| Helicopter rotor aeroelastic response numerical integration is the basis for stability analysis and dynamic load prediction. Rotor aeroelastic comprehensive analysis model is a typical non-linear and periodic time-varying systems which solution procedure is very complicated. The most commonly used methods such as direct integration Newmark method, HHT law etc are not gratifying in the accuracy and stability, which may cause inaccurate results by reason of numerical oscillation, dispersion, or dissipation of difference schemes. Frequently, it is very difficult to achieve convergent steady state aeroelastic response solutions.Based on the high-precision integration method(HPIM), a modified and much more precise HPIM scheme(3M-HPIM) is designed by well accounting for the nonlinear and time-varying characteristics of rotor aeroelastic model. Firstly, using the low order Jacobi reformation technique, the original system is reformed to three parts: the linear autonomy system, the time-varying system, and the nonlinear system, withholding all high trunction errors. And so, this reformation is Jacobi equivalent to original system. Then, the time-varying and the nonlinear parts are transformed from the non-homogeneous terms of differential eguation to the Duhamel integral representation of integral equation. And last, according to the properties of exponential matrix kernel function, this study has developed a arbitrary precision Gaussian numerical integration algorithm for the Duhamel integral, and with necessarily Gaussian points forecasting by threetimes polynomial approximation.To verify the effectiveness of this 3M-HPIM numerical integraton scheme, sufficient numerical trials, including strong nonlinear and quickly time-varying systems, have been test and validated. This study finally well verified the effectiveness of 3M-HPIM numerical integraton scheme, with much more precise and more stabile than the most commonly used difference schemes.
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