Impact of the Self-Adaptive Valve Behavior on an Array of Microfluidic Cells under Unsteady and Non-Uniform Heat Load Distributions

Previous studies have demonstrated that the performance of a cooling scheme based on a matrix of microfluidic cells with self-adaptive valves under unsteady and non-uniform heat load scenarios improves in terms of pumping power and temperature uniformity, compared to the ones from conventional microchannels and hybrid jet impingement/microchannel cooling devices. The behavior of the thermally dependent self-adaptive valves varies as a function of some design parameters. In this work, the impact of the valve’s characteristic curve on the cooling device is assessed to establish the basic rules for the valve design. The performance of a 3×3 microfluidic cell array is numerically studied under an unsteady and non-uniform heat load scenario. The results show that the valves which open at the most elevated temperature (control temperature of 90ºC) reduce by 15.5% the pumping power with respect to the valves opening at 60ºC, while improving by 25.0% the temperature uniformity and reducing both the overcooling and the fatigue.