ABSTRACT
The fluid flow past an obstacle of circular cross-section represents a classical fluid mechanics problem and has received much attention for over a century or so. In the present study, the heat transfer from a two-dimensional circular cylinder is considered in the unsteady flow regime. In particular, the effect of Reynolds number on the heat transfer characteristic of a long circular (heated) cylinder is investigated for the range of conditions: Reynolds number = 100 and 150 and Prandtl number = 0.7 (air) in the unconfined unsteady cross-flow. The numerical simulations have been carried out by using finite volume method (FVM) based commercial CFD solver Fluent (version 6.3). The present results are found to be in an excellent agreement with the experimental/numerical data available for a circular cylinder in the literature. Heat transfer results are presented here by the variation of Nusselt number with time as well as by isotherm profiles for the above range of conditions. The average Nusselt number increases with increasing Reynolds number.
Keywords: Circular cylinder, Unsteady regime, Reynolds number, Nusselt number.
