Flow Visualization Around a Non - Circular Tube

The flow behavior around a cam shaped tube in cross flow has been investigated experimentally using flow visualization and pressure distribution measurement. The range of attack angle and Reynolds number based on an equivalent circular diameter are within 0 ≤ α ≤ 360˚ and 2 x 104 < Reeq < 3.4 x 104, respectively. The pressure drag features are clarified in relation to the flow behavior around the tube. It is found that the highest pressure drag coefficient occurs at α = 90˚ and 270˚ over the whole range of Reynolds number. Results show that the pressure drag coefficient of the cam shaped tube is lower than that of a circular tube with the same surface area for more of the angles of attack.