3种气动弹性状态空间建模方法的对比

研究气动弹性状态空间建模的3种常用方法:最小二乘(LS)法、最小状态(MS)法和拟合状态空间(MA)法.用2个算例从颤振和频响特性角度分析和总结了它们的建模特点.在气动力有理函数拟合建模方法(LS法、MS法)研究中,着重分析滞后根的影响;在MA法的研究中,讨论了建模的特点.最后,系统对比了3种建模方法的建模效果及使用原则,为这些方法的工程应用提供参考.仿真计算结果表明,MS法建立的模型阶数低、精度适中且使用方便,是比较好的方法,而MA法建立的模型频响特性与参考结果最为接近.

Comparison of Three Aeroelastic State-space Modeling Methods

Three methods used for aeroelastic state-space modeling are discussed in this paper. They are least square (LS) method, minimum-state (MS) method and fit state-space approximation (MA) method. The modeling characters of these methods are analyzed and summarized through two models, according to flutter and response of frequency respectively. In the research of rational function approximation methods (LS and MS methods) on aerodynamic forces, the effects of lag root are highly analyzed. The character of MA method is also discussed. Finally, the modeling effects and utilizing principles are compared integrally, which then could be considered as assistance to engineering applications. The simulation results indicate that the MS method, used conveniently, is the preferable one which can generate models with low order and appropriate accuracy. The model founded on MA method gives the best accuracy of response of frequency, as compared with that of the standard result.