Navier-Stokes Simulation of a Rotor Using a Distributed Pressure Disk Method

An incompressible Navier-Stokes code was modified to model the effects of a helicopter mtor on the viscous aerodynamics of the fuselage. The rotor was treated in a manner similar to an actuator disk, with tbe thrust being modelled as a jump in pressure across the disk. Unlike an actaator disk, the pressure jump was allowed to vary with radial aud azimuthal locations on the disk and was computed from a fully coupled blade element model. Swirl velocities were implemented by adding a jump in tangent velocity across tbe disk surface. Chimera grids were used to allow more complex configurations to be modelled. Calculations were made for an isolated rotor as well as for a rotor/fuselage geometry and compared with experimental inflow velocity data and experimental fuselage surface pressure data. The time-averaged effect of the rotor on the fuselage as well as the time-averaged effect of the fuselage on the rotor are shown.