Aerodynamic Evaluation of Miniature Trailing-Edge Effectors for Active Rotor Control

This work presents progress on a detailed aerodynamic evaluation of Miniature Trailing-Edge Effectors (MiTEs) for active rotor control. We begin with a 2D computational fluid dynamics (CFD) study focused on establishing the dependency of MiTE effectiveness and performance upon basic geometric parameters on a VR-12 airfoil. The CFD study demonstrated that a MiTE placed at 10% chord upstream of the trailing-edge and sized at approximately 1% chord is capable of delivering moment coefficient increments of approximately ±0.03, or the same moment authority as a conventional flap moving ±2.3 degrees. Wind tunnel experiments were performed on a model blade section equipped with an operational MiTE in order to validate the CFD results, and strong agreement was shown. Finally, a small set of 3D unsteady CFD simulations with prescribed blade motion of a rotor equipped with MiTEs were performed. Under high-thrust, moderate speed conditions, MiTEs deployed sinusoidally at 4/rev frequency were capable of reducing 4/rev integrated aerodynamic loads in the vertical direction by approximately 80%.

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