Numerical simulation of unsteady rotor-fuselage aerodynamic interaction

A three-dimensional Euler flow solver is developed for the simulation of unsteady rotor-fuselage interaction aerodynamics using unstructured dynamic overset grids. The overset grid system consists of two parts, namely, rotational grid and static grid, and the rotational grid rotates with the rotor while the static grid keeps static during the calculating process. Two overset grids are from the initial integral grid, and the hole fringes are formed and donor elements for hole fringe points are found at the beginning of grid partition. An appropriate overlapping area can be ensured during the unsteady calculation process, and the hole fringe needn't to be formed repeatedly. An efficient searching method is used to update the donor elements at every physical time step, which can reduce the computational effort. The linear spring analogy is used in the rotational grid to treat the flapping and pitching movement of blades. A validation is made by simulating Georgia Institute of Technology configuration rotor-fuselage interaction flowfield and the calculation results agree well with experimental data.