Fluid Flow and Heat Transfer around Two Circular Cylinders of Different Diameters in Cross Flow

Abstract

The heat transfer mechanism in separated region of a cylinder immersed in a free stream with non-homogeneous and unisotropic turbulence was made clear experimentally in relation to the wake formation process near the cylinder and the flow behavior in the layer close to the cylinder wall. An experiment was conducted in the subcritical flow region. The appearance of a second peak of heat transfer coefficients in separated region is due to the existence of a three-dimensional unsteady flow close to the cylinder surface and the decrease of heat transfer coefficients in near stagnation region is caused by the formation of an apparent turbulent separation point.