Effect of cross-flow on heat and mass transfer rates at the outer surface of a spiral tube placed in a cylindrical container and possible application in heat exchanger/reactor design

Abstract

This research investigates the effect of cross-flow on heat and mass transfer rates at the outer surface of a spiral tube placed in a cylindrical container and its potential application in heat exchanger/reactor design. The study evaluates various parameters such as solution velocity, spiral tube diameter, and pitch through electrochemical methods under laminar flow conditions. Results indicate that the mass transfer coefficient increases with rising solution velocity but decreases with larger spiral tube diameters and pitches. A dimensionless equation is proposed to correlate the mass transfer data for a single spiral tube, which proves valuable for designing and scaling up heat exchanger/reactor systems. The research also highlights the dual functionality of the spiral tube, with the outer surface serving as a catalyst support for an exothermic, diffusion-controlled liquid-solid reaction, while the inner surface acts as a cooler, efficiently absorbing heat generated on the outer surface. The study explores the application of this novel reactor design for heat-sensitive materials and processes requiring swift cooling, such as immobilized cell or enzyme biochemical reactions. The findings contribute to enhancing reactor productivity and achieving high selectivity and yield in electro-organic synthesis.