Effect of transverse pitch on forced convective heat transfer over single row cylinder

Abstract

Heat transfer problems are encountered in many engineering fields. Heat exchanger becomes important as the equipment for transfer heat. The tubes in heat exchanger consist of some tubes either in-line or staggered arrangements. The heat transfer of three circular tubes arranged in single row is studied numerically to observe the effect of transverse pitch. The flow around the tube, the momentum equation in boundary layer is solved by finite volume method to obtain the velocity distribution. The energy equation is discretized by finite different methods and then solved by the iteration of relaxation method to obtain the temperature fields. The pressure term of the equation is replaced by the experimental data measured from wind tunnel tests. The calculation of velocity and temperature are carried out around the cylinder in the middle of the arrangement in which the number of nodes increase along longitudinal direction. The results show the local drag friction and the local Nusselt number at the tube surfaces change with transverse pitch. Starting from a certain value of transverse pitch, there is no influence on heat transfers and the tube arrays behave as a single tube. For small pitch, the heat transfer and drag coefficient variations are significant.