Numerical study of heat transfer and pressure drop for flow past inline and staggered tube bundles

Purpose - The purpose of this paper is to develop an indigenous three-dimensional computational code and apply it to compare flow and heat transfer characteristics for inline and staggered arrangement of circular tubes in a tube bundle. Design/methodology/approach - A finite-volume based computational code is developed to solve the momentum and energy equations for flow through a three-dimensional rectangular channel and past built-in tube bundles having inline and staggered arrangement. The approach is based on SIMPLE algorithm. The basic conservation equations of mass, momentum and energy are solved over a body-fitting grid on the physical domain to obtain the flow and temperature fields. Findings - Heat transfer and pressure drop are compared for inline and staggered tube arrangements in a tube bundle over range of Reynolds numbers 300 <= Re <= 800. Results are validated suitably against those available in literature. Research implications - Tube-fin heat exchangers with continuous fins on a tube array are commonly used in air-conditioning industry and in air-cooled condensers of power plants. The flow structure within the finned tube bank is complex due to the presence of a circular tube, which causes flow acceleration over the fin surface and flow separation on the back side of the tube resulting in low velocity wake region. The present study provides a better understanding of flow behavior and heat transfer for inline and staggered arrangement of tube bundles in tube-fin heat exchangers at different Reynolds numbers. Originality/value - A numerical code based on finite volume method has been developed and used for computations to predict heat transfer and pressure drop characteristics for flow past inline and staggered arrangement of circular tubes. Predictions are made from the computed results about suitability of staggered/inline tube arrangements in a given range of Reynolds number.