Aeroelastic Modeling And Analysis Of The Near Space High-Aspect-Ratio UAV

Because of the near space high-aspect-ratio unmanned aerial vehicle's super altitude long endurance cruising flight characteristic, it was use as a small satellite for scout and communication in the future war. Along with the related technique's development, the research on near space high-aspect-ratio UAV become a hot topic. Among the key techniques of near space high-aspect-ratio UAV, elastic model's establishment is of great importance. Building the model of the near space high-aspect-ratio unmanned aerial vehicle is a challenging work duo to the complexity of the couple between aerodynamic and structure. This paper took modeling as the main research content, and analyzed /restrained the phenomena of aeroelasticity based on the model. The major research work of the paper are as follows:1. Building the aeroelasticity model of the near space high-aspect-ratio UAV based on Lagrange function and strips theory. Different from the current method which use Hamilton principle to obtain structure model firstly and then attain the state space equation through discretization, this paper derived the state space equation of the near space high-aspect-ratio UAV through Lagrange equation, and then took generalized aerodynamic express the couple between aerodynamic and structure deformation. In view of the fact that most of the high-aspect-ratio wings are straight-wings or have small sweepback, the aerodynamic model was built based on strips theory and Theodorsen aerodynamic. Comparing with the current method, this method was used in the paper reasonably simplified the calculation.2. Deriving the small perturbation linearization function of the near space high-aspect-ratio unmanned aerial vehicle in the work point, and analyzing its longitudinal characteristic under the perturbation condition of gust wind.3. Restraining the wing's flutter which is caused by gust wind. The restrain system designed by this paper eliminated the wing's flutter ,arrived at a stable state, and availably restrict the instability of airframe's longitudinal motion caused by wing's flutter.