An optimized natural convection Y-shape-shifted heat sink design problem

Abstract

An optimized design problem for a natural convection three-dimensional Y-shape-shifted heat sink is investigated numerically and experimentally in the present study. The software package CFD-ACE+ and the Levenberg-Marquardt method (LMM) are utilized as the numerical solution solver and design tool, respectively. The objective of this work is to design the optimal fin stem height, fin branch length, branching angle, and shift distance of the Y-shaped fin under fixed Y-shaped fin volume conditions to minimize the base plate temperature and enhance the cooling performance of the heat sink. The thermal radiation effect between the air and Y-shaped fin is considered in this work to improve the accuracy of the numerical solution of temperatures. The result indicates that in the optimized Y-shaped heat sink, the stem height and branching angle become shorter and larger, respectively, than those of the original design. When the shift distance is considered as a design variable, i.e., the optimized Y-shape-shifted heat sink with an up-up-up fin displacement arrangement, the chimney-flow effect due to the buoyant plume is much more pronounced than that of the original design, and a pair of longitudinal vortices also occur; therefore, better heat dissipation performance can be achieved. Experiments were performed on manufactured heat sinks to check the validity of the design results. The results indicated that the measured temperatures of the heat sinks are very close to the computed data since the maximum error between the computed and measured base temperatures is less than 0.81%. In addition, design B1 (a vertical heat sink) has the smallest thermal resistance Rth among all designs at 2.6% smaller than that of the original vertical heat sink, which confirms the validity of the present work in designing the optimal design of the Y-shape-shifted heat sink.