Механика жидкости: открытый доступ

Numerical and Experimental Study on the Ability of Dynamic Roughnessto Alter the Development of a Leading Edge Vortex

Abstract

Christopher D Griffin*, Wade W Huebsch, Alric P. Rothmayer and Jay P. Wilhelm

Both computational fluid dynamics, using two- and three-dimensional commercial flow solvers (FLUENT), and experimental analysis (Particle Image Velocimetry) were used to document the ability of sub-boundary layer oscillating surface perturbations (dynamic roughness) to alter the development of a leading edge vortex (LEV) on an airfoil undergoing dynamic stall. The ability to delay or instigate LEV development can potentially lead to methods that can take advantage of the sustained lift while limiting the consequences associated with the shedding of the vortex. Both computational and experimental results show the ability of dynamic roughness to alter the development of a LEV on a rapidly pitching airfoil. Computational simulations were performed in a Reynolds number range from 25,000 to 50,000 at a reduced frequency of 0.1, while experiments included this range as well as runs up to a Reynolds number of 200,000 and reduced frequencies of 0.1, 0.15, and 0.2. The lift-to-drag ratio was increased by approximately 60% at 15° AOA.