Direct numerical simulation of turbulent channel flow over a rough wall with uniform blowing (UB) for drag reduction has been performed to have our understanding of UB toward practical applications. It turns out that UB is applicable to rough materials as well as, or possibly better than, ideal smooth ones. The drag reduction rates achievable with UB are smaller in the rough case but the amount is larger. In addition to the conventional friction drag reduction mechanisms by UB, i.e., moving the turbulent structures outward, pressure drag, which does not appear on the planar wall, is suppresed as well due to the supression of stagnation.
|Titolo:||Direct Numerical Simulation of Drag Reduction with Uniform Blowing over a Rough Wall|
|Data di pubblicazione:||2016|
|Appare nelle tipologie:||04.1 Contributo in Atti di convegno|