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