Determination of flutter derivatives by a taut strip model

The taut strip model is a kind of aeroelastic model, which can be regarded as an in-between model between the sectional model and the full aeroelastic bridge model. Determination of flutter derivatives by taut strip models has rarely been studied. In this paper, a theory of determination of flutter derivatives using the taut strip model is established based on the eigensystem realization algorithm. Considering the restriction of measuring points, modal coordinate expansion technique is introduced to get the information of unknown measuring points. Generalized inverse matrix theory is employed to obtain the stiffness matrix and damping matrix of taut strip models. Then, the flutter derivatives can be extracted by the subtraction of stiffness and damping matrixes. A method of identifying of flutter derivatives in turbulence flow is also proposed through the random decrement technique. Experimental study of determination of flutter derivatives by taut strip model is carried out based on the theory discussed in the paper. A taut strip model of a thin plate is designed, and it is used in smooth flow to determine flutter derivatives as well as in turbulence flow in TJ-2 wind tunnel of Tongji University. In the end, comparisons with theoretical flutter derivatives of a thin-plate section are undertaken to validate the reliability of the theory.