No abstract

Improvement of heat transfer using surface protrusion (convex strip) has been effective recently. Surface protrusion is able to improve flow mixing which increases the rate of heat transfer. Therefore, this study aims to improve the heat transfer in a fin-and-tube heat exchanger by fitting convex strips around the tubes. Three-dimensional modeling was carried out by placing four and eight convex strips around the staggered tubes at a constant temperature of 106 • C. The turbulent k-ε model was applied at a Reynolds number range of 3438-15,926.The results of the study indicate that tubes with eight convex strips demonstrated a heat transfer improvement of 40.46%, compared to that with four convex strips. In this case, the TEF is 6.27% higher than the four convex strips. In addition, the synergy angle in the eight convex strips configuration was 0.13% lower than that of the four convex strips configuration. Meanwhile, the flow resistance in the tubes with eight convex strips configurations was 30.96% higher than that of the four convex strips.