Analysis and experimental verification of weight saving with trapezoidal base heat sink

Abstract

A quick weight saving methodology with trapezoidal base heat sink applicable for electronic cooling application is studied analytically, numerically, and experimentally. The conventional heat sink with rectangular base can be modified into trapezoidal base for material saving. A differential equation capable of describing the temperature distribution of the trapezoidal base is derived and its closed-form analytic expression is derived. It is found that three parameters rA (ratio of effective surface area to the base area), rd (ratio of chip lateral length to the base length) and h+ (modified convection heat transfer coefficient) play pivotal roles in balancing the material saving and the performance loss. When rd = 0.1, the material saving for rt = 0.6 is about 18%; while the corresponding performance loss is 2.93%. When rd = 0.2, the material saving for rt = 0.6 is about 16%; while the corresponding performance loss is 2.47%. The analytical results are verified with experiments with good agreement.