Immersed boundary projection method based analysis of airfoils at very low Reynolds number

A numerical investigation of fluid-structure interaction of airfoils at extremely low Reynolds number (100≤Re≤1000) is carried out in view of the Micro-Air-Vehicle (MAV) application. The immersed boundary projection method (IBPM) is chosen for its ease of solving the system of equations. At such lower values of Re where the viscous forces are dominant, IBPM has been proven to give results of second-order accuracy. The IBPM is validated from literature by performing the simulations of flow over a 2D stationary circular cylinder followed by a grid independence study. The values of lift and drag coefficients for Re=100 were in good agreement with the literature. The investigation is extended to 2D stationary airfoils that resemble the envelope of insect wing structures in view of MAVs' application. The lift and drag characteristics of the selected airfoil at the angle of attack 0° and 10° at various Re were studied. The lift/drag ratio of the selected airfoil for the application of MAVs shows the airfoil's load-carrying capacity at low Re, which usually represents the payload-carrying ability of these MAVs.