Experimental Study on Longitudinal Flow Heat Exchanger with Mixed Tube Bundle

摘要

Mixed tube bundle heat exchanger is a new type of thermal equipment with the merits of both plate heat exchanger and shell-and-tube heat exchanger. Mixed tube bundle is composed of various kinds of tubes with different configurations and dimensions or enhanced tubes and plain tubes. It is applicable to different flow patterns and fluids by adjusting the numbers of plain tubes, enhanced tubes and the structures of both. For different operation conditions, structure optimization is convenient and applicable to enhance overall heat transfer with mixed tube bundle while maintaining low pressure drop. Experimental study on the longitudinal flow shell-and-tube heat exchanger with mixed tube bundle is performed. The results indicate that heat transfer coefficient of mixed tube bundle is about 1.3～2.3 times that of the plain tube bundle. With mixed tube bundle, high heat transfer coefficient can be acquired with not too high pressure drop. The heat exchanger with mixed tube bundle may prevent flow-induced vibration caused by transversal flow for the pin fins support each other for fluid longitudinal flow pattern. At the same time, it may reduce the weigh of equipment investment and operation cost.