Lift characteristics of pitching NACA0015 airfoil due to unsteady forced surface inflation

Abstract

The purpose of this work is to investigate the unsteady forced surface inflating (UFSI) effect on lift coefficient of a pitching airfoil. Thus, 2D unsteady compressible flow around a pitching airfoil is analyzed by means of coarse grid CFD (CGCFD) method and spring dynamic grids network. At first to validate the code for moving boundary cases, the predicted lift coefficient of pitching airfoil is compared with experiments. Simultaneously, the CGCFD results are compared with the RANS simulation. Then UFSI is added to the pitching airfoil. The effects of unsteady parameters such as the inflation amplitude and phase difference between pitching and inflation is investigated on lift and pressure coefficients of pitching airfoil. According to the results, UFSI, with zero degree phase difference between pitching and inflation, help to postpone the dynamic stall.