Bio Inspired Particle Enhanced Capillary Heat Exchanger

This study proposes a new cooling concept using encapsulated phase-change material particles in mini-channels. This novel method is inspired by the gas exchange process in the lung capillaries. An important characteristic of capillary blood flow is that the red blood cells fit very snugly into the capillary opening. Hence, it is conjectured that using particles with diameter similar to the channel diameter, in a manner similar to red blood cells in lung capillaries, is likely to enhance the heat transfer coefficient, even under laminar flow. Preliminary tests are performed with encapsulated Octadecan paraffin (C18H38) in a low-conductivity thin melamine shell, flowing through a test module. The effect of flow rate on the heat transfer coefficient and also the effect of using particles on enhancement of Nusselt number has been measured. Temperature distribution on the chip has also been investigated under various particle concentrations, heat fluxes and Reynolds numbers.