Modeling Fluid Flow and Heat Transfer in Shell and Tube Heat Exchangers According to Shape and Layout of Tubes

Abstract: Although typical shell and tube heat exchangers (STHE) have a long-standing history and several achievements in the industry, accounting for the majority of new exchangers in refinery, petrochemical and power plants, these equipment have operational problems and limitations. Small shell-side heat transfer coefficient in these exchangers increases the possibility of dead zone creation, and settling in them. In addition, pressure drop is high relative to the heat transfer coefficient and vibration of the tube bundle. In this study, circular and elliptical tubes, and their layout in the exchanger were investigated. Proper placement of tubes in exchangers eliminates simple STHE associated problems. Simple tubes in heat exchangers produce vibration, reduce heat transfer, and increase settling and corrosion relative to the tubes with square or elliptical layout patterns. The majority of these problems are solved through designing tubes with triangular pitch or using elliptical tubes. Laws governing heat transfer reveal the advantage of using elliptical tubes or a certain layout. Fluent outputs were compared to the findings of previous studies and the most optimum layout was proposed.