Flow control behind a circular cylinder by control rods in steady flow

초록

Flow control that attached different sized control rods to the rearward stagnation point of a circular cylinder was carried out in a circulating water channel by PIV technique. Reynolds numbers varied from Re = 5,000, 10,000, 15,000, 20,000 to 25,000 based on the main circular cylinder diameter(D=50mm). Wake velocity distributions were measured with varied control rods and Reynolds numbers. The measured results were compared with each other. The results indicated that the flow control by rods has different effects according to the change of inflow. Strong time mean turbulence intensity appeared within X/D=3.5. The control rod, d/D=0.3 has an outstanding effect to reduce the turbulence intensity around the circular cylinder. Copyright ? 2008 by The International Society of Offshore and Polar Engineers.