A Model Form for Reynolds Stress Decay Informed by Analysis of Anisotropically Forced Homogeneous Turbulence

Reynolds-averaged Navier-Stokes models are a popular toolset for predicting complex turbulent flows due to their computational affordability and ability to provide quantities of engineering interest. However, results are sensitive to the treatment of unclosed terms, which require further modeling. The Reynolds stress transport equation provides a detailed framework for evaluating these unclosed terms. We focus on the decay terms in the Reynolds stress equation, which can be isolated and evaluated separately from other terms using the canonical case of homogeneous turbulence. We perform a wide range of turbulence resolving simulations with anisotropic forcing to enable a robust selection of model form and coefficients. Performance of the selected decay model is then examined relative to the simulation data and popular models from the literature.