微細管内における相変化流動特性

抄録

Recently, the development of a small and high efficient heat exchanger, which is utilized in a fuel battery and a heat pump system for Carbon dioxide refrigerant and so on, is strongly required. In the previous study, a prototype of stacked high-pressure resistance microchannel heat exchanger manufactured with diffusing bond technique has been proposed. It has been confirmed that it achieves miniaturization to one hundredth and a heat transfer rate equal to or higher than that of existing heat exchangers. In the present study, the objective is to reveal flow and heat transfer properties of this microchannel heat exchanger when water and vapor are employed as low and high-temperature fluids, respectively. However, what makes these heat exchangers high efficient than previous heat exchangers is not clear. Hence, illuminate that by simulating the microchannels of the heat exchanger. The shape of microchannel is rectangular, and hydraulic diameters is 500 μm. From experimental results, it was shown that the flow performance of boiling and condensation in a microchannel. Furthermore, it is found that the condensation heat transfer is changed by the location of the microchannel.