A microchannel experimental apparatus for heat exchanging: design and analysis

An experimental apparatus is developed for testing the heat-exchange performance of microchannel structures. This system mainly consists of microchannel heat exchangers, a simulated heat source, a micro-pump; a few of pipes, some three-way pipes and other test devices. The heat exchange coefficients and the fluid resistant in microchannels can be obtained by testing temperature, pressure and flow rate. The fluid resistance and heat transfer performance of microchannels are analyzed and investigated based on this experimental apparatus. It is shown that classical macroscopic formulas are not applicable for calculating friction resistance and heat exchange coefficients when channel hydraulic diameter is 381 μm. In this case, the flow resistance is smaller from 31.6% to 41.9% than that of calculated by classical macroscopic formulas, and the microchannel structure has a satisfied heat transfer performance while Nussle number being 9.2.