Time-accurate simulations and acoustic analysis of slat free shear layer

A detailed computational aeroacoustic analysis of a high-lift flowfield is performed. Time-accurate Reynolds averaged Navier-Stokes computations simulate the free shear layer that originates from the slat cusp. Both unforced and forced cases are studied. Preliminary results show that the shear layer is a good amplifier of disturbances in the low- to midfrequency range. The Ffowcs Williams and Hawkings equation is solved to determine the acoustic field using the unsteady flow data from the Reynolds averaged Navier-Stokes calculations. The noise radiated from the excited shear layer has a spectral shape qualitatively similar to that obtained from measurements in a corresponding experimental study of the high-lift system.