Clockwise Vortical-Gust/Airfoil Interactions at a Transitional Reynolds Number
Clockwise Vortical-Gust/Airfoil Interactions at a Transitional Reynolds Number
复制标题
过渡雷诺数下的顺时针涡旋阵风/机翼相互作用
作者:
C. Barnes;M. Visbal
This paper presents high-fidelity implicit large-eddy simulations (ILES) of parallel vortical gust interactions with a NACA0012 airfoil operating at a transitional chord-based Reynolds number of Rec=200,000 and an angle of attack of α=4 deg. The gust is supplied upstream of the airfoil as a Taylor vortex. Three different initial vertical positions are considered for a clockwise (CW)-oriented gust. ILES simulation of CW gust interactions is compared with inviscid simulations as well as prior counterclockwise (CCW) gust simulations. Contrary to the previous CCW gust interactions, the upper surface boundary-layer experiences an upstream excursion of laminar separation, transition, and turbulent reattachment that lingers behind the gust. This upstream shift manifests in a pitch-up moment coefficient that relaxes slowly to the pregust state. As in the previous CCW cases, the lower surface boundary layer is disrupted by the CW vortex producing a brief acoustic event. This effect is particularly severe when the...