HYBRID METHOD OF CFD AND PRESCRIBED WAKE MODEL FOR ROTORCRAFT AEROACOUSTICS AND AERODYNAMICS PREDICTION

摘要

This paper explains a hybrid method of computational fluid dynamics (CFD) and prescribed wake model developed at Japan Aerospace Exploration Agency (JAXA). The base CFD code herein is a structured grid Euler solver, , which has intensively been developed for helicopter applications at JAXA. The rFlow3D is a highly versatile CFD code that can numerically simulate flows around helicopter in a wide range of flow conditions, considering trimming and blade elastic deformation. In this study, several existing prescribed wake models are combined with rFlow3D. Accuracy of the hybrid method is evaluated by comparing computational results with experimental ones. Airload coefficient on blade and blade vortex interaction noise contour computed by the hybrid method show good agreement with experiment, however, they are still overestimated since their miss distances are rather short. Thus, we plan to improve the hybrid method by utilizing initial vortex position data obtained from rFlow3D to prescribed wake models in the near future.