JPS5819692A - Fin for heat exchanger - Google Patents

Abstract

PURPOSE:To remove the water drop adhering to the leading end of a louver and consequently impove the heat transfer performance at lower air velocity by a method wherein a large number of the louvers erecte by lancing over the surface of a fin are slantingly provided in such a manner that the positions on the louver along air flow are gradually lower toward the direction of gravity. CONSTITUTION:In the heat exchanger, which has fins (not shown) contacting with air and in which fluid with the temperature lower than air temperature flows, a large number of the louvers 6 erected by lancing over the surface of the fin are slantingly provided in such a manner that the positions on the louver 6 along the air flow 7 are gradually lower toward the direction of gravity as indicated with the arrow head 14. Accordingly, the water drop 8 adhered to the louver 6 is adhered to the trailing end of the louver 6 by being pulled by air flow as indicated with the white arrow heads 7 and by gravity as indicated with the arrow heat 14. Because the leading end of the louver 6, which is the portion with high heat transfer performance, is not covered with water drop and the air flow 9 passing between the louvers flows without obstruction, the heat transfer performance of the heat exchanger can be kept high even at lower air velocity.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fin for a heat exchanger, and particularly to a looper corrugated fin suitable for an evaporator of a room air conditioner in a carnivorous unit.

The looper corrugate fins used in conventional corrugate fin type heat exchangers are rounded to improve drainage of the looper at the air outlet end, and the fins are sloped along the air flow.
It was tilted so that it gradually became lower in the direction of gravity,
In this way, the looper gradually moves to a higher position along the air flow, and at low wind speed W#, water droplets adhere to the tip of the looper.1. This had the disadvantage of reducing heat transfer performance.

An object of the present invention is to provide a fin for a heat exchanger that removes water droplets that adhere to the tip of the looper at low wind speeds and has high heat transfer performance.

By arranging a large number of loopers on the fin surface so that they become gradually lower in the direction of gravity along the direction of airflow, the present invention can reduce the force of the airflow pulling water and the direction of gravity of water. The present invention is characterized by reducing the amount of water droplets adhering to the tip of the looper and improving heat transfer performance at low wind speeds.

Hereinafter, as an embodiment of the heat exchanger fin of the present invention, a case where the fin is applied to a car air evaporator will be explained with reference to FIGS. 1 to 4. The nine flat tubes IK are bent into a meandering shape, and an inlet header 2 and an outlet header 3 are attached to the refrigerant inlet and outlet sides thereof. Moreover, corrugated fins 4 are closely attached between the straight portions of the flat tube 1. This rug gate fin 4 is bent as shown in FIG.
A large number of loopers 6 are cut and raised. FIG. 3 shows a cross section taken along ■-■ in FIG. 2, and the corrugated fin 4 is
The position is gradually higher in the direction of gravity along the direction of air flow. But Loopa 6.

It is tilted to a gradually lower position along the air flow 7. Therefore, the water droplets 8 adhering to the louper 6 are pulled by the air flow 7 and gravity and adhere to the rear end of the louver as shown in Figure #I4. The portion with high heat transfer performance at the tip of the looper is not covered with water droplets, and the air flow 9 at the looper section flows unhindered, so high heat transfer performance can be maintained even at low wind speeds.

Figures 5 and 6 show examples of nine effects obtained by Jin's invention.
This will be explained with a diagram. FIG. 5 compares the difference between the conventional louver and the louper of the present invention, with the horizontal axis representing the wind speed and the constant temperature difference, and the vertical axis representing the amount of heat exchanged over a constant area. In a high wind speed region (wind speed of 25 m/$ or more), there is almost no difference between the two, but in a low wind speed region (wind speed of zstn/s or less), the heat transfer performance of the looper in the present invention is excellent.

The usage range of car air conditioner wind speed is s 1.5 m/
m is also 2.5ff)/IT, so it can be seen that the looper of the present invention is excellent within the range of use. 6th
The figure is a comparison of the ventilation resistance of the same conventional looper and the looper of the present invention. No difference was observed in ventilation resistance.

FIG. 7 shows another embodiment of the heat exchanger fin of the present invention, in which the fin 4 is a corrugated twin looper parallel to the incoming air 7. In such a case, all loopers cannot be oriented in the same direction. This is to prevent air from flowing to one side. In FIG. 7, two-thirds of the entire looper is gradually tilted to a lower position along the air flow.

If the looper fins are provided in such a manner that as many loopers as possible are gradually inclined to lower positions along the air flow, an evaporator with high heat transfer performance can be obtained.

As described above, according to the present invention, the multiple loopers on the fin surface are tilted at 9 so that the position in the gravity direction gradually decreases along the air flow direction, so that the heat transfer performance at low wind speeds is improved. High heat exchanger fins can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a corrugated fin type heat exchanger which is an embodiment of the heat exchanger fin of the present invention, FIG. 2 is a perspective view of the 11-pack corrugated fin in FIG. 1, and FIG.
1t-it sectional view in the figure, FIG. 4 is a diagram showing the state of water droplet adhesion on the fin in the embodiment shown in FIGS. 1 to 3, and FIGS. 5 and 6 are replacements of the conventional looper and the looper of the present invention. FIG. 7 is a diagram showing a comparison of heat quantity and ventilation resistance, and is a diagram showing another example of the fin for a heat exchanger of the present invention. 1... Flat tube, 2... Inlet header, 3... Outlet header, 4... Corrugated fin, 6... Looper, 7
... Air flow, 8... Adhering water droplets, 9... Air flow around the looper, lO... Heat transfer performance of conventional fins, 11...
- Heat transfer performance of the fin of the present invention, 12... Ventilation resistance of the conventional fin, 13... Ventilation resistance of the fin of the present invention. Agent Patent Attorney Toshiyuki Usuda 1st Figure ¥14 Figure 14 '1f15 Figure t )70~4ノ'yfJ6 Figure 1, 1 Gin (Ontano

Claims (1)

[Claims] In a heat exchanger consisting of fins in contact with the air and passages through which a fluid with a lower temperature than the air flows, a large number of loopers cut out on the fin surface are arranged so that the position in the direction of gravity gradually becomes lower along the air flow. A fin for a heat exchanger, characterized in that the fin is provided at an angle.