Numerical investigation of the flow dynamics and heat transfer in a rectangular shell-and-tube heat exchanger

Numerical simulations have been carried out to investigate the turbulent flows and coupled conductive/convective heat transfers in a glycol to water shell-and-tube heat exchanger (one shell, one tube doing six passes). The refrigerant (glycol) flows in the tube, and a secondary fluid (water) flows in the shell. The k-omega SST model is used to close the system of equations in the turbulent regime. The present model is first favorably compared and validated against experimental and numerical researches for a concentric annular heated pipe for two radius ratios (R * = 0.1 and 0.5) at a bulk Reynolds number Re-Dh, = 8900 and a Brandtl number Pr = 0.71. It is then extended to consider the shell-and-tube configuration with a rectangular shell. Its thermohydraulic performances in the tube side are quantified for different Reynolds numbers at the cold inlet ranging from 1.03 x 10(3) to 1.47 x 10(5). The performance of the heat exchanger is then enhanced by introducing baffles in the rectangular shell. The results are finally discussed in terms of three global performance metrics.