Department of Mechanical and Mechatronics Engineering, Southern Illinois University Edwardsville Edwardsville, IL 62026, USA
Heat transfer from cylinders has wide engineering applications. Despite the abundance of experimental and computational results for long cylinders in crossflow, heat transfer from short cylinders parallel to the flow is scarce. This paper considers turbulent heat transfer from a short cylinder placed in a uniform flow. It investigates the effect of cylinder length, Reynolds number, and Prandtl number on the convective heat transfer coefficient. The length-to-diameter ratio, Reynolds number, and Prandtl number range are 0.25-2, 5000-42,000,
and 0.707-100, respectively. Detailed grid refinement studies confirm that the results are independent of the grid. Comparison with experimental and theoretical results and correlations validate the current results. This paper presents the average Nusselt number for cylinder faces and the cylinder as a whole. The main outcome is a correlation for the cylinder Nusselt number. Furthermore, images of the flow and thermal field reveal the complexity of the flow field. The front stagnation point flow, the lateral flow separation, and the rear wake region show a diverse and complex flow field affecting turbulent heat transfer from the cylinder.