Hybrid RANS-LES Simulation of Separated Nozzle Flow

Asymmetrical separation of a severely overexpanded supersonic nozzle flow can cause un- wanted lateral pressure forces, or side-loads, acting on the nozzle structure. Some empirical models for side-load estimation exist but provide only moderate accuracy. Computational Fluid Dynamics methods have improved in recent decades through advances in turbulence modeling and improvements in computing technology. Several past efforts have been made toward a more accurate side-load predictions through Computational Fluid Dynamics sim- ulations and and the current study aims to add to that knowledge base by exploring the capability of a Delayed Detached-Eddy Simulation employing the k−e turbulence model to simulate an overexpanded nozzle flow and provide a good side-load estimate. The results are promising with side-load levels comparable with experimental data although further development is needed.