Numerical Study of Shell and Tube Heat Exchanger Performance Enhancement Using Nanofluids and Baffling Technique

Abstract

The aim of this work is to investigate the forced convective heat transfer phenomena and fluid flows of water-based Al2O3 nanofluids in the baffled shell and tubes heat exchanger (STHE). Water as a hot fluid flows in the side of the tubes, and Al2O3 nanofluids as cooling fluid flow in the shell side. Numerical investigations have been carried out based on the continuity, momentum, and energy equations which are solved by using the finite element method with the help of the COMSOL 5.4 CFD software. The obtained results were presented by average Nusselt number, streamlines, isotherms, and various physical parameters which are a volumetric fraction of nanoparticles (1%≤ Cv ≤3%). The obtained results reveal an increase in the heat transfer with the rise of inlet velocity and volume fraction, where the Nusselt numbers are augmented by 0.1 %, 3.96 % and 7.62 % for Cv = 1%, 2% and 3%, and the friction factor are increased by 22.41 %, 24.14 % and 26.72 % for Cv = 1%, 2% and 3% compared with base fluid respectively. In addition, the presence of baffles inside tubular heat exchangers can create a better mixture of fluids which is augmenting heat transfer execution. The choice of these parameters is important to get the maximum improvement of heat transfer with minimum entropy consumption.