Prediction of Moment Using a Modified Discrete Vortex Method in Ground Effect

Abstract

The aerodynamics around a wing is modified when it comes near the ground. This is generally referred to as ground effect. In this work, a discrete vortex method based model which can predict two-dimensional (2D) ground effect from its free flight data is proposed. The required data in free flight could be generated either from high fidelity CFD solver or experiments. In this method, strength of the vortex distribution as obtained from discrete vortex based method is modified using a constrained optimisation procedure to match the free flight aerodynamic data. This vortex distribution is further modified due the presence of the ground. The efficacy of present model is demonstrated for predicting the moment of multi element airfoils in ground effect. The predicted aerodynamic coefficient in ground effect compares well with high fidelity CFD data.