JP3367467B2 - Finned heat exchanger - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a finned heat exchanger mainly used in an air conditioner or the like.

[0002]

2. Description of the Related Art A first conventional example of a recent finned heat exchanger will be described with reference to FIGS. Figure 8
Is a perspective view showing the basic configuration of a heat exchanger with fins, and FIG. 9 is a side view thereof. As shown in FIGS. 8 and 9, the heat exchanger with fins includes the auxiliary heat exchanger 101a and the main heat exchanger 101.
b. The auxiliary heat exchanger 101a is composed of a fin group 102a arranged in parallel at a predetermined interval and a heat transfer tube group 103a forming a row penetrating the fin group at a substantially right angle and arranged on the gas inflow side (a). There is. The main heat exchanger 101b includes a fin group 102b arranged in parallel at a predetermined interval,
A group of heat transfer tubes 10 forming a row penetrating the fin group at a substantially right angle.
3b and is arranged on the gas outflow side (b). 1
Reference numeral 04 denotes an air flow, which flows through the fin group 102a and the fin group 102b in the direction of the arrow, and the heat transfer tube group 103a and the heat transfer tube group 103.
Heat exchange with the fluid flowing in the tube of b. When this heat exchanger with fins is mounted on an indoor unit of a separate type air conditioner, it is common to provide cutting portions at several points of the fin group 102b and bend the several points for mounting. Is.

In the above structure, when used as a condenser of a refrigeration cycle of an air conditioner, the fluid flowing in the heat transfer tubes flows in the vapor phase state from the arrow A side, and the branch portion 105 moves the heat transfer tube group 103b up and down. To a liquid state through a gas-liquid two-phase state by heat exchange with the air flow 104, merges again at the branching portion 106, and flows out to the arrow B side through the heat transfer tube group 103a. As described above, in the finned heat exchanger, the fluid flowing in the heat transfer tube group 103a is almost in a liquid state and the fluid flowing in the heat transfer tube group 103b is in a gas phase state or a gas-liquid two-phase state. It is composed of a heat exchanger 101b.

Therefore, the heat transfer tube group 103 as the refrigerant piping
The number of flow paths of a becomes smaller as it approaches the refrigerant outlet,
Further, the auxiliary heat exchanger 101a, which is arranged on the gas inflow side (a) which is the windward side of the air flow 104 in the main flow direction and which is the low temperature part on the condenser outlet side, is separated from the main heat exchanger 101b, thereby leeward side. It is possible to block the heat conduction to the gas outflow side, and to improve the condensing performance by facilitating supercooling.

A second conventional example is Japanese Patent Laid-Open No. 57-12.
A representative drawing of Japanese Patent No. 7732 is shown in FIG. FIG. 10 is a perspective view of the heat exchanger. Finned heat exchanger 101c
Is composed of heat transfer tube groups 103c and 103d, and a large number of fins 102c mounted orthogonally thereto.

When used as a condenser of a refrigerating cycle of an air conditioner, in the finned heat exchanger 101c, the high-temperature and high-pressure gas refrigerant passes through the heat transfer tube group 103c, and the heat transfer tube group 1
It flows to the 03d side. Meanwhile, the heat transfer tube groups 103c, 10
The refrigerant flowing in 3d exchanges heat with the air flow indicated by arrow 104 and condenses. In this case, by providing the heat transfer tube group 103d of thin tubes on the gas inflow side (a) of the heat exchanger 101c with fins, the flow velocity of the refrigerant flowing in the tubes in the liquid phase state can be improved and the performance can be improved. It can be achieved.

A third conventional example is Japanese Patent Laid-Open No. 6-174.
A representative drawing of Japanese Patent No. 389 is shown in FIG. FIG. 11 is a side view of the heat exchanger with fins, and the stage pitch P3 of the row of the heat transfer tube group 103f on the gas outflow side (b) of the heat exchanger 101e.
Is longer than the stage pitch P4 of the row of the heat transfer tube group 103e on the gas inflow side (a).

With such a structure, the proportion of the water blocking area 108 of the heat transfer tube group 103f to the opening area of the finned heat exchanger 101e through which the gas 104 flows out can be reduced, so that it is generated when being sucked into the blower 107. The noise generated can be reduced.

A fourth conventional example is Japanese Patent Laid-Open No. 10-21.
Representative drawings of the 3386 publication are shown in FIG. 12 and FIG. FIG. 12 is a perspective view of an independent fin tube heat exchanger showing a part of a finned heat exchanger in detail, and FIG. 13 is a view showing an outdoor unit of a packaged air conditioner to which a fourth conventional example is applied.
The independent fin tube heat exchanger 101g is formed by a heat transfer tube 103g penetrating a plurality of independent fins 102g. Each of the independent fins 102g is configured to be in contact with the lower end portion 101i and the upper end portion 101h, and each of the lower end portion 101i and the upper end portion 101h is configured to intersect at at least one point when they are brought into contact with each other. To do. As a result, the drainage performance can be improved.

[0010]

However, in the structure of the first conventional example, the temperature difference between the adjacent heat transfer tubes 103b is within 0.5 degrees in the two-phase region of the main heat exchanger 101b. , The temperature difference between adjacent heat transfer tubes 103a in the auxiliary heat exchanger 101a in the liquid phase region is 0.5 degrees or more,
The heat loss due to heat conduction between adjacent heat transfer tubes in the auxiliary heat exchanger has a problem that cannot be ignored.

Further, in the configuration of the second conventional example, the heat transfer tube group 1
If a thin tube is simply used without changing the step pitch of 03d, the factor of lowering the fin efficiency is larger than the improvement of the heat transfer coefficient in the tube.
There was a problem that high performance could not be achieved.

Further, in the configuration of the third conventional example, the step pitch P3 of the row of the heat transfer tube group 103f on the gas outflow side (b) is set to be higher than the step pitch P4 of the row of the heat transfer tube group 103e on the gas inflow side (a). By increasing the length, the capacity of the heat exchanger on the gas outflow side is greatly reduced, and the reduced capacity must be compensated for by increasing the air volume, and as a result, it does not contribute to noise reduction. Further, when the step pitch P4 on the gas inflow side (b) is shortened while maintaining the step pitch P3 on the gas outflow side (b), the effect of noise reduction described in the third conventional example cannot be obtained, but When acting as a container, the capacity on the air inflow side can be improved. But,
When it acts as an evaporator, the number of heat transfer tubes increases, and the capacity decreases due to an increase in pressure loss. The third conventional example has such a problem.

Further, in the structure of the fourth conventional example, as shown in FIG. 13, by using the independent fins in all stages, the lower end portion 1
There are many cut portions between 01i and the upper end portion 101h, which disturbs the air flow passing through the heat exchanger, and the resistance of the air flow passing through the heat exchanger is significantly increased as compared with the heat exchanger having no cut portion. Even if the ventilation resistance ratio is good, when it is operated as a condenser having a dry fin surface, the resistance passing through is increased compared to an integral fin without the lower end portion 101i and the upper end portion 101h, and the inside of the blower circuit is increased. When it was installed in a car, it had problems such as an increase in noise level and a decrease in air flow.

The present invention is intended to solve such a conventional problem and suppresses an increase in the area inside the heat transfer tube on the gas inflow side and an increase in the pressure loss inside the tube, and is used for either a condenser or an evaporator of a refrigeration cycle. It is an object of the present invention to provide a heat exchanger with fins that can exhibit high performance even if it is used.

[0015]

In order to solve the above-mentioned problems, the present invention provides a group of fins which are arranged in parallel at a predetermined interval and through which gas flows, and a row which penetrates the fins at a substantially right angle. And a heat transfer tube group through which a fluid flows, and the step pitch between the heat transfer tubes of the gas transfer side heat transfer tube group is smaller than the step pitch between the heat transfer tubes of the gas outflow side heat transfer tube group. ,
And the number of heat transfer tubes in one row of the heat transfer tube group on the gas inflow side,
Which was constructed in the following number in the first column of the tube bank of the gas outlet side, that the tubes in the tube bank of the gas outlet side that increased heat transfer area, condensation capacity and the evaporation capacity with high performance can be achieved Is.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 is a main heat exchanger.
Separated from the converter, it is placed in the supercooling area and the opening area is the main heat exchange
The heat transfer tubes of the auxiliary heat exchanger, which is smaller than the reactor, are configured in an elliptical or flat shape.

With the above arrangement, the distance between the fluid flowing near the center of the heat transfer tube and the tube wall can be reduced.

According to the second aspect of the present invention , the length of the fins between the heat transfer tubes of the heat transfer tube group on the gas inflow side is longer than the step pitch between the heat transfer tubes and the gas outflow side. In the heat transfer tube group, the length of the fins between the heat transfer tubes and the step pitch between the heat transfer tubes are configured to be substantially equal.

According to this structure, the length of the fin portion can be increased while maintaining the stage pitch, heat conduction between the stages of the heat transfer tube can be suppressed, and heat conduction loss between the stages in the heat transfer tube can be reduced. It

According to the third aspect of the present invention , a cutting part or a punching part is provided between the heat transfer pipes and the heat transfer pipes in all the stages of the fins of the row of the heat transfer pipes on the gas inflow side. The part is inclined with respect to the mainstream direction of the air flow.

According to this structure, the loss due to the heat conduction between the stages of the heat transfer tube can be reduced.

Further, in the invention as set forth in claim 4, the heat transfer area of the tube inner surface per unit length in the heat transfer tube on the gas inflow side is set larger than the heat transfer area of the inner surface of the heat transfer tube on the gas outflow side. It was done.

According to this structure, the heat transfer area can be enlarged at the condenser outlet and the evaporator inlet on the gas inflow side. In addition, the expansion of the heat transfer area tends to increase the pressure loss in the tube, but by using it at the condenser outlet and the evaporator inlet part, the expansion of the heat transfer area in the tube while suppressing the decrease of the condensation temperature and the increase of the evaporation temperature Can be achieved.

[0024]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 is a side view showing a heat exchanger with fins according to the first embodiment of the present invention. This finned heat exchanger is an auxiliary heat exchanger 11 located on the gas inflow side (a) of the air flow indicated by arrow 4.
a and a main heat exchanger 11b located on the gas outflow side (b). The auxiliary heat exchanger 11a is composed of a large number of fin groups 12a arranged in parallel at a predetermined interval, and a heat transfer tube group 13a that penetrates the fin groups at a substantially right angle and is arranged in a meandering shape. Further, the main heat exchanger 11b has a large number of fin groups 1 arranged in parallel at a predetermined interval.
2b, and a heat transfer tube group 13b penetrating this fin group at a substantially right angle and arranged in a meandering shape. In the auxiliary heat exchanger 11a, the heat transfer tubes of the heat transfer tube group 13a that are arranged in series are arranged in 6 stages, and the main heat exchanger 11b is arranged in 12 rows in 1 line.
3b is the number of heat transfer tubes in one row or less. That is, the auxiliary heat exchanger 11a includes the heat transfer tube group 13a in one row.
The number of tube stages of the heat transfer tube group 13 in one row of the main heat exchanger 11b.
The number of tubes is smaller than the number of tubes in b, and the heat transfer tube group 1
3a and the plurality of rows of heat transfer tube groups 13b are separated.
In the auxiliary heat exchanger 11a, the step pitch P1 which is the length between the center of the heat transfer tube of the heat transfer tube group 13a and the center of the next heat transfer tube is defined as the step pitch between the heat transfer tubes of the heat transfer tube group 13b of the main heat exchanger 11b. It is shorter than P2. Reference numeral 15 is a branch portion on the inlet side of the heat transfer tube group 13b of the main heat exchanger 11b, and 16 is a branch portion on the outlet side.

The air flow 4 flows through the fin group 12a and the fin group 12b in the direction of the arrow and exchanges heat with the fluid flowing inside the heat transfer tube group 13a and the heat transfer tube group 13b. When mounted on the indoor unit of a separate type air conditioner, it is common to provide several cuts or cuts in the auxiliary or main heat exchanger, and then bend and mount.

In the above structure, when used as a condenser of a refrigeration cycle of an air conditioner, the fluid flowing in the heat transfer tube flows in a gas phase state from the heat transfer tube of the main heat exchanger 11b and is branched as shown by arrow A. The heat transfer tube group 13b is divided into upper and lower parts by the part 15, and becomes a liquid state through a gas-liquid two-phase state by heat exchange with the air flow 4, and then merges again at the branch part 16 to form a cascade of auxiliary heat exchangers 11a. It flows into the heat transfer tubes of the heat tube group 13a and flows out as shown by arrow B.

When acting as an evaporator of a refrigerating cycle of an air conditioner, the fluid flowing in the heat transfer tubes is in a gas-liquid two-phase state, and the heat transfer tube group in which the auxiliary heat exchangers 11a are arranged in tandem as shown by arrow B. After flowing into the heat transfer tube 13a, the branch portion 16 of the main heat exchanger 11b splits the heat transfer tube group 13b up and down to exchange heat with the air flow 4, and then joins again at the branch portion 15 to make an arrow from the heat transfer tube. It flows out like A.

According to this structure, since the step pitch P1 of the heat transfer tube group 13a of the auxiliary heat exchanger 11a is shorter than the step pitch P2 of the heat transfer tube group 13b of the main heat exchanger 11b, the heat transfer area in the heat transfer tube is reduced. It is possible to expand the size of the auxiliary heat exchanger, which can improve the performance of the auxiliary heat exchanger. Therefore, when it acts as a condenser, a large amount of supercooled region in a liquid phase state, which is extremely low in heat transfer performance in the heat transfer tube, can be taken in the auxiliary heat exchanger 11a, which results in good heat transfer performance in the tube. Many two-phase states can be taken in the main heat exchanger 11b, the heat exchange capacity can be increased, and the finned heat exchanger can be improved in performance. Further, when it is operated as an evaporator, the number of stages of the heat transfer tubes in one row of the auxiliary heat exchanger 11a is set to be smaller than the number of stages in one row of the heat transfer tube group 13b of the main heat exchanger, so that the pipe internal pressure is reduced. It is possible to suppress an increase in loss and improve the evaporation capacity.

(Second Embodiment) FIG. 2 is a side view showing a heat exchanger with fins according to a second embodiment of the invention. In this finned heat exchanger, the tube diameter of the heat transfer tubes in the heat transfer tube group of the auxiliary heat exchanger is made smaller than the tube diameter of the heat transfer tube group of the main heat exchanger.
Since it is only different from the above, the other parts having the same configurations and effects are denoted by the reference numerals, and detailed description thereof will be omitted.
The different parts will be mainly described.

Reference numeral 21a is an auxiliary heat exchanger, and 21b is a main heat exchanger. Then, the auxiliary heat exchanger 21a uses the outer diameter d of the heat transfer tubes in the heat transfer tube group 23a as the main heat exchanger 21b.
It is configured to be smaller than the outer diameter D of the heat transfer tubes in the heat transfer tube group 23b. P1 is a step pitch which is the length between the heat transfer tube center of the heat transfer tube group 23a of the auxiliary heat exchanger 21a and the next heat transfer tube center, and is shorter than the step pitch P2 of the heat transfer tube group 23b of the main heat exchanger 21b. Configured. Further, the auxiliary heat exchanger 21a is configured such that the number of heat transfer tubes of the heat transfer tube group 23a is equal to or less than the number of heat transfer tubes in one row of the heat transfer tube group 23b of the main heat exchanger 21b. 22a and 22b are auxiliary heat exchangers 21a
In the fin group of the main heat exchanger 21b, 25 and 26 are branch portions of the heat transfer tube group 23b. Reference numeral 4 is an arrow indicating the main flow direction of the air flow.

When used as a condenser of the refrigerating cycle of the air conditioner with the above-mentioned structure, the fluid flowing in the heat transfer tube is in the vapor phase as shown in the arrow A in the main heat exchanger 21b, as in the first embodiment. It flows into the heat pipe and is branched from the branch portion 25 to the upper and lower sides of the heat transfer tube group 23b, and becomes a liquid state through a gas-liquid two-phase state by heat exchange with the air flow 4, and merges again at the branch portion 26 to form the auxiliary heat exchanger 21a. Flows into the heat transfer tubes of the heat transfer tube group 23a in a row and flows out as indicated by arrow B.

Further, when acting as an evaporator of a refrigeration cycle of an air conditioner, the fluid flowing in the heat transfer tubes is in a gas-liquid two-phase state, and a group of heat transfer tubes in which auxiliary heat exchangers 21a are arranged in series as shown by arrow B. 23a, the heat transfer tubes of the main heat exchanger 21b are further branched to the upper and lower parts of the heat transfer tube group 23b at the branch portion 26 of the heat transfer tube to perform heat exchange with the air flow 4, and then joined again at the branch portion 25. It flows out from the heat transfer tube as shown by arrow A.

According to this structure, the stage pitch P1 of the heat transfer tube group 23a of the auxiliary heat exchanger 21a is shorter than the stage pitch P2 of the heat transfer tube group 23b of the main heat exchanger 21b, and the heat transfer of the auxiliary heat exchanger 21a is performed. Heat transfer tube outer diameter d in the heat tube group 23a
Is a thin tube smaller than the outer diameter D of the heat transfer tube in the heat transfer tube group 23b of the main heat exchanger 21b, so that the fin efficiency is prevented from being reduced due to the thinning of the tube, and the heat transfer area in the heat transfer tube is expanded. The performance of the auxiliary heat exchanger 21a can be improved by improving the heat transfer performance by increasing the flow velocity of the fluid flowing in the heat pipe. Therefore, when acting as a condenser, a large amount of supercooled region in a liquid phase state, which is extremely low in heat transfer performance in the pipe, can be taken in the auxiliary heat exchanger 21a, whereby two-phase excellent heat transfer performance in the pipe is achieved. Many states can be taken in the main heat exchanger 21b, the heat exchange capacity can be increased, and the finned heat exchanger can be improved in performance. Further, when the auxiliary heat exchanger 21a is operated as an evaporator, the number of stages of heat transfer tubes in one row of the auxiliary heat exchanger 21a is 1 of that of the main heat exchanger 21b.
By setting the number of stages less than the number of heat transfer tubes in the row,
It is possible to suppress an increase in pressure loss in the pipe and improve the evaporation capacity.

(Embodiment 3) FIG. 3 is a sectional view showing an auxiliary heat exchanger portion of a heat exchanger with fins according to the invention of Embodiment 3. This finned heat exchanger is different from the first embodiment only in that the heat transfer tubes in the heat transfer tube group of the auxiliary heat exchanger have a flat shape. Therefore, the other parts having the same structure and effect are denoted by the reference numerals. The detailed description will be omitted, and different parts will be mainly described.

Reference numeral 31a is an auxiliary heat exchanger. In the auxiliary heat exchanger 31a, the heat transfer tubes in the heat transfer tube group 33a are formed in a flat shape. 32a is an auxiliary heat exchanger 31a
Is a fin. 4 is the mainstream air flow direction.

According to the above construction, when used as a condenser or an evaporator of the refrigeration cycle of the air conditioner, the fluid flows in the heat transfer tube and exchanges heat with the air flow 4 as in the first embodiment.
The fluid near the center flowing in the heat transfer tube exchanges heat with the inner wall of the heat transfer tube due to heat conduction and convection in the fluid, especially in the liquid phase region of the condenser, and passes through the heat exchanger through the fins outside the heat transfer tube. Exchanges heat with the airflow. By making the heat transfer tubes of the heat transfer tube group 33a of the auxiliary heat exchanger 31a flat, the fluid near the center of the fluid flowing in the tube can shorten the distance from the inner wall of the tube,
The amount of heat exchange by heat conduction can be increased. In addition, the flat shape reduces the hydraulic diameter, increases the Reynolds number, and promotes turbulent flow, which can further improve the performance of the auxiliary heat exchanger.

When the auxiliary heat exchanger 31a is operated as an evaporator, the number of stages of the heat transfer tubes in one row of the auxiliary heat exchanger 31a is smaller than the number of stages in one row of the main heat exchanger, so that the pressure loss in the tubes is reduced. It is possible to suppress the increase in the evaporation rate and improve the evaporation capacity.

The same effect can be obtained by using an elliptical shape instead of the flat shape of the heat transfer tubes of the heat transfer tube group 33a of the third embodiment.

(Embodiment 4) FIG. 4 (a) is a perspective view showing a heat exchanger with fins according to the invention of Embodiment 4, and FIG. 4 (b) is a front view. In this heat exchanger with fins, the fin length between the heat transfer tubes of the heat transfer tube group on the gas inflow side is longer than the step pitch between the heat transfer tubes, and the heat transfer tube of the heat transfer tube group on the gas outflow side is Only the fins between the heat transfer tubes and the step pitches between the heat transfer tubes are configured to have substantially the same length, which is the only difference from the first embodiment. Therefore, other parts having the same configuration and operational effect are denoted by reference numerals. The detailed description will be omitted and different parts will be mainly described.

Reference numeral 41a is an auxiliary heat exchanger, and 41b is a main heat exchanger. 42a and 42b are auxiliary heat exchangers 4, respectively
1a and a fin group of the main heat exchanger 41b. The fin group 42a of the auxiliary heat exchanger 41a is formed in a wavy shape. 43a and 43b are auxiliary heat exchangers 41a, respectively.
And a heat transfer tube group of the main heat exchanger 41b. Also, P1 and P
2 is a step pitch of the length between the center of the heat transfer tubes of the heat transfer tube group 43a of the auxiliary heat exchanger 41a and the heat transfer tube group 43b of the main heat exchanger 41b and the center of the next heat transfer tube. d is the outer diameter of the heat transfer tubes of the heat transfer tube group 42a of the auxiliary heat exchanger 41a, and D is the outer diameter of the heat transfer tubes of the heat transfer tube group 42b of the main heat exchanger 41b. Then, in the auxiliary heat exchanger 41a on the gas inflow side (a), the length L1 + L2 + L3 + L4 of the corrugated fins between the heat transfer tubes of the heat transfer tube group 42a is made longer than the step pitch P1 between the heat transfer tubes. In the main heat exchanger 41b on the gas outflow side (b), the length of the fins between the heat transfer tubes of the heat transfer tube group 43b and the step pitch P2 between the heat transfer tubes are set to be substantially equal. It is a thing.

According to the above construction, when used as the condenser of the refrigeration cycle of the air conditioner, the fluid flowing in the heat transfer tube flows in from the main heat exchanger 41b side and the auxiliary heat exchanger 41a as in the first embodiment. Spill to the side. Also, when used as an evaporator, it flows in from the auxiliary heat exchanger 41a side and flows out to the main heat exchanger 41b side as in the first embodiment. When acting as a condenser, the heat transfer tube group 4 of the main heat exchanger 41b
The fluid in 3b is in the two-phase state in the saturation region, and the heat transfer tube group 4
The temperature difference between the stages of 3b is about 0.2 to 0.3 degrees, and there is almost no temperature difference. On the other hand, the fluid in the heat transfer tube group 43a of the auxiliary heat exchanger 41a is in a liquid phase state, and the temperature difference between the heat transfer tubes between the stages of the heat transfer tube group 43a is large.

However, in the invention of the fourth embodiment, the heat conduction loss due to the temperature difference between the heat transfer tubes of the heat transfer tube group 43a of the auxiliary heat exchanger 41a and the stages of the heat transfer tubes is reduced by the fin length L1 + L between the heat transfer tubes.
Since 2 + L3 + L4 is made longer than the stage pitch P1 between the heat transfer tubes, the heat transfer loss in the auxiliary heat exchanger 41a is reduced, and the main heat exchanger 41b in which the heat transfer loss due to the temperature difference between the stages is small is the heat transfer tube. The fin length between the heat transfer tubes of the group 43b and the step pitch P2 of the heat transfer tubes are substantially equal to each other to maintain the fin efficiency, so that the finned heat exchanger can have high performance.

When operated as an evaporator, the number of tube stages of the heat transfer tube group in one row of the auxiliary heat exchanger 41a is smaller than that of the heat transfer tube group in one row of the main heat exchanger 41b. By doing so, it is possible to suppress an increase in pressure loss in the pipe and improve the evaporation capacity.

The effect of thinning the heat transfer tubes in the heat transfer tube group of the auxiliary heat exchanger 41a and the flat shape is the same as in the first embodiment.
Further, it has the same effect as the above.

(Embodiment 5) FIG. 5 is a sectional view of an auxiliary heat exchanger in a heat exchanger with fins according to the invention of Embodiment 5. This heat exchanger with fins is different from the first embodiment in that the fins between the heat transfer tubes of the heat transfer tube group on the gas inflow side are provided with a cutting portion or a punching portion that is inclined with respect to the air flow direction. Therefore, other parts having the same configuration and operational effect are denoted by the same reference numerals, detailed description thereof will be omitted, and different parts will be mainly described.

Reference numeral 51a is an auxiliary heat exchanger, which is composed of a fin group 52a arranged in parallel with a space therebetween and a heat transfer tube group 53a arranged in a meandering pattern penetrating the fin group 52a at a right angle. 57
Is a linear cut portion (also referred to as a cut portion) which is provided in the fin between the heat transfer tubes of the heat transfer tube group 53a so as to be inclined with respect to the air flow direction shown by the arrow 4. θ is notch 5
7 is the inclination angle between the airflow 4 and the mainstream direction of the airflow 4.

According to the above construction, when used as the condenser of the refrigeration cycle of the air conditioner, the fluid flowing in the heat transfer tube flows in from the main heat exchanger side and the auxiliary heat exchanger 51a side, as in the first embodiment. Outflow to. Also, when used as an evaporator, as in the first embodiment, it flows in from the auxiliary heat exchanger 51a side and flows out to the main heat exchanger side. When acting as a condenser, the fluid in the heat transfer tube of the main heat exchanger is in a two-phase state in the saturation region, and the temperature difference between the heat transfer tube and the tube stages of the heat transfer tube is 0.
There is almost no temperature difference between 2 and 0.3 degrees. On the other hand, the fluid in the heat transfer tube group 53a of the auxiliary heat exchanger 51a is in a liquid phase state, and the temperature difference between the heat transfer tubes and the tube stages of the heat transfer tubes is large.

However, in the invention of the fifth embodiment, the heat conduction loss due to the temperature difference between the heat transfer tubes in the auxiliary heat exchanger 51a and the tube stages of the heat transfer tubes is caused by the arrow 4 provided on the fins between the heat transfer tubes.
The linear cut portion 5 inclined with respect to the air flow direction shown by
7, the finned heat exchanger can be improved in performance.

When the auxiliary heat exchanger 51a is operated as an evaporator, the number of stages of heat transfer tubes in one row of the auxiliary heat exchanger 51a is set to be smaller than the number of tubes in one row of the main heat exchanger, so that the internal pressure of the tubes is reduced. The increase in loss is suppressed, the evaporation capacity is improved, and the cut portion 57 is provided with an inclination angle θ with respect to the mainstream direction of the air flow so that condensed water adhering to the fin surface is not retained by the cut end surfaces 58a and 58b. It can be discharged, and an increase in ventilation resistance when wet can be suppressed.

Although the notch 57 is a straight line in the fifth embodiment, the same effect can be obtained even if the notch 57 is curved or serrated. Further, the same effect can be obtained by using a thin cutoff portion (also referred to as a punched portion) instead of the cut portion. Further, the notch 57 of the fifth embodiment has an end face 58.
Although a and 58b are extended to the side of the heat transfer tubes of the heat transfer tube group 53a, they may end before the heat transfer tubes of the heat transfer tube group 53a.

(Sixth Embodiment) FIG. 6 is a sectional view of an auxiliary heat exchanger in a heat exchanger with fins according to the sixth embodiment of the present invention. In this finned heat exchanger, the fins between the heat transfer tubes of the heat transfer tube group of the auxiliary heat exchanger are provided with a plurality of cut-and-raised parts or irregularities substantially at right angles to the mainstream direction of the airflow in the above-mentioned embodiment. Since it is only different from 1, the other parts having the same configuration and action and effect are denoted by reference numerals, detailed description thereof will be omitted, and different parts will be mainly described.

Reference numeral 61a denotes an auxiliary heat exchanger, which is composed of a fin group 62a arranged in parallel with a gap and a heat transfer tube group 63a penetrating the fin group 62a at a right angle and arranged in a meandering shape. 69
Is a plurality of cut-and-raised parts provided in the fins between the heat transfer tubes of the heat transfer tube group 63a of the auxiliary heat exchanger 61a substantially at right angles to the mainstream airflow direction shown by arrow 4.

According to the above construction, when used as the condenser of the refrigeration cycle of the air conditioner, the fluid flowing in the heat transfer tubes flows in from the main heat exchanger side and the auxiliary heat exchanger 61a side as in the first embodiment. Outflow to. Also, when used as an evaporator, it flows in from the auxiliary heat exchanger 61a side and flows out to the main heat exchanger side as in the first embodiment. And the auxiliary heat exchanger 6
The heat transfer coefficient on the air side is promoted by the boundary layer leading edge effect due to the fin cut-and-raised 69 between the heat transfer tubes of the heat transfer tube group 63a of 1a, and it is used in combination with the configurations of the inventions of Examples 1 to 5 described above. By doing so, each effect is further promoted.

Although the cut-and-raised 69 is a straight line in the sixth embodiment, the same effect can be obtained even if the cut-and-raised part 69 is a curved line or a sawtooth shape. Further, if the shape is not a cut, but an uneven shape, it is possible to promote heat transfer, although the action is inferior to the cut and raised shape.

(Embodiment 7) FIG. 7 (a) is an enlarged sectional view of a heat transfer tube of an auxiliary heat exchanger in a heat exchanger with fins according to the invention of Embodiment 7, and FIG. 7 (b) is a main heat exchanger. It is an expanded sectional view of a heat transfer tube. In this heat exchanger with fins, the heat transfer area of the inner surface of the heat transfer tubes of the heat transfer tube group of the auxiliary heat exchanger per unit length is calculated from the heat transfer area of the inner surface of the heat transfer tube of the main heat exchanger. Since the point of enlargement is the same as that of the first embodiment, other parts having the same configuration and operational effect are denoted by the same reference numerals, detailed description thereof will be omitted, and different parts will be mainly described.

Reference numeral 70a denotes an inner peripheral surface of a large number of grooves formed on the inner surface of the heat transfer tubes forming the heat transfer tube group 73a of the auxiliary heat exchanger, and has a mountain height of h1. The groove inner peripheral surface 70a has a heat transfer area of the tube inner surface per unit length of the heat transfer tube lower than the mountain height h1 on the inner surface of the heat transfer tube forming the heat transfer tube group 73b of the main heat exchanger. The heat transfer area is set to be larger than the heat transfer area of the inner surface of the heat transfer tube in which a large number of groove inner peripheral surfaces 70b having the mountain height h2 are formed.

According to the above construction, when used as the condenser of the refrigeration cycle of the air conditioner, the fluid flowing in the heat transfer tubes flows in from the main heat exchanger side using the heat transfer tube group 73b, as in the first embodiment. , To the auxiliary heat exchanger side using the heat transfer tube group 73a. Also, when used as an evaporator, it flows in from the auxiliary heat exchanger side using the heat transfer tube 73a and flows out to the main heat exchanger side using the heat transfer tube 73b as in the first embodiment. Further, the heat transfer tube group 73a has a mountain height h of the groove inner peripheral surface 70a.
1 is set higher than the mountain height h2 of the groove inner peripheral surface 70b of the heat transfer tube group 73b, the groove inner peripheral surface 70b of the heat transfer tube group 73b is
By making it longer, the heat transfer area on the inner surface of the heat transfer tube can be increased to improve the performance of the auxiliary heat exchanger. On the other hand, increasing the peak height of the groove inner peripheral surface 70a of the heat transfer tube group 73a may increase the pressure loss in the tube, but the auxiliary heat exchanger is in a liquid phase state, has a large density, and has a high flow rate. Since it becomes slower, it can be said that there is almost no effect of pressure loss.

When used as an evaporator, by using the heat transfer tube group 73a of the auxiliary heat exchanger on the evaporator inlet side, the increase in the pipe pressure loss is only a part on the inlet side, and the increase of the evaporation temperature is caused. It is possible to suppress, and it is possible to make use of the improvement of the heat transfer performance due to the increase of the mountain height h1, and it is possible to improve the evaporation capacity.

In addition, the invention of Example 7 is described in Examples 1-2.
By combining the inventions of Embodiments 4 to 6, it is possible to further improve the performance of the heat exchanger with fins .

[0061]

As is apparent from the above embodiments, the present invention
The invention according to claim 1 is a separate body from the main heat exchanger and is supercooled.
Auxiliary heat exchanger located in the rejection area and having an opening area smaller than that of the main heat exchanger.
The heat transfer tubes of the heat exchanger tube group are formed into an elliptical or flat shape, and the distance between the fluid flowing near the center of the heat transfer tubes and the tube wall is reduced to improve heat transfer coefficient and improve performance. Can be achieved.

In the invention according to claim 2, the length of the fin between the heat transfer tubes of the heat transfer tube group on the gas inflow side is longer than the step pitch between the heat transfer tubes, and the heat transfer tube on the gas outflow side is provided. The length of the fins between the heat transfer tubes of the group and the step pitch between the heat transfer tubes are configured to be substantially equal, and the length of the fin portion can be increased while maintaining the step pitch. It is possible to suppress heat conduction and to improve performance by reducing heat conduction loss between heat transfer tubes.

Further, in the invention according to claim 3, the fins between the heat transfer tubes of the heat transfer tube group on the gas inflow side,
A cutting part or punching part with a predetermined length is provided, and the cutting part or punching part is inclined with respect to the main flow direction of the airflow, and loss due to heat conduction between the heat transfer tubes can be reduced, and high performance Can be realized.

Further, in the invention according to claim 4, the heat transfer area of the inner surface of the heat transfer tube of the heat transfer tube group of the gas inflow side per unit length of the heat transfer tube of the heat transfer tube group of the gas outflow side The heat transfer area is made larger than that of the heat transfer area. For example, the heat transfer area can be increased at the condenser outlet and the evaporator inlet portion, which are used in the refrigeration cycle and on the gas inflow side, so that high performance can be achieved. On the other hand, increasing the heat transfer area on the inner surface of the heat transfer tube tends to increase the pressure loss in the tube, but by using it at the condenser outlet and the evaporator inlet part, it is possible to prevent the condensation temperature from decreasing and the evaporation temperature from increasing. Higher performance can be achieved by expanding the heat transfer area.

[Brief description of drawings]

FIG. 1 is a side view of a heat exchanger with fins according to a first embodiment of the present invention.

FIG. 2 is a side view of the heat exchanger with fins showing the second embodiment.

FIG. 3 is a sectional view of an auxiliary heat exchanger in the heat exchanger with fins according to the third embodiment.

FIG. 4A is a perspective view of a main part of a heat exchanger with fins showing the fourth embodiment, and FIG. 4B is a front view of a main part of an auxiliary heat exchanger showing the fourth embodiment.

FIG. 5 is a sectional view of an auxiliary heat exchanger in the heat exchanger with fins according to the fifth embodiment.

FIG. 6 is a sectional view of an auxiliary heat exchanger in the heat exchanger with fins according to the sixth embodiment.

7A is a sectional view of a heat transfer tube of an auxiliary heat exchanger in the finned heat exchanger according to the seventh embodiment, and FIG. 7B is a main heat exchanger in the finned heat exchanger according to the seventh embodiment. Cross section of heat transfer tube

FIG. 8 is a perspective view of a heat exchanger with fins showing a first conventional example.

FIG. 9 is a side view of the heat exchanger with fins.

FIG. 10 is a perspective view of a heat exchanger with fins showing a second conventional example.

FIG. 11 is a side view of a finned heat exchanger showing a third conventional example.

FIG. 12 is a perspective view of a heat exchanger with independent fins showing a fourth conventional example.

FIG. 13 is a top view of an outdoor unit of an air conditioner equipped with a heat exchanger with independent fins showing a fourth conventional example.

[Explanation of symbols]

4 Main air flow direction (a) Gas inflow side (b) Gas outflow side 11a, 21a, 31a, 41a, 51a, 61a Auxiliary heat exchanger 11b, 21b, 41b Main heat exchanger 13a, 23a, 33a, 43a, 53a, 63a, 7
3a Heat transfer tube group 13b, 23b, 43b, 73b of auxiliary heat exchanger Heat transfer tube group 12a, 22a, 32a, 42a, 52a, 62a of main heat exchanger Fin group 13b, 23b, 32b, 42b of auxiliary heat exchanger Main Fin group 57 of heat exchanger Cut portion 69 Cut and raised fin surface between heat transfer tubes 70a Inner groove surface 70b of heat transfer tube of auxiliary heat exchanger d Inner groove surface of heat transfer tube of main heat exchanger d Auxiliary heat exchanger Outer diameter D of heat transfer tube of main heat exchanger L1, L2, L3, L4 Fin length between heat transfer tubes P1 Stage pitch of heat transfer tube of auxiliary heat exchanger P2 Stage of heat transfer tube of main heat exchanger Pitch θ Main flow direction and inclination angle of notch

Continuation of front page (56) References JP-A-8-313049 (JP, A) JP-A-5-79654 (JP, A) JP-A-6-307738 (JP, A) JP-A-58-138994 (JP , A) Japanese Patent Laid-Open No. 10-339587 (JP, A) Jitsukō Sho 50-37085 (JP, Y1) (58) Fields investigated (Int.Cl. ⁷ , DB name) F25B 39/00-39/04 F28F 1/00-1/44

Claims (4)

(57) [Claims] 1. A gas turbine is installed in parallel at a predetermined interval, with a gas between them.
And the fins that flow
Are arranged in a row and have a group of heat transfer tubes through which the fluid flows,
Separated from the heat exchanger, it is placed in the supercooled area and the opening area is the main heat.
A heat exchanger with fins , characterized in that the heat transfer tube of the auxiliary heat exchanger smaller than the exchanger is formed into an elliptical or flat shape. 2. A gas is provided in parallel at predetermined intervals, with a space between them.
And the fins that flow
Lined up and equipped with a group of heat transfer tubes through which the fluid flows,
When used as a compressor, the fluid in the supercooled liquid state flows inside.
The length of the fins between the heat transfer tubes of the heat transfer tube group on the gas inflow side is longer than the step pitch between the heat transfer tubes, and the length of the fin between the heat transfer tubes of the heat transfer tube group on the gas outflow side that is configured to substantially equal the length of step pitch between Sato heat transfer tube
Characteristic heat exchanger with fins. 3. Gas is provided in parallel with a predetermined interval in parallel.
And the fins that flow
And a heat transfer tube group in which the fluid flows inside,
Functions as an evaporator or condenser and is used as a condenser
At this time, the fins between the heat transfer tubes of the heat transfer tube group on the gas inflow side through which the fluid in the supercooled liquid state flows are provided with cutting portions or punching portions of a predetermined length, and the cutting is performed. A heat exchanger with fins , characterized in that the part or the punched part is inclined in a direction in which the part or the punched part is lowered toward the gas outflow side of the air flow. Wherein the heat transfer area of the tube surface per unit length of the heat transfer tube of the tube bank of the gas inlet side, that was larger construction than the heat transfer area of the heat transfer tube surface of the tube bank of the gas outflow side Features and
The heat exchanger with fins according to any one of claims 1 to 3 .