Study On Structural Dynamic Of High Aspect Ratio Solar Unmanned Aerial Vehicle(UAV)

The Stratosphere Solar Unmanned Aerial Vehicle has very broad prospects for development in the long term surveillance monitoring, environmental monitoring and communications relay because of its special advantabe. Countries around the world have paied more and more attention to it, which has become one of the national focus on the development of weapons and equipment. Most of such aircraft use of lightweight, high strength and high stiffness of the composite material structure, they all have the high lift to drag ratio with high aspect ratio wing.At present, Domestic for high aspect ratio composite wing structure design mainly focused on the static analysis, research on Dynamics analysis is less, however.In fact, in both loading and unloading, transport, and in the process of launch and flight, aircraft are likely to generate strong vibration and noise, the resonance vibration may stimulate the internal equipment, damaging the structure and equipment, when the UAV flying in high altitudethe wing will produce great bend and torsion deformation. Especially, the aerodynamic loads will affect the redistribution of airfoil aerodynamic load and the whole machine performance, and pneumatic/structure coupling phenomenon. In the near space weak air convection, the internal structure of the operation will inevitably produce disturbance, due to the near space thin air, air damping is small, any even small disturbance are easy to provoke the vibration of the structure. It is difficult to self attenuation if vibration once aroused, therefore, it is necessary to analyze the structural dynamics of high aspect ratio wing.In this context, Based on the British QinetiQ the company developed the "breeze"(Zephyr7) solar UAV, refering to the structure parameters and material properties of the finite element model, We establish the finite element model of UAV, and analyzed its dynamics, and the relationship between changes of the UAV girder, skin, rib structure parameters such as the UAV and vibration.Analyzed different material parameters in the wing of the modal, Found the weak link in the body vibration, and pointed out the wings need to be aware of the problems in the process of design.On the basis of vibration, preliminary assessed the frequency response of single and double fuselage structure. Simulation of twin fuselage body in the sharp edged gust and propeller rotational excitation, the response analysis of structure.Analyzed the net in the process of recycling, hindered the shock response of the wings, to determine the hazardous area of the body structure.