Predicting Pressure Fluctuations in Large Eddy Simulations Using the Immersed Boundary Method

An immersed boundary (IB) method for Large Eddy Simulations (LES) is developed and applied to the turbulent flow around an airfoil. The numerical procedure is based on the use of local mesh refinement to achieve high resolution in the turbulent boundary layer. The primary objective of the paper is to evaluate the accuracy of the wall-pressure spectra predictions. This is relevant for predicting the noise generated by the airfoil. The influence of the IB wall treatment is investigated by applying different reconstruction schemes; in particular, an interpolation method corrected to enforce global mass conservation is introduced and tested. The computed wall- pressure spectra as well as averaged flow fields are compared to experiment and to previous LES simulations carried out using a body-fitted mesh.