Numerical analysis on the flow and heat transfer in a rectangular passage with sub-scale fins

Numeration analysis was made to simulate the flow and heat transfer in a rectangular passage with different configuration of sub-scale fins, the velocity fields, temperature fields and the average Nu were obtained, the enhancements of heat transfer were compared. The calculated results show that; the lower the sub-scale fin fixed on the main fin, the more heat emanated from the hot surface transfers to the fluid; in the region far from the hot surface, the higher specific surface area of the sub-scale fins, the better enhancement of heat transfer, with the same patulous area, the bigger fin length-to-width ratio, the better effect of heat transfer; numerical simulation result and analysis reveals the universal principle that the generalized temperature gradient uniformity principle, which can controls the best configuration of sub-scale fin. The better configuration of sub-scale fin which can enhance heat transfer has been conformed. Analyze shows that generalized temperature gradient uniformity principle can control the enhancement of heat transfer in the convective heat transfer process.