Microchannel Heat Exchanger Flow Validation Study

Abstract

Flow maldistribution in microchannel heat exchanger (MCHEs) can negatively impact heat exchanger effectiveness. Several rules of thumb exist about designing for uniform flow, but very little data are published to support these claims. In this work, complementary experiments and computational fluid dynamics (CFD) simulations of MCHEs enable a solid understanding of flow uniformity to a higher level of detail than previously seen. Experiments provide a validation data source to assess CFD predictive capability. The traditional semi-circular header geometry is tested. Experiments are carried out in a clear acrylic MCHE and water flow is measured optically with particle image velocimetry. CFD boundary conditions are matched to those in the experiment and the outputs, specifically velocity and turbulent kinetic energy profiles, are compared.