Simulation of flow about flapping airfoils using a finite element incompressible flow solver

Abstract

A finite element flow solver based on unstructured grids is employed for studying the unsteady flow past oscillating airfoils. The viscous flow past a NACA0012 airfoil at various pitching frequencies is simulated. The variation of the force coefficient with reduced frequency is compared to experimental and numerical studies. The effect of variation of the amplitude of the pitching motion on the force coefficient shows that the critical parameter for thrust generation is not the reduced frequency but the Strouhal number based on the wake width. The flow about the airfoil in a combined pitching and heaving motion, a mode found in many insects, is also simulated.