Design Optimization of a Shell-and-Tube Heat Exchanger Based on Variable Baffle Cuts and Sizing

Abstract

This article investigates the optimization of a shell-and-tube heat exchanger design through the optimization of baffle spacing and cut. This study focuses on the impact of baffle spacing (20–35%) and baffle cut percentage (20–35%) on heat transfer performance while considering the effect of the presence or the absence of seals. This study aims to optimize the heat exchanger design by using computational fluid dynamics (CFD) to reduce the pressure drop and increase the heat transfer. Studying the flow in heat exchangers is challenging due to its complex physics, especially in nonstandard geometries or novel fluid systems, which makes traditional methods relatively less accurate compared to modern approaches. The following fluid is so far uninvestigated for CFD analysis of heat exchangers: a mixture of 80% ethanol and 20% water is used as the tube-side fluid and water is used as the shell-side fluid. The Bell–Delaware method is employed for initial thermal analysis, followed by CFD simulations using ansys fluent to assess the influence of design modifications on heat transfer efficiency and pressure drop. The presence of seals is shown to improve the heat transfer efficiency by about 10.9% compared to the case when seals are absent, while optimal baffle spacing and baffle cuts are able to increase the efficiency of the heat exchanger by about 110% not inclusive of the effect of seals. Our findings show that the performance of a shell-and-tube heat exchanger is improved dramatically by the addition of seals and optimal selection of baffle cut and spacing.