The Flutter Analysis Of High Ratio Ring Based On Parametic Modeling

The parameterized design thought is mainly used for the structure design, this paper willtry to use parametric method to establish the finite element model of high aspect ratio wing.Because of its stiffness is low, it will produce the large torsion deformation easyly and thenflutter in the aerodynamic load. This paper will show different sweep aspect ratio wing flutteranalysis, in order to get the effect of sweep angle on flutter, providing reference forengineering application.Select the " Predator " unmanned aircraft as the prototype, then simplify it geometrymodel contains the main parameters. Establishes the relationship between the mainparameters in the CATIA, and use VB to develop an interface to achieve the automaticmodeling, in order to improve the efficiency of design.According to the characteristics of finite element analysis process is time consuminedamong flutter analysis, puts forward the structure finite element wing parametric modelingmethod. Construct driving method based on fast finite element modeling, and take parametricdescription of the geometry mesh model and finite element model, so that realise the creationand updation of finite element modelautomatically, greatly improving the speed, precision andmodeling the degree of standardization.In this paper, there will be flutter characteristics analysis of high aspect ratio ring at thespeed of subsonic in high-altitude. Firstly,evaluated the natural frequency of the model, basedon doublet lattice method establish lifting surface plate grid model, with beam spline on thelift surface element interpolation, at last finish the establishment of aeroelastic model.Compare the the flutter speed and frequency under different Maher numbers and differentsweep, respectively, analysis suggests that the increase of Maher number will reduce the flutter speed and frequency, sweep must consider the effect of tangential component in morethan45degrees, sweep increases will increase flutter speed.