JPS61268987A - Heat exchanger - Google Patents

Abstract

PURPOSE:To improve a heat transfer coefficient by a method wherein respective through holes for heat transfer fluid, flowing from expanded flow path toward narrowed flow path, are formed positively with burring sections respectively at the outlet sides thereof. CONSTITUTION:The sectional area of the expanded flow path 4 is larger than the same of the narrowed flow path 5 and the flow speed of the fluid, flowing through the expanded flow path 4, becomes smaller than the same of the fluid, flowing through the narrowed flow path 5, therefore, a part of the fluid flows from the expanded flow path 4 into the narrowed flow path 5 through the through holes 2 equipped with the burring sections 2a as shown by the arrow signs in the diagram. The burring sections are formed at the outlet side of the heat transfer fluid, therefore, the flow of the fluid may be induced smoothly. Temperature boundary layer is thinned by the inducing inflow of the heat transfer fluid and, therefore, the heat transfer coefficient may be improved. Further, the surface area of the burring sections is added to the surface area of the heat exchanger, therefore, reduction of heat exchanging area in case the heat exchanger is equipped with only the through holes may be prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a heat exchanger used in an air conditioner, and in particular to improving the heat dissipation performance of a heat exchanger plate that forms the main body of a heat exchanger fin device. Regarding.

[Conventional technology]

Figures 4, 5, and 6 are a sectional view showing the main parts of the heat exchanger disclosed in Japanese Patent Application No. 59-2640117, which forms the basis of this invention, and a perspective view and a sectional view showing the heat transfer fin device thereof. In Figure 1, -C (1aX1bX1c') is a heat exchanger plate each having a large number of through holes (2).

As shown in the figure, a plurality of these are arranged side by side in a stacked manner at predetermined intervals, and between them, as shown in Fig. 6, they form branch channels (A1) (A2) of fluid canals for cooling the outside air, etc. ing. (3) is each of the above heat exchanger plates (1a) (1bX1c)
The bending walls are formed repeatedly at the same pitch on each of the heat exchanger plates, and this allows the cross-sectional area of the flow path to vary periodically in the flow direction of the fluid between the heat exchanger plates when they are installed side by side. Enlarged channels (4) and narrow channels (5) are alternately formed back to back. Further, (6) in FIG. 4 shows a distribution pipe for refrigerant, etc.

Since the heat transfer fin device in the conventional heat exchanger is configured as described above, the heat transfer plates (1a) (1b) (1
When fluid (A) is passed between C), a pressure difference is generated between the enlarged channel (4) and the narrow channel (5), which are placed back to back.

The flow direction of the fluid passing through the branch channel (AIXA2) does not change, and a portion of the fluid flows through the aforementioned large number of through holes (2) at back-to-back locations, thereby causing each heat exchanger plate (1a) (
1b) It is developed and formed along the surface of (1c). This allows the so-called temperature boundary layer to be made thinner, making it possible to obtain a heat transfer fin device with extremely high heat transfer coefficient.

[Problem that the invention seeks to solve]

As mentioned above, although it is expected that the heat transfer coefficient will improve with the conventional type, each heat transfer plate has a large number of through holes, so the heat exchange area decreases by the number of through holes. I will do it. This invention focuses on this point and aims to avoid reducing the heat exchange area as much as possible without reducing the improvement in heat transfer coefficient due to the opening of one through hole.

[Means for solving problems]

In the case of this invention, a burring portion is actively formed on the exit side of each of the through holes of the heat transfer fluid flowing from the enlarged channel to the narrow channel while the fluid is flowing into each branch channel. ing.

[Effect]

In the case of this invention, since a burring part is formed in the through hole of each heat transfer plate, the heat exchange area increases by the area of this burring part, and each burring part is formed through the through hole through which the heat transfer fluid passes. Since it is formed on the exit side of the hole and promotes its flow, the heat transfer coefficient by this heat transfer fluid can be improved in a counterproductive manner.

〔Example〕

FIG. 1 is a perspective view showing an embodiment of the heat exchanger of the present invention, and the same parts as in the conventional one are indicated by the same reference numerals. A plurality of heat transfer plates (1aX1b) (Ic
) is characterized in that it is composed of a laminate. In addition, (6) in the figure is a refrigerant, for example, arranged so as not to prevent the cooling fluid (4) such as outside air from flowing between the laminated heat transfer plates (Ig) (1b) (1c). It is a distribution pipe. FIG. 2 shows each heat exchanger plate (1a) (1b) of the present invention described above.
) (1c), the above-mentioned burring part ( 2a) of the through hole J with the corresponding burring part (
The formation direction of 2a) is inward when viewed from the narrow channel (5) of the branch channel (AI) (A2), and the enlarged channel (4).
It is arranged so that it is on the outside when viewed from above.

In the above configuration, if the fluid flowing through the branch channel (AIXA2) is considered in the X-X cross section where the narrow channel (5) and the enlarged channel (4) are adjacent to each other back to back, then the enlarged channel (
Since the cross-sectional area of 4) is larger than the cross-sectional area of the narrow channel (5), the flow velocity of the fluid flowing through the enlarged channel (4) is lower than that of the narrow channel (5) at that part. force, narrow flow path (5
) and the enlarged channel (4), and as a result, a portion of the fluid flows from the enlarged channel (4) to the narrow channel (5) through the through hole (2a) with the burring portion (2a). 2) and flows in as shown by the arrow in the figure. In addition, since the formation direction of the burring portion (2a) is located on the exit side of the heat transfer fluid, the flow of the heat transfer fluid is thereby smoothly induced. This is useful for thinning the temperature boundary layer by suctioning and inflowing the heat transfer fluid, thereby increasing the heat transfer efficiency. In addition, since the surface area of the burring portion is added to the surface area of the heat exchanger, it is possible to prevent the heat exchange area of the heat exchanger from decreasing due to a simple through hole.

[Effects of the Invention] As described above, in the heat exchanger of the present invention, a burring portion is actively formed in the through hole provided in each heat transfer plate, so that the heat exchange area is increased only by this burring portion. It is said that since it is provided on the exit side of the burring s1 through which the heat transfer fluid flows, it is said that by promoting the generation action, a further heat transfer promotion effect can be expected, and the heat transfer coefficient will be improved. It is effective.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an embodiment of the heat exchanger of the present invention;
Figure 2 is a front view of the heat transfer fin device in Figure 1;
The figure is an enlarged ut-m sectional view of FIG. Fig. 4 is a partially enlarged cross-sectional view showing an example of a conventional heat exchanger, Fig. 5 is a perspective view showing a combined state of the heat exchanger plates shown in Fig. 4, and Fig. 6 is a cross-sectional view of the one shown in Fig. 5. FIG. 2 is an explanatory diagram of the main parts shown in In the figure, (4) is the fluid, (AI) (A2) is the branch channel * (1a) (1b) (1C) is the heat transfer plate, (2) is the through hole, (2a) is the burring part, (4) 51 indicates an enlarged channel, and 51 indicates a narrow channel. In other figures, the same reference numerals indicate the same parts.

Claims (1)

[Claims] It consists of a plurality of heat exchanger plates that are placed opposite each other so that the cross-sectional areas of the branch channels between them differ periodically along the flow direction of the fluid flowing between them, and each of which has a large number of through holes. , in which a pressure difference between an enlarged channel and a narrow channel formed back to back in each branch channel generates a heat transfer fluid that passes through the through hole between them, and into each branch channel. A heat exchanger characterized in that a burring portion is formed on the exit side of the through hole of the heat transfer fluid flowing from the enlarged flow path toward the narrow flow path in a fluid circulation state.