Frederik Rogiers

On the use of second law based cost functions in plate fin heat sink design

This paper discusses the use of the second law in heat sink design. A new entropy-based cost function is proposed and compared with existing heat sink cost functions. A case study of a plate fin heat sink points out that this newly developed cost function offers a heat sink which is more than twice as efficient as a heat sink designed with the traditional thermal resistance minimization objective. The effects of this new heat sink design on data center cooling systems are considered and found to be significantly improving the system efficiency and waste heat recovery.

Collector Pressure Losses in Micro Heat Exchangers

As collector losses are expected to play a crucial role in micro heat exchangers, an experimental method is developed to determine these losses. Experiments are performed on a micro heat exchanger consisting of 42 parallel microchannels positioned in a 6 by 7 matrix, with hydraulic diameters in the range of 260-280 mum. The proposed method is successfully applied. From the experimental results it can be concluded that the pressure drop of a small collector performs according to classical correlations. However, in a wider collector design the pressure drop clearly deviates from macro scale behaviour

Digital and Continuous Liquid Cooling for Electronic Systems

In this paper both digital and liquid cooling concepts are proposed. Microchannel cooling techniques either actuated by a separate feed pump or actuated by electrowetting are investigated and their cooling capabilities and pumping requirements are assessed. Though the continuous liquid microchannel cooling clearly outperforms the other systems with respect to global thermal resistances, the low energy consumption and the flexibility as a reconfigurable cooling system, make the electro-actuated cooling systems attractive.