THE ANALYSIS OF THIN WALLED COMPOSITE LAMINATED HELICOPTER ROTOR WITH HIERARCHICAL WARPING FUNCTIONS AND FINITE ELEMENT METHOD
【摘要】：正 In the present paper, a series of hierarchical warping functions isdeveloped to analyze the static and dynamic problems of thin walled composite lami-nated helicopter rotors composed of several layers with single closed cell. This methodis the development and extension of the traditional constrained warping theory ofthin walled metallic beams, which had been proved very successful since 1940s. Thewarping distribution along the perimeter of each layer is expanded into a series of suc-cessively corrective warping functions with the traditional warping function causedby free torsion or free bending as the first term, and is assumed to be piecewise linearalong the thickness direction of layers. The governing equations are derived basedupon the variational principle of minimum potential energy for static analysis andRayleigh Quotient for free vibration analysis. Then the hierarchical finite elementmethod is introduced to form a numerical algorithm. Both static and natural vibra-tion problems of sample box beams are analyzed with the present method to show themain mechanical behavior of the thin walled composite laminated helicopter rotor.