Experiments on Reduction in Drag of Circular Cylinder at Transonic Speed by Using Wire
Abstract
The effects of small diameter of wires on reducing drag of flow around a circular cylinder at transonic speeds were examined experimentally. The wires were attached longitudinally at an asymmetrical location with regard to the symmetry plane and acted as a barrier restricted upstream propagation of instabilities originate in the downstream wake. The experiment was investigated at Mach numbers of 0.6 and 0.73 and the flow was considered laminar boundary layer on the cylinder surface. The results clearly showed that depending on the Mach number, the wires effectively reduced the pressure drag by 13.2% for Mach number 0.6 and 4.4% for Mach number 0.73, respectively. Assuming the existence of shock waves that produced so-called wave drag, the wires also reduced the total drag: by 14% for Mach number 0.6 and 6% for Mach number 0.73References
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