Development of a new air-cooling heatsink for a high density computer system

A novel forced-convection air-cooling heatsink constructed to meet increasing demands for high-speed and high-density computer equipment is discussed. The fin surface of the heatsink has many perforations and is bent to form a trapezoidal shape. The heatsink constructed with these fins has alternating expansion and contraction parts along the flow passage. The heat-transfer enhancement is studied experimentally by changing the fin-surface geometries, and the application to real equipment is investigated by a board-level model. It is shown that the heat-transfer coefficient of trapezoidal fins with many perforations is about two times that of the parallel plate fins for the same frontal velocity, and that this type of heatsink is applicable to computer cooling