Effect of winding angles on flow and heat transfer characteristics in the shell side of spiral wound heat exchangers

Abstract

A three-dimensional model is established to investigate the flow and heat transfer characteristics influenced by the winding angle in the shell side of a spiral wound heat exchanger. Numerical simulations are conducted with the winding angle varying from 0° to 20° and the Reynolds number varying from 430 to 1935. The flow states of different conditions are observed, and the film thickness is measured in the axial and circumferential directions. Moreover, the heat transfer characteristics of the liquid falling film flow are investigated at constant wall temperature. The results indicate that the winding angle has a distinct effect on the flow and heat transfer characteristics. Under the same Reynolds number, the local film thickness distribution varies with the winding angle, and the average film thickness in the axial direction decreases with the increase of winding angle. The local heat transfer coefficient distribution is consistent with that of film thickness, and the average heat transfer coefficient increases with the Reynolds number but decreases with the winding angle. Based on the results, a comprehensive heat transfer correlation involving winding angles is developed, the deviations of the data are within ± 3%.