helicopter blade stability analysis using aeroelastic frequency response functions
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abstract
in the present paper, the aeroelastic stability of helicopter rotor blade is determined using aeroelastic frequency response function. the aeroelastic model of blade is obtained by combining dowell - hodges beam model with loewy unsteady aerodynamic theory which considers an unsteady wake beneath the rotor. equations are formed and aeroelastic frequency response functions are obtained by inverting dynamic stiffness matrix of the aeroelastic system. exciting each degree of freedom, system response could be obtained. the resulted response is then plotted for various blade pitch angles and the behaviour of this function investigated to find out the stability criteria and also system natural frequencies. the results of this method are compared with stability boundaries obtained from the conventional p-k method.
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Journal title:
journal of applied and computational mechanicsPublisher: shahid chamran university of ahvaz
ISSN 2383-4536
volume 1
issue 3 2015
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