| 摘要 |
PURPOSE:To largely increase the heat transfer coefficient of the title heat exchanger, by increasing a turbulence promoting effect and the effect of front edge of a boundary layer by providing 1 raisings opened to an air flow on a plate fin up and down alternately, and by gradually increasing the number of raisings toward the ends of a plate fin. CONSTITUTION:The efficiency of fins is increased by providing raisings 14a-14b, increasing the number of them one to two from the center part to the ends of a plate fin, leaving the base board of a plate fin 11 in the vertical direction to an air flow B. The feet 15a-15c of raisings 14a-14c are disposed at an angle to the direction of the normal line of front edge of a plate fin 11, so that swirls are produced at the feet 15a-15c and the effect of turbulence can be promoted. At the same time dead water areas 16a, 16b are decreased, while effectual heating areas are increased. Because the height 'h' of a raising is nearly 1/2 of the pitch 'Pf' of a plate fin 11, the raisings 14a-14c are uniformly arranged between neighboring plate fins 11, so that the speed of an air flow B becomes uniform and the rate of air passing through the raisings 14a-14c increases. In such a manner the effect of front edge of a boundary layer and the turbulence promoting effect can be largely increased.
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