Large-Eddy Simulation Combined with the Stability Theory for Turbulent Transition Prediction

Abstract

Large-eddy simulation (LES) with the stability theory is developed for the high-fidelity and cost-effective simulation of turbulent transition. This study comprises three main parts. First, the LES framework is validated for a canonical transition scenario. The parabolized stability equations (PSE) is coupled to LES in order to provide major instability modes in a pre-transition region. Second, three sub-grid-scale (SGS) models are investigated for the transition regions, because most SGS models have been developed for purely turbulent flow. The three SGS models are theoretically and computationally studied. Third, once the PSE-coupled LES method is validated, the method is used in a transition control study. The phase of two major instability modes is modulated here. The current study indicates that the phase modulation has a great potential to delay the transition significantly.