Modeling and simulation on the mass flow distribution in microchannel heat sinks with non-uniform heat flux conditions

This paper describes modeling and numerical simulation on the mass flow distribution in microchannel heat sink, which is a promising device for cooling miniature electronic systems. The microchannel heat sinks in this study consist of headers, multiple fluidic channels and port holes, all of which influence flow distribution in the multiple channels. This study focuses on design of the header with non-uniform heating conditions over the channel area. To investigate the effect of non-uniform heat flux, three different non-uniform heat flux conditions were applied. The simulation work has been carried out to find optimal header geometry for two-phase flow in the microchannel heat sinks. The header geometry was expressed in mathematical terms by defining a geometric parameter of header shape, n. For the optimal design of microchannel heat sinks, absolute average deviation and root mean squared deviation of the flow distribution under various header shapes have been calculated as well as pressure drop. The results show that mass flow rate distribution tends to be less changed among microchannels over a certain value of n.