Study on Thermal Hydraulic Characteristics of the Stacked High Pressure Resistance Microchannel Heat Exchanger Available to Purchase

Recently, development of a small size and high efficient heat exchanger, which is utilized in a fuel battery and a heat pump system for CO₂ refrigerant and so on, is strongly required. In author’s previous studies, the prototype of the stacked high pressure resistance microchannel heat exchanger manufactured with diffusing bond technique has been proposed. The objectives of the present study are to reveal flow and heat-transfer properties of counter-flow microchannel heat exchanger and to reveal the heat transfer mechanism with condensation in a microchannel. As the results, it is found that heat transfer rate of the present heat exchanger with high- and low-temperature water as working fluids is approximately 8 kW which is 2 kW higher than that of the existing heat exchangers. It is suggested that the flow pattern in a microchannel transits from annular flow to injection flow, and finally it becomes bubbly flow.