| Modern helicopter rotor systems are increasingly using composite materials,and composite rigid blades and bearingless rotors are also important directions for helicopter development.The application of rigid rotors on helicopters and compound helicopters at variable speed long-haul flights has the advantage of improving the forward speed of the helicopter and improving flight performance.In this paper,a composite rigid rotor structure is studied,and its structural components are mostly composed of composite materials.Firstly,the VABS-based beam profile analysis method is analyzed,and the calculation process of beam profile stiffness analysis is established.The correctness is verified by an example.The influence of fiber layup angle on the section stiffness of composite beams is discussed,which provides a theoretical basis for the laying design of blade assembly fibers.In the blade design,the basic shape geometric parameters and section structure of the blade are preliminarily determined,the composite layer layup angle of the blade assembly is set,and the composite material mechanics is used to analyze the composite material characteristics.The dynamic characteristics of the blade are analyzed by finite element software,and the first-order waving frequency of the blade is greater than 1.2 by the frequency modulation design,and the first-order stress of the shim is greater than 1.3,so that the blade meets the inherent characteristics of the rigid rotor.The effects of different fiber materials and different fiber volume ratios on the natural frequency of the blade were analyzed.The hub structure of the rigid rotor is designed,and the dynamic characteristics of the finite element are analyzed to meet the design requirements.The rotor assembly is then intensity checked to meet the strength requirements of the assembly.The LMS modal analyzer was used to measure the natural mode of the model blade,and the dynamic characteristics of the designed model blade were verified. |
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