EXPERIMENTAL INVESTIGATION OF THE INFLUENCE OF THE CROSS FLOW IN THE NOZZLE REGION ON THE SHELL-SIDE HEAT TRANSFER IN DOUBLE-PIPE HEAT EXCHANGERS

摘要

In shell-and-tube heat exchangers, the shell-side fluid flow enters and leaves through nozzles which are mounted on the shell wall. The cross-flow in the nozzle region has an impact on the shell-side pressure drop and heat transfer. The influence on the heat transfer is investigated by means of experiments with four double-pipe heat exchangers. The results show that the influence is greater, the shorter the heat exchangers are, and the smaller the ratio of the free cross sectional areas of the nozzle to that of the shell-side. A correlation suitable for predicting the heat transfer coefficient is presented in this paper. The correlation consists of the Nusselt number for the flow in the nozzle region and that for the flow in the annulus.