Influence of Blade Geometric Parameters on Aeroelastic Response of a Helicopter Rotor System
Publication: Journal of Aerospace Engineering
Volume 26, Issue 3
Abstract
Rotary wing aeroelasticity is a highly complex phenomenon involving coupling between flexible blade dynamics and unsteady aerodynamics including stall and unsteady wake effects. In this paper, a low-cost computational aeroelastic model including the structural coupling from geometric parameters and nonlinearities associated with structural modeling and dynamic stall, applicable to steady, level forward flight, has been developed. The differential equations of motion are solved in time domain in a sequential manner to obtain the response of all the blades in the rotor system, the dynamic inflow variables, and the sectional loads at every time step. A fourth-order Runge-Kutta integration scheme has been adopted for solving the differential equations. Iterations are carried out until convergence is achieved in blade response and helicopter trim. The effect of blade geometric parameters such as pretwist, hinge offset, and torque offset on aeroelastic response of a helicopter rotor system is investigated numerically. It is shown that the structural coupling from blade geometric parameters significantly influences the rotor blade response and loads.
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Acknowledgments
The author acknowledges the research support provided by the Department of Science and Technology (DST), India, and Brain Korea 21 (BK21), Korea.
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Information & Authors
Information
Published In
Journal of Aerospace Engineering
Volume 26 • Issue 3 • July 2013
Pages: 555 - 570
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Sep 5, 2010
Accepted: Sep 26, 2011
Published online: Sep 28, 2011
Published in print: Jul 1, 2013
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