JPS61285391A - Heat exchanger - Google Patents

Abstract

PURPOSE:To enable the improvement of heat transfer performance by a method wherein first flow path is formed in the fine tubes of the group of fine tubes, in which a plurality of fine tubes are neighbored and connected, and a space between the fine tubes while second flow path is formed in the outer periphery of the groups of fine tubes, in the heat exchanger for car cooler or the like. CONSTITUTION:The first flow path, through which fluid B flows, is formed by the groups 1 of fine tubes, in which the round tubes, made of aluminum, copper or the like, are arranged in checkerboard pattern and are bonded or welded with each other. On the other hand, the second flow path, through which the fluid A flows, is formed by the outer walls of the group 1 of fine tubes and side wall plates 2. The fluid B flows through the fine tubes and spaces between the fine tubes while exchanging the heat thereof between the fluid A. According to this method, the heat transfer performance may be improved by the increase of heat transfer area for direct heat exchange between the fluid A, flowing through the second flow path, and the group 1 of fine tubes whereby the heat exchanger may be compacted.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a heat exchanger used in, for example, car coolers, room air conditioners, refrigerators, and the like.

Conventional technology FIG. 3 shows a conventional heat exchanger in which a flow path for fluid B is formed by bending a flat tube 22, and fins 21 formed by bending a thin plate are inserted into the straight portion of the flat tube. It is composed of
The contact portion between the fin 21 and the flat tube 22 is fused and joined by brazing, soldering, or the like. Generally fin 2
1 has fins such as louvers and slits to improve heat transfer performance.

Problems to be Solved by the Invention It is difficult to accurately process the height and pitch of the bent portion of the fin 21, and if the fin height varies, a bonding failure occurs and the thermal resistance between the tube 22 and the fin 210 increases. increases,
Heat transfer performance is significantly reduced.

Fin processing such as louvers and slits is not the optimal shape for heat transfer performance due to the bending process. In order to improve heat transfer performance, it is possible to reduce the fin pitch, but this poses problems in terms of bending accuracy and buckling strength of the fins 21.

Means for Solving the Problem A first flow path was formed by the spaces within and between the thin tubes of a group of thin tubes in which a plurality of thin tubes were adjacent and joined, and a second flow path was formed around the outer periphery of the group of thin tubes. Heat exchanger.

Operation Fluid B flowing through the first channel passes through the thin tube group in the tube axis direction. At this time, fluid B not only flows inside the capillary but also flows within the gap formed by adjacent capillaries.

The fluid flowing through the second flow path flows within the flow path formed by the gap between the outer circumferential walls of the adjacent thin tube groups. At this time, there is no object intervening between the fluid A and the group of thin tubes, and the contact surface between the two increases.

Example FIG. 1 is a partial perspective view showing one embodiment of the present invention.

The thin tube group 1 forming the first flow path includes circular tubes made of aluminum, copper, etc. arranged in a grid pattern, and the circular tubes are bonded or welded to each other. The second flow path is formed by the outer wall of the thin tube group 1 and the side wall plate 2. If you use a circular tube,
Compared to the conventional example in which the fins 21 are used at the same pitch as the pipe diameter, the heat transfer area of unit length l in the flow direction of the fluid B is about three times as large. Therefore, the same heat transfer area as the conventional one can be secured, and the heat exchanger can be made more compact.

Furthermore, the heat transfer will be compared with the conventional example. The fin 2
1 is a parallel plate model, the fin pitch is 1 mm, the fin width is 2 oInIn, the fluid BQ is air, and its velocity is f 11II
When calculated as /S, the average or cell number is 7.96. In the case of a circular pipe, if the pipe diameter is 1 city, the average number of cells is 4
．． 36, but since the equivalent diameter of a circular tube is half that of a parallel plate, the heat transfer coefficient becomes large. Also, according to calculations, the heat transfer in the gap formed by the outer surface of the circular tube is even better than that in the inner surface. In addition, in the conventional example, there is a channel wall between the fluid man and the fins, but in this embodiment, heat is directly transmitted from the fluid man to the thin tube group, and the contact surface between the fluid man and the thin tube group increases. Furthermore, heat transfer performance is improved. FIG. 2 shows the case where a part of the header is provided. A partition plate 3 is provided to prevent fluid leakage to the outside. Further, in this embodiment, the circular tubes are arranged in a grid pattern, but it is also possible to arrange them in a staggered manner to form a group of circular tubes.

Effects of the Invention The heat exchanger according to the present invention has the above-described configuration, and the heat transfer performance is improved by direct heat exchange between the fluid flowing through the second flow path and the group of thin tubes, and by increasing the heat transfer area. This makes it easier to make the heat exchanger more compact.

[Brief explanation of drawings]

1 and 2 are perspective views of a heat exchanger showing an embodiment of the present invention, and FIG. 3 is a perspective view of a conventional heat exchanger. 1... - Thin tube group, 2... Side wall plate, 3...
...Partition plate, 4...Part of the header.

Claims (1)

[Claims] A heat exchanger in which a first flow path is formed by spaces within and between the thin tubes of a group of thin tubes in which a plurality of thin tubes are joined together, and a second flow path is formed around the outer periphery of the group of thin tubes.