Convective heat transfer enhancement in a circular tube with microfiber fin

In order to develop a novel heat transfer enhancement technique with high heat transfer rates and less additional pressure loss, the thermal performance of a single fiber fin in internal laminar flow was theoretically analyzed. With inlet temperature and velocity being assumed fully developed the analysis reached the fact that the heat transfer coefficient along the fin surface was far greater than that of the tube wall. Analytical results show that the fiber fins can effectively enhance heat transfer. The effect of a single fiber fin on the heat transfer enhancement is mainly dominated by two parameters: the length-to-diameter ratio (D/d) and the thermal conductivities ratio of the fin, and the fluid (λs/λf). The heat transfer improves monotonously as D/d increases. The heat transfer enhancement depends strongly on λs/λf) when it is relatively small, and the thermal conductivity ratio becomes little effect when λs/λf is relatively large.