Use of symbolic regression for construction of reynolds-stress damping functions for hybrid RANS/LES

Abstract

A novel approach to turbulence model development is applied to formulate a Hybrid RANS/LES methodology suitable on coarse meshes. The Reynolds-stress damping function in the Flow Simulation Methodology (FSM) framework is difficult to formulate rigorously from first principles, however it is critical to the success of the model. The damping function dictates locally and instantaneously the contribution level of a RANS model required to supplement structures resolved by the grid. The current formulation is a damping of the turbulent length scale in a nonlinear explicit algebraic stress RANS closure. This turns the eddy viscosity into a sub-grid scale model. In this proposal Symbolic Regression..