Numerical investigation of shell side performance of a double shell side rod baffle heat exchanger

A double shell side rod baffle heat exchanger (DS-RBHX) is proposed, and comparisons between single shell side rod baffle heat exchanger (SS-RBHX) and DS-RBHX in terms of the heat transfer and pressure drop in the shell side are presented in this study. A realizable k-epsilon model is adopted to solve the turbulent flow problem. All numerical simulations are carried out under mass flow rate M ranging from 3 kg/s to 10 kg/s for the SS-RBHX and DS-RBHX. The results demonstrate that under same mass flow rate M, the heat transfer rate Q and pressure drop Δp of the DS-RBHX are higher than those of the SS-RBHX by 34.5-42.7% and 41.6-40.6%, respectively. Moreover, under same mass flow rate M, the comprehensive performance index h/Δp of the DS-RBHX is higher than that of the SS-RBHX by a maximum of 8.9%. An efficiency evaluation criterion EEC, the ratio of the gain in heat transfer rate and cost in power consumption, is adopted to evaluate the comprehensive performance in the present study. The EEC of the DS-RBHX is approximately equal to and larger than 1, which indicates that the cost in power consumption of the DS-RBHX is offset by the gain in heat transfer rate. The DS-RBHX is demonstrated to be effective in enhancing heat transfer and improving the comprehensive performance of rod baffle heat exchangers.