DARPA Helicopter Quieting Program W911NF0410424
Shreyas Ananthan
James Baeder2009
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Abstract
Abstract: A computational framework for coupled aeroelastic analysis of helicopter rotors was developed, tested and successfully validated as part of the HUSH program. The Python-based framework allows the combination of solvers of different disciplines for analysis of different rotorcraft problems in both serial and parallel computing environments. In addition, the framework standardized code interfaces such that multiple codes which have similar functionality can be substituted with ease thereby increasing the spectrum of verification ...
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Theoretical and experimental developments in the aeroelastic and aeromechanical stability of helicopters and tilt-rotor aircraft are addresLed. Included are the underlying nonlinear structural mechanics of slender rotating beams, necessary for accurate modeling of elastic cantilever rotor blades, and the development of dynamic inflow, an urnsteady aerodynamic theory for low-frequency aeroelastic. stability applications. Analytical treatment of isolated rotor stability in hover and forward flight, coupled rotor-fuselage stability in hover and forward flight, and analysis of tilt-rotor dynamic stability are considered. Results of parametri. investigations of system behavior are presented, and correlations between theoretical results Paper presented at the NASA/Army Rotorcraft Technology Conference, NASA Ames Research Center, March 17-19, 1987. * and experiment ,l data from small-and large-scale wlndy unnel and flight testing are discussed.-P ~ (~t A. i * investigations to validate basic theories for beam structural dynamics, unsteady Saerodynamics, and solution methods. Experimental investigations or correlations of aeroelastic tability are not included. In section 3, information about the aeroelastic stabili.y characteristLcs and behavior of rotorcraft is surveyed. hiis includes results of patametric analytical investigations, experimental testing, and correlations to validate prediction AWL_ * 13 * 14 * 16 * *29
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The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information.
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Journal of the American Helicopter Society, 2006
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