Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : November 12, 2016 - November 13, 2016
The effect of streamwise wave-like wall deformation of a turbulent channel is studied through direct numerical simulations. Here, the simulation was conducted under constant pressure gradient, unlike past studies, which was held under constant flow rate conditions, in order to prevent friction velocity changes before and after the control for concrete discussions on mechanism of drag reduction. Simulations reveal that wall deformation grants approximately 40% drag reduction, due to random component of velocity fluctuation drop and negative periodic Reynolds shear stress.