Prediction of unsteady pressure and velocity over a rotorcraft in forward flight

Abstract

The problem of predicting the periodic three-dimensional vortex-dominated flowfield around a rotorcraft in low-speed forward flight is studied using potential-flow methods, whose results are compared with surface pressure measurements and flow velocity measurements. The test case used is a two-bladed teetering rotor above a hemisphere-cylinder airframe in a wind tunnel. The dominant features of this problem are modeled by a lifting-line/lifting-surface rotor model with a free wake distorting in the presence of the airframe