Numerical Study of a Shell and Tubes Heat Exchanger: Impact of the Geometrical Change of the Tube Section on the Overall Exchange Coefficient and the Pressure Drop

Abstract

Shell and tube heat exchanger is the most widely used type in industry because of its advantages:solid design, excellent reliability, compact, resistant to fouling fluids, having a very high exchangecoefficient...etc. Several studies have highlighted the importance of this configuration. This study consists in thedesign and the thermo-fluid simulation by COMSOL software of a shell and tube exchanger with two differenttubular geometries: i) circular, ii) square, iii) elliptical 90° using segmental baffles at 25% and two workingfluids: water-air. The mass flow rates of the two fluids are varied and their influence on the energy performanceof the heat exchanger is also examined. The results show that changing the geometry of the tube bundles affectsthe pressure drop especially on the shell side, the square geometry created a higher pressure drop than thecircular tube geometry. A considerable improvement in the overall exchange coefficient was recorded for theexchanger with the circular tube bundle by increasing the fluid velocity.