To analyze the aeroelasticity of rotor with trailing edge flap(TEF) in forward flight, a high-precision computational CFD/CSD coupling method is established. A set of rotor moving-embedded grid method with TEF is developed by parametric method. In aerodynamic analysis, based on the traditional aerodynamic model, the high-precision CFD method is introduced to accurately simulate the unsteady flow field and aerodynamic characteristics of the rotor. In structural aspect, the dynamic model of rigid TEF is established, the influence of the motion of the rigid TEF on the rotor system is considered in the form of additional mass, damping, stiffness and other matrices, the nonlinear mo-tion equation of the rotor system is derived based on Hamilton’s principle and Timoshenko beam model. An elastic grid deformation method based on algebraic transformation is adopted, and the unsteady fluid-solid coupling strat-egy is developed. By comparing the results of the aeroelastic loads of the model rotor and the SA349/2 rotor, the effectiveness of the CFD/CSD coupling method is verified. On this basis, taking the SMART rotor with TEF as an example, the results of the equivalent normal force coefficient of the blade sections are compared. Emphasis is placed on the analysis of the Fulton model rotor, studying the variation of blade root torque in hover and flap mo-ment amplitude in forward flight, and comparing them with literature results. The results show that the CFD/CSD coupling method established in this paper can improve the analysis accuracy of the unsteady aeroelastic load of the rotor, and accurately capture the BVI phenomenon of the low-speed forward flight rotor, the average error of flap bending moment is controlled at 11.68%; At the same time, the error of the natural frequency of the blade with TEF is less than 4.0%, and the average error of flap bending moment amplitude of blade root is 15.15%, which can ef-fectively simulate the aeroelastic characteristics of the TEF.
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