Pressure Loss and Heat Transfer Characterization of a Cam-Shaped Cylinder at Different Orientations

Pressure drag coefficient and heat transfer are experimentally investigated around a single noncircular cylinder in cross-flow under angle of attack $0deg<α<360deg$ and Reynolds number $1.5×104<Reeq<4.8×104$ based on equivalent diameter of a circular cylinder. The results show that the trend of pressure drag coefficient against the angle of attack has a wavy shape but the wavy trend of the Nusselt number is smoother relative to the drag coefficient behavior. It is found that for $l∕Deq=0.4$ and over the whole range of the Reynolds number, the pressure drag coefficient has a minimum value of about $CD=0.4$ at $α=30deg$⁠, 180 deg, and 330 deg and a maximum value of about $CD=0.9$ at $α=90deg$ and 270 deg. The corresponding value of the mean Nusselt number to that of the equivalent circular tube is $1.05<Nu¯cam∕Nu¯cir<1.08$ at $α=90deg$ and 270 deg as well as $0.87<Nu¯cam∕Nu¯cir<0.92$ at $α=30deg$ and 180 deg.