Coupled Experimental and Offline Simulation Study of a Helicopter Rotor in a Frigate Airwake with Active Flow Control

Abstract

The operation of helicopters from small naval vessels like frigate present a demanding challenge for pilots. This paper studies the effect of active flow control system located along the sides of the hangar edges on the unsteady aerodynamic loads of a scaled rotor model operating along a stern approach. The flow field above the helideck is experimentally measured using stereo particle image velocimetry. These data are compared to ship airwake computations to assess the flow prediction capabilities. The ship airwake in headwind and G20 conditions without and with blowing are implemented into the Airbus Helicopters HOST simulation code based on the one-way coupling approach. The output data are equilibrium monitoring curves of the four commands states. The deviations induced by blowing are in the order of 1% to 25% and it allows at bringing the commands back to the uncontrolled airwake case.