Title: An Experimental Study and Numerical Modeling of the Flow in a Network of Triangular Microchannels
Abstract: The flow characteristics of a network of parallel microchannels (hydraulic diameter: 110 μm) are investigated both experimentally and numerically. The microchannel cross-section was triangular, as in the case of microheat pipes. The pressure drop across the microchannel network showed a dramatic increase with a departure from the law of fully developed flow in ducts as soon as the Reynolds number of the flow exceeded about 10. Numerical computation of the flow was carried out using the classical laws of hydrodynamics in an attempt to explain this surprising result. There was a good agreement with experimental results, which suggests that there are no size effects at the length scales used in the experiments. Moreover, the mechanisms responsible for the large pressure drop for higher Reynolds numbers were identified in the numerical analysis as being extra head losses due to separation in several parts of the test section. Acknowledgments This research was supported by the Rhône-Alpes Region. The authors would like to gratefully acknowledge the Socrates program for partly supporting the visit of Mariusz Niklas to Grenoble. They also wish to thank Nicolas Mazellier for performing the experiments.