| 摘要 |
PURPOSE:To permit to uniform the layer of frost between fins, elongate a time until a space between fins is blockaded by frost and reduce the number of defrosting operation by a method wherein respective fins of the groups of fins, arranged in parallel with a given space and air flows therebetween, are corrugated and the pitch of corrugation is set so as to be shortened stepwisely toward the outflow direction of the airflow. CONSTITUTION:The pitch Pf1 of corrugation of the corrugated fin 4 at the inflow part of airflow is long, therefore, disturbance of airflow is not generated easily and the difference between absolute temperature of ambient air, related to the amount of frosting, and saturated humid air corresponding to the temperature of heat exchanging heat transfer surface becomes small. As a result, the thickness of layer 3 of frost at the air inflow part becomes thin. The gradually cooled and dehumidified air generates the disturbance gradually since the pitch Pf is shortened step-wisely toward the outflow direction of air, accordingly, the layer 3 of frost is formed as the result of heat exchange between the cooled and dehumidified air. According to this method, the thickness of layer 3 of frost on the surface of the corrugated fin 4 becomes uniform, a space between fins will never be blockaded even the fins are frosted, the width of ventilating path may be secured widely and the number of defrosting operation may be reduced. |
