Numerical evaluation of doubly clamped self-adaptive fins acting as vortex generators inside micro heat sinks (MHS)

Abstract

The continuous increase in the power density of integrated circuits (ICs) has placed thermal management as a key focus for the ICT community. Current liquid cooling systems are usually not optimized for the real operating conditions of advanced electronics, which have heat loads that can vary in time and space. Hence, conventional cooling devices lead to non-uniform temperature patterns at the package level and overcooled systems. This work proposes the use of thermally adaptive actuators, based on doubly clamped fins able to change its shape with temperature, to improve the performance of micro heat sinks with an optimized adaptation to temporal and spatially variable thermal parameters. The effect of this thermally responsive bistable fins on the efficiency of two different micro heat sinks (MHS), one based on microchannels and other on a matrix of microfluidic cells, is numerically evaluated. Results demonstrated a maximum heat transfer enhancement of 40% when adding the clamped-clamped fins within a microchannel and 20% when the fins were placed inside a microfluidic cell. Additionally, savings on hydraulic pumping power have been quantified between 8% and 11%.