An Efficient Tightly Coupled Fluid-Solid Interaction Approach For Modeling Rotors in Forward Flight

摘要

A tightly coupled fluid-solid dynamics interaction approach has been developed for the efficient prediction of aerodynamic loads on rotor blades in forward flight. The aerodynamic computations are done using a 3-D Navier-Stokes solver modeling the viscous flow over the blade and the near wake. The elastic structural dynamic computations are carried out using a multi-body dynamics approach. The fluid and solid dynamics equations are simultaneously integrated in time, providing a tight coupling between the structural dynamic and fluid dynamic solvers at every time step. A generalized grid motion module has been developed to account for the effects of the blade motion and elastic deformations on the aerodynamics. A free self-induced wake model is used to model the tip vortex effects once the blade tip vortices leave the resolved CFD domain. A four-bladed UH-60A rotor at a high advance ratio has been studied, and the results compared with flight test data.