the refrigerant pipes 100a and 100b may be branched together.

Next, the operation of the second embodiment will be described. In the distribution container 13, the refrigerant in the gas-liquid two-phase state is in the state of gas in the upper part and liquid in the lower part. At this time, by controlling the refrigerant flow rate of the liquid taken out from the lower portion by the capillary tube 5c, the refrigerant in a gas-liquid two-phase state fixed to a certain degree of dryness flows out from the refrigerant pipe 100a.

At this time, the dryness of the refrigerant flowing out from the refrigerant pipe 100a becomes larger than the dryness of the refrigerant flowing into the distribution container 13, and the magnitude of the change in the dryness is the liquid taken out from the refrigerant pipe 100b. It can be determined by controlling the refrigerant flow rate. Further, the solenoid valve 11 is closed at the time of starting, and prevents liquid back at the time of starting in the refrigeration cycle.

With the above structure, the dryness immediately before the distributor can be easily changed, and the dryness can be adjusted so that the gas-liquid distribution can be appropriately performed.
The performance of the heat exchanger can be improved at low cost.

(Third Embodiment) Next, a third embodiment will be described. FIG. 4 shows a third embodiment according to the present invention.
It is explanatory drawing which shows the heat exchanger. The same parts as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.
FIG. 5 shows an example of air volume distribution in a direction perpendicular to the longitudinal direction of the heat transfer tube. Usually, the heat exchanger has a distribution of air volume as shown in Fig. 5. Therefore, the heat exchangeable heat quantity in the heat transfer tube changes depending on the refrigerant flow path of the heat exchanger, and the heat exchange is possible as the air volume increases. The amount of heat exchange increases.

On the other hand, the latent heat of vaporization of the refrigerant increases as the dryness of the refrigerant decreases. Therefore, if the dryness is the same, the heat exchange amount on the refrigerant side increases as the dryness decreases. Therefore, by connecting the heat transfer pipe 2c passing through a portion having a high wind speed and the refrigerant pipe 100b connected below the distribution container 13, the heat exchange capacities inside and outside the heat transfer pipe can be balanced.
On the other hand, the heat transfer tubes 2a and 2b passing through a portion having a small air volume and the refrigerant pipe 100a drawn from above the distribution container 13.
The heat exchange amount inside and outside the heat transfer tube can be balanced by connecting the heat transfer tubes. As a result, the heat exchanger can balance the distribution amount of the refrigerant and the heat exchange between the air passing outside the heat transfer tube.

With the above structure, the dryness of the refrigerant drawn from the upper portion of the distribution container 13 can be controlled to a dryness suitable for distribution, and the heat load of each refrigerant flow path due to the air flow distribution outside the pipes. Since a proper refrigerant distribution balanced with is achieved, the performance of the heat exchanger can be further improved.

(Fourth Embodiment) Next, a fourth embodiment will be described. FIG. 6 shows a fourth embodiment according to the present invention.
2 is an explanatory view showing the heat exchanger of FIG. 1, and the same parts as those in Embodiment 1 are designated by the same reference numerals and the description thereof will be omitted.
In FIG. 6, the capillary tube 5c shown in FIG. 1 is abolished to be a refrigerant flow rate control valve 15c, and the third temperature detector 23 and the opening degree of the refrigerant flow rate control valve 15c are controlled at the outlet of the heat transfer tube 2c. The control valve control device 14 is added.

Next, the operation of the fourth embodiment will be described. FIG. 7 is a flowchart showing the control operation of the refrigerant flow rate control valve 15c. When the device is started, step S1
At 1, the timer 12 is reset and the integrated time t = 0. Here, the integrated time t does not necessarily have to match the integrated time when the diaphragm device 7 is controlled. In step S12, the time interval Δt in the integrated time t is added.

In step S13, the accumulated time t and the preset time are set.
Predetermined control interval t₀Make a size comparison. as a result,
t> t₀If so, the process proceeds to step S14. On the contrary, t
<T ₀If so, go back to step S12 and spend more time.
Add up. In step S14, the first temperature detector 21
From the third temperature detector 23 and the temperature t₁, T_ThreeDetect
You.

In step S15, SH2 = t ₃ −t ₁
And SH2 is calculated. In step S16, SH2 obtained in step S15 is compared with SHm2 set in advance. As a result, when SH2 <SHm2, the opening degree of the expansion device 7 is reduced in step S17. On the contrary, when SH2> SHm2, the opening degree of the expansion device 7 is increased in step S18.
When step S17 or step S18 ends,
It returns to step S11 again.

Next, the operation when the rotation speed of the fan 8 changes will be described with reference to the graph of FIG. When the fan speed changes via the fan control device 9 due to the ambient temperature or an artificial operation, the air volume in the heat exchanger changes as shown in FIG. When the air volume of the entire heat exchanger changes, the heat load of each heat transfer tube changes.

On the other hand, by controlling the refrigerant flow rate control valve 15c, even if the heat load changes, the state of the refrigerant at the outlet of the refrigerant flow path 4c, for example, the state of saturated vapor having a dryness of 1.0, It is always possible to control. Therefore, the required amount of liquid refrigerant can be taken out from the distribution container 13, and the refrigerant having a certain dryness can be discharged from the refrigerant pipe 100a.

As a result, even if the total flow rate of the air passing through the heat exchanger changes, the state of the refrigerant at the outlet of the heat transfer tube 2c is always kept constant and the flow rate of the liquid flowing out from the distribution container 13 is kept at a proper level. In addition, since it is possible to let out a refrigerant having a certain dryness from the refrigerant pipe 100a above the distribution container 13, it is possible to improve the efficiency of the heat exchanger with respect to a wide change in the air flow rate. be able to.

(Fifth Embodiment) Next, a fifth embodiment will be described. FIG. 9 shows a fifth embodiment according to the present invention.
2 is an explanatory view showing the heat exchanger of FIG. 1, and the same parts as those in Embodiment 1 are designated by the same reference numerals and the description thereof will be omitted.
In the present embodiment, in FIG. 1, a fin having a high heat transfer performance, which is different from the fins 1a and 1b in the shape of the fin 1c, is used.

Since the latent heat of vaporization of the refrigerant increases as the dryness of the refrigerant decreases, the heat exchange amount on the refrigerant side increases as the dryness decreases for the same mass flow rate. Therefore, by connecting the heat transfer tube 2c having fins having good heat transfer performance and the refrigerant pipe 100b connected to the lower portion of the distribution container 13, the heat exchange capacity inside and outside the heat transfer tube can be balanced.

On the other hand, by connecting the heat transfer pipes 2a and 2b with fins having a small heat transfer performance to the refrigerant pipe 100a drawn from above the distribution container 13, the heat exchange amount inside and outside the heat transfer pipe can be balanced. As a result, as the heat exchanger, the distribution amount of the refrigerant and the heat exchange between the air passing outside the heat transfer tube are balanced, and the heat transfer area of the heat exchanger can be effectively utilized.

(Sixth Embodiment) Next, a sixth embodiment will be described. The schematic configuration of the heat exchanger according to the sixth embodiment is the same as that shown in FIG. 4, but in the present embodiment, the inner surfaces of the heat transfer tubes 2a and 2b shown in FIG. 4 are smooth tubes. The inner surface of the heat transfer tube 2c is a groove-shaped tube.

Since the latent heat of vaporization of the refrigerant increases as the dryness of the refrigerant decreases, the heat exchange amount on the refrigerant side increases as the dryness decreases for the same mass flow rate. Therefore, the heat transfer tube 2c
And the refrigerant pipe 100b connected to the lower part of the distribution container 13 are connected to each other, and the heat transfer pipe 2c uses a pipe having a shape for promoting heat transfer such as a grooved pipe on the inner surface. The exchange capacity can be balanced.

On the other hand, by connecting the heat transfer tubes 2a and 2b to the refrigerant pipe 100a drawn out from above the distribution container 13 and using heat transfer tubes having smooth inner surfaces for the heat transfer tubes 2a and 2b, heat exchange inside and outside the heat transfer tubes is also possible. The quantity can be balanced. As a result, as the heat exchanger, the distribution amount of the refrigerant and the heat exchange between the air passing outside the heat transfer tube are balanced, and the heat transfer area of the heat exchanger can be effectively utilized.

(Seventh Embodiment) Next, a seventh embodiment will be described. The schematic configuration of the heat exchanger of the seventh embodiment is the same as that shown in FIG. 4, but in the present embodiment, a non-azeotropic mixed refrigerant is used as the refrigerant.

When a non-azeotropic mixed refrigerant is used as the refrigerant, the composition of the liquid refrigerant flowing from below in the distribution container 13 and the composition of the refrigerant flowing from above in the distribution container 13 are different. This will be described with reference to the graph of FIG. FIG. 10 is a phase equilibrium diagram of a refrigerant in which the vertical axis represents the refrigerant temperature and the horizontal axis represents the refrigerant component ratio (hereinafter referred to as composition). In the figure, the composition A is the composition of the refrigerant before distribution. Further, the compositions B and C represent the compositions of the refrigerant that has become a two-phase state with the liquid.

It can be seen from FIG. 10 that the saturated gas temperature TC of the composition C is higher than the saturated gas temperature TB of the composition B. Therefore, the average evaporation temperature of the refrigerant flowing into the heat transfer tube with the composition C is higher than the average evaporation temperature of the refrigerant flowing into the heat transfer tube with the composition B. Further, since the refrigerant of the composition C is in a liquid state with a dryness of 0, the latent heat of the refrigerant is large. Therefore, when the inner surface of the heat transfer tube 2c has a groove, the high boiling point component can be efficiently evaporated.

Therefore, in the heat exchanger having the structure of the present embodiment (see FIG. 4), the performance of the heat exchanger can be further improved by using the non-azeotropic mixed refrigerant as the refrigerant.

In this embodiment, an example in which a non-azeotropic mixed refrigerant in which two kinds of refrigerants are mixed is used as the non-azeotropic mixed refrigerant is shown. However, a non-azeotropic mixed refrigerant in which three or more kinds of refrigerants are mixed is shown. The same effect is obtained even when a refrigerant is used.

[0057]

As described above, in the heat exchanger according to the present invention, the dryness control means for controlling the dryness of the refrigerant is provided on the inlet side of the heat exchanger, and the refrigerant is distributed to the plurality of refrigerant flow paths. For the purpose of proper distribution of the gas-liquid two-phase of the refrigerant, since the refrigerant flow rate control means is provided in the middle of the pipe that connects the distributor and the inlet side of the refrigerant circuit having a plurality of refrigerant flow paths to the distributor. In addition, the required amount of refrigerant can be supplied to each refrigerant circuit without excess or deficiency, and the heat exchange performance of the heat exchanger can be improved.

In the heat exchanger according to the next invention, the dryness immediately before the distributor can be easily controlled, and the dryness can be controlled so that gas-liquid distribution can be appropriately performed.
The heat exchange performance of the heat exchanger can be improved at low cost.

In the heat exchanger according to the next invention, a refrigerant flow rate control means is added between the refrigerant pipe drawn from the lower side of the distribution container and the heat transfer pipe, and the dryness of the refrigerant taken out from the upper part of the distribution container is increased. Can be controlled to a dryness suitable for distribution, and proper refrigerant distribution that balances the heat load of each refrigerant flow path due to the air flow distribution outside the pipe can be achieved, so the heat exchange of the heat exchanger can be achieved. The performance can be further improved.

In the heat exchanger according to the next invention, the flow rate of the liquid refrigerant drawn from the distribution container is properly controlled even when the air volume changes, and a constant degree of dryness is obtained from the pipe above the distribution container. Since the refrigerant can flow out, the heat exchange efficiency of the heat exchanger can be improved with respect to a wide change in the air flow rate.

In the heat exchanger according to the next invention, since the shape (pattern) of the fins is changed depending on the refrigerant flow path, the evaporation capacity of the refrigerant and the heat exchange capacity of the air can be made substantially equal to each other. The heat transfer area of the exchanger can be effectively utilized.

In the heat exchanger according to the next invention, since the shape of the inner surface of the heat transfer tube is changed depending on the refrigerant flow path, the evaporation capacity of the refrigerant and the heat exchange capacity of the air can be made substantially equal to each other. The heat transfer area of the exchanger can be effectively utilized.

In the heat exchanger according to the next invention, the high boiling point component in the non-azeotropic mixed refrigerant can be efficiently evaporated, and the heat exchange performance of the heat exchanger can be further improved.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of a heat exchanger according to a first embodiment of the present invention.

FIG. 2 is a flowchart showing a method of controlling the diaphragm device according to the first embodiment.

FIG. 3 is an explanatory diagram showing a configuration of a heat exchanger according to a second embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a configuration of a heat exchanger according to a third embodiment of the present invention.

FIG. 5 is an air volume distribution diagram showing the difference in air volume with respect to the refrigerant flow path of the heat exchanger.

FIG. 6 is an explanatory diagram showing a structure of a heat exchanger according to a fourth embodiment of the present invention.

FIG. 7 is a flowchart showing a method of controlling a refrigerant flow rate control valve according to the fourth embodiment.

FIG. 8 is a graph showing changes in the air flow distribution in the heat exchanger when the air flow changes.

FIG. 9 is an explanatory diagram showing a structure of a heat exchanger according to a fifth embodiment of the present invention.

FIG. 10 is a phase equilibrium diagram showing a composition in a gas-liquid two-phase state in a mixed refrigerant.

FIG. 11 is an explanatory diagram showing a configuration of a conventional heat exchanger.

[Explanation of symbols]

1a, 1b, 1c fins, 2a, 2b, 2c heat transfer tubes, 3 distributors, 4 refrigerant pipes, 4a, 4b, 4c refrigerant flow paths, 5a, 5b, 5c capillaries, 6 sub heat exchangers, 7 throttle devices, 8 Fan, 9 fan controller,
10 throttle controller, 11 solenoid valve, 12 timer, 13
Distribution container, 14 Control valve control device, 15c Refrigerant flow rate control valve, 21 First temperature detector, 22 Second temperature detector, 23 Third temperature detector, 100a, 100b Refrigerant piping

Claims (7)

[Claims] 1. A heat exchanger having fins arranged at regular intervals and a heat transfer tube penetrating the fins, wherein a refrigerant flows in the heat transfer tube and air flows outside the heat transfer tube. A refrigerant circuit having a plurality of refrigerant channels formed therein, a throttle means provided at the inlet side of the refrigerant circuit for controlling the refrigerant flow rate in the refrigerant circuit, and a temperature at the inlet side and the outlet side of the refrigerant circuit being detected. First and second temperature detecting means, throttle control means for controlling the opening degree of the throttle means based on the values detected by the first and second temperature detecting means, and heat exchange with the refrigerant in the refrigerant circuit. Blowing means for blowing the air to be blown, blowing control means for controlling the number of revolutions of the blowing means, time measuring means for measuring the control timing of the throttle control means and the blowing control means, and an inlet side of the refrigerant circuit. A dryness control means for controlling the dryness of the refrigerant, a distributing means for distributing the refrigerant to a plurality of refrigerant flow paths, and a refrigerant pipe connecting the distributing means with the plurality of refrigerant flow paths. A refrigerant flow rate control means for controlling a distribution flow rate for each refrigerant flow path, and a heat exchanger. 2. A heat exchanger having fins arranged at regular intervals and a heat transfer tube penetrating the fins, wherein a refrigerant flows in the heat transfer tube and air flows outside the heat transfer tube. A refrigerant circuit having a plurality of refrigerant channels formed therein, a throttle means provided at the inlet side of the refrigerant circuit for controlling the refrigerant flow rate in the refrigerant circuit, and a temperature at the inlet side and the outlet side of the refrigerant circuit being detected. First and second temperature detecting means, throttle control means for controlling the opening degree of the throttle means based on the values detected by the first and second temperature detecting means, and heat exchange with the refrigerant in the refrigerant circuit. Blowing means for blowing the air to be blown, blowing control means for controlling the number of revolutions of the blowing means, time measuring means for measuring the control timing of the throttle control means and the blowing control means, and an inlet side of the refrigerant circuit. Is at a container having a fixed volume, an outlet for the refrigerant flows out from the upper and lower,
Dryness control means for controlling the degree of dryness of the refrigerant, distribution means for distributing the refrigerant to a plurality of refrigerant flow paths, refrigerant piping connecting the distribution means and the refrigerant flow path, and the dryness control means and the refrigerant A heat exchanger comprising: a refrigerant flow rate control means, each of which is provided in the middle of a refrigerant pipe connecting the flow path, and controls a distribution flow rate to each refrigerant flow path. 3. The refrigerant pipe drawn out from below the dryness control means is connected to a refrigerant flow path in which the velocity of the air passing through the refrigerant circuit is high while exchanging heat with the refrigerant. The heat exchanger described in. 4. A refrigerant flow rate control means provided in a refrigerant flow path connected below the dryness control means for controlling a refrigerant flow rate of the refrigerant flow path, and below the dryness control means. Third temperature detecting means for detecting the temperature at the outlet side of the connected heat transfer tube, wherein the refrigerant flow rate control means is configured to detect the temperature of the refrigerant based on the values detected by the first and third temperature detecting means. The heat exchanger according to claim 2 or 3, which controls the heat exchanger. 5. The shape of the fins attached to each of the fins so that the heat transfer efficiency of the heat transfer tubes of the refrigerant flow path drawn out from the lower side of the dryness control means is higher than the heat transfer efficiency of the heat transfer tubes of the other refrigerant flow paths. The heat exchanger according to any one of claims 2 to 4, characterized in that 6. The inner surface shape of each heat transfer tube such that the heat transfer efficiency of the heat transfer tube of the refrigerant flow path drawn out from the lower side of the dryness control means is higher than the heat transfer efficiency of the heat transfer tubes of the other refrigerant flow paths. Are different from each other, The heat exchanger according to any one of claims 2 to 5. 7. The heat exchanger according to claim 1, wherein a non-azeotropic mixed refrigerant is used as the refrigerant.