HE HEAT TRANSFER AND FLOW FRICTION CHARACTERISTICS OF A WAVY FIN, A STRIP FIN, AND A PERFORATED FIN HEAT TRANSFER SURFACE

摘要

Basic heats transform and flow friction characteristics of throe compact high-performance boat exchanger surfaces arc presented. Two of the configurations, a strip-fin surface and a wavy fin surface, are quite similar to pre-visually tested geometries. The third is a perforated fin con-figuration in which the fins have been punched with 0.079 inch holes spaced 32 holes per square inch. The behavior of the strip and wavy fin surfaces is approximately as would be pre¬dicted on the basis of previously tested geometries. The perforated fin configuration is unusual, however. in that evi¬dently a substantial increase in convection conductance has been obtained without paying a large price in terms of form dreg on the fins.