Modeling of interior nozzle flows for transient effects, realistic high performance nozzle physics and coupling to Large Eddy Simulation modeling of t

The objective of the present proposal is to develop and apply accurate, robust and cost-effective methodologies for the prediction of the interior nozzle flow, seamlessly coupled with high-fidelity large eddy simulation (LES) for the prediction of the jet plume and radiated noise. The simulations will be performed in the massively-parallel unstructured LES framework developed at Cascade Technologies, using our flagship compressible solver Charles. In Phase I and I option, the proposed tasks focuses on near-wall adaptive mesh refinement, synthetic inflow turbulence and wall modeling inside the nozzle. In particular, the wall model will significantly reduce the computational cost by relaxing the grid resolution requirements in near-wall region inside the nozzle. In addition, physics-based mesh refinement and adaptation will be implemented. This automatic meshing approach has the potential to not only greatly simplify the meshing process and drastically reduce the burden on users, but also to improve accuracy while reducing the simulation run time. The impact of these additional modelings on the predictive capability of LES must be characterized and best practices must be developed. This proposal describes a scope of work that includes development, implementation and testing of these capabilities for complex jet configurations relevant to the Navy.