High Fidelity Tool for Noise Source Identification

Thorough understanding of airframe and propulsion aerodynamic noise sources and the subsequent acoustic propagation to the farfield is necessary to the design and development of efficient, environmentally acceptable aircraft. In this SBIR study, we propose to develop a high fidelity tool using high-order low-dissipation methods in the NASA flagship unstructured CFD code FUN3D. The developed prediction tool can accurately represent the nonlinear flow processes with minimum dissipation, including turbulence, coherent vortices and shock waves critical to the noise generation. Compared to the state-of-the-art unstructured production codes, an increase of one order-of-magnitude in resolvable scales is expected at the expense of just 10% overhead. In Phase I, the effort will include improvement of the 3rd-order scheme for high-aspect ratio unstructured grids, and consistent temporal and spatial accuracies. High-order limiters will be developed to improve the shock capturing capability for sonic boom. The performance improvements will be assessed for the unsteady subsonic and supersonic flows. The Phase II effort will further mature and advance the technology utilizing FUN3D?s massively parallel infrastructure to enable its applications for the prediction of airframe noise sources and the noise sources due to the aerodynamic and acoustic interaction of airframe and engines.