Heat transfer calculations of high-Reynolds-number flows around a circular cylinder

摘要

Heat transfer calculations of the flow around a circular cylinder are conducted in a range of Reynolds numbers significantly higher than those for any previous attempts on such problem. This is a challenging numerical simulation problem because the heat transfer rate, critically dependent on the molecular process in the thin boundary layer, can not be determined without the velocity and temperature gradients being precisely computed on the surface of the cylinder. The numerical instabilities encountered in the turbulent wake further complicate the problem. In the present simulation, this difficulty is resolved by including a small subgrid scale viscosity which, at the wall, is only a small fraction of the molecular viscosity. The subgrid viscosity does not affect the heat transfer rate but is effective in suppressing the numerical instabilities initiated by turbulence of the subgrid scales in the wake.