Direct numerical simulation of turbulent boundary layer over a compliant wall

Abstract

The performance of compliant wall with different parameters in a spatially developing turbulent boundary layer is investigated by direct numerical simulation. The Reynolds number based on the external flow velocity and the momentum thickness ranges from 300 to approximately 860. The compliant wall is placed in the region starting from 200 to 600 in the streamwise direction, scaled by the inlet momentum thickness. The monoharmonic analysis is carried out for selection of the parameters of compliant wall in numerical simulations. The instantaneous flow fields and the turbulence statistics are presented to show the impact of the compliant wall. A dynamical decomposition of the skin-friction coefficient Cf is performed for examining the sources bringing the variations in Cf. The spatial evolution of compliant wall motion is disclosed, which is a special feature of the boundary layer flow. The spatial–temporal self-correlation of the wall displacement is calculated for obtaining the convection velocity of the wavy motion of compliant wall. The frequency–wavenumber power spectrum of wall pressure fluctuation is presented for studying the interaction of the compliant wall and the above turbulent flow. The effect of the fixed boundaries of the compliant wall is also examined.