Effect of Surface Temperature on Rarefied Flow Past a Circular Micro-Cylinder

A high-order moment method is employed to study the effect of the wall temperature on gas flow past a stationary circular cylinder in terms of the size of the vortices behind the cylinder and the drag coefficient. When the wall temperature is lower than the free stream temperature, flow separation occurs at a lower Reynolds number and the vortex length is elongated with a corresponding reduction in the drag coefficient. Conversely, increasing the wall temperature above the free stream temperature delays the onset of flow separation and increases the drag coefficient.