Experimental and Comparative Heat Transfer Analysis of Heat Exchanger with Surface Modification

Abstract

This research aims to enhance the heat exchanger performance by a surface modification approach. The shot peening effect on the heat transfer performance of shell and tube heat exchanger (STHE) is experimentally studied with different surface modifications of stainless steel (SS) tube-like plain SS tube, grinded surface and blast with copper, sand & iron surface. The effect of shot peening on the surface morphology of the SS outer surface is analyzed by scanning electron microscope, and it was found that the iron blast surface has a coarse grain structure. The optimum flow rate for STHE was experimentally studied by base SS tube, and its values are compared with analytical results of computational fluid dynamics and heat transfer research. The underwater medium maintained the higher and lower temperatures of 80 °C and 30 °C, respectively. Based on the logarithmic mean temperature difference, number of transfer units (NTU), overall heat transfer coefficient, effectiveness and exergy efficiency of SS and its modified surface are experimentally evaluated, and iron blasted surface offered maximum heat exchanger performance like 100% for Stanton number, 89% for Nusselt number, 89% for overall heat transfer coefficient, 89% for an NTU, 57% for effectiveness, and 148% for exergy efficiency, while compared to SS surface without modification.