Finite Difference Numerical Prediction of Aerodynamics of Airfoil Flying over Wavy Wall

Abstract

The lift on an airfoil flying over a wavy wall surface is calculated using a finite difference method, which was developed by J. Nakamichi to improve LTRAN2 evolved by W. F. Ballhaus and P. M. Goorjian. Numerical computations include cases of a flat plate over a flat solid wall prior to the cases of a moving wavy wall. Modification of grid generating system is the major point for applying the LTRAN2 version to our problem. The weak compressibility (M_∞=0.1-0.3) is considered but nonlinearity is neglected in our calculations. The calculated results are compared with those obtained by the lifting surface theory of M. Ichikawa et al. The agreements are quite satisfactory.