Numerical studies on the effect of baffle on the heat transfer and flow in cross-corrugated triangular ducts

Abstract

The cross-corrugated triangular ducts are suitable for plate heat exchanger because of its high heat transfer capability and strong mechanical strength. In this numerical study, a SST k-ω model is used, 6 different cases for installing different baffles in the cross-corrugated triangular ducts are involved. The frict ional resistance and heat transfer coefficient in the 1000-6000 range of Reynolds number are studied, the influence of baffle on flow-pattern and temperature distribution are analyzed. Combined with the comprehensive heat trans fer index, a good improvement plan was proposed. The results show that baffle can effectively increase the heat transfer area, change the mainstream direction, enhance the fluid disturbance, and enhance the heat transfer. In addition, case 6 is the best enhanced heat transfer scheme. Compared with the case without the baffle, the Nu of case 6 is 1.5-1.6 t imes that of the original duct, and the heat transfer efficiency can be increased by 13% under the same fan power. It is a feasible choice to set up baffles in the middle and lower part of the upstream channel of the cross-corrugated triangular plate flow channel.