Gas Turbine Engine Noise Modeling

Jet noise mitigation techniques are currently under evaluation by CRAFT Tech and NCPA for application to the F/A-18 E/F aircraft. Varied passive technologies, e.g. microjet blowing, corrugations, etc. analyzed at 1/10th scale culminated in full-scale propulsion stand tests of a F404-400 engine during Summer 2004. Under this proposed SBIR, an "End-to-End" Aircraft Noise Footprint Model will be developed for application to military gas turbine engines. The model interfaces CRAFT Tech' state-of-the-art aircraft plume CFD modeling with well-validated, systems level farfield noise propagation modeling to create a high-fidelity capability for evaluating environmental impact of noise emissions from military gas turbine engines and to enable analysis of potential noise reduction technologies, as well as operational changes. The proposed modeling will integrate noise propagation with topographical data to enable the Navy to generate noise contour maps around naval facilities that are intended to receive the Joint Strike Fighter (JSF). The Phase I effort will provide a demonstration of the model for JSF, as well as its demonstration for evaluating design/operational changes consistent with the requirements of military gas turbine engines. A detailed sub-scale test plan will also be developed for obtaining relevant noise data during Phase II to support model validation and refinement.