大型民用飞机尾旋运动的系统辨识研究

Systems Identification Research of a Large Spin Motion for Civil Aircraft

为了研究某常规布局大型民用飞机的尾旋特性,首次利用一个满足动力相似的缩比模型在Ф5m尾旋风洞中进行研究试验,利用机载传感器所采集的模型运动参数来研判飞机模型的尾旋特性。目前,对于此类飞机模型尾旋运动中所承受的气动力矩研究还十分缺乏,以飞机模型尾旋试验结果为基础,采用飞机六自由度运动学方程来还原模型在尾旋运动中所承受的气动力矩系数,同时利用常规风洞测力试验结果来检验所还原的气动力矩系数的可靠性。进一步采用多元高次方程对模型尾旋运动进行了系统辨识研究,建立了能辨识飞机在尾旋运动条件下的气动力矩系数的数学模型,成功的辨识了重要的气动力系数的导数(C_(mα),C_(mδe),C_(mq),C_(nβ),C_(nδr),C_(nr),C_(lβ),C_(lδr),C_(lp)),与相关参考值比较显示其结果具有较高的可信度。

A dynamic similarity scaled aircraft model was tested in spin tunnel to investigate spin characteristics of a large civil aircraft in first time. The spin characteristic of aircraft model was investigated based on kinematic pa- rameters which was recorded by sensors. The research on aerodynamic moment which acts on the aircraft model in spin motion is still very absent. Base on results of the large civil aircraft model free-spin test, aerodynamic moments were calculated by six degree freedom equation of motion, reliability of calculated results were validated by the comparison with results of force measurement of aircraft model in normal wind tunnel in this paper. Finally, system identification research of aircraft model spin motion was carried out, multivariate polynomial equation was used. The mathematical model which can be used to identify the moment coefficients was created, several important aerodynamic derivative was identified, such as Cmα,Cmδe,Cmq,Cnβ,Cnδr,Cnr,Clβ,Clδr,Clp. These derivatives were validated by the reference value.