Study of the laminar flow around a solid that subjected to vibratory movement

Abstract

In this work, our main goal is to study the effects of the vibratory movement of an airfoil on the aerodynamics. This type of studies can help improving the design of micro air vehicles (Mavs). For flapping wings, efforts are made to improve our understanding of the unsteady fluid physics on the mechanism of generation of lift at low Reynolds number. This thesis concerns only on the hovering flight mode which means no free flow applied on the structure. Two types of hovering mode were studied "Water treading" and "Normal" mode under different Reynolds number (Re=75, 100, 900, 1700), which is interesting to identify favorable parameters from aerodynamics viewpoints to develop suitable strategies for more efficient design of micro air vehicles. A finite element method was used to simulate the flow field using a commercial software called Ansys . The analysis shows that, the leading edge vortices and the rapid pitch-up mechanisms are responsible for most of the lift generation at a Reynolds numbers of 100, 900 and 1700, but only for the Normal hovering mode the mechanism of the wake capture influences the lift generation by creating two picks.