基于虚拟质量的飞机颤振快速分析方法

Fast Analysis of Aircraft Flutter Based on Fictitious Mass Method

王斐 冉玉国 李秋彦

WANG Fei RAN Yuguo LI Qiuyan

航空工业成都飞机设计研究所, 四川 成都 610091

AVIC Chengdu Aircraft Design and Research Institute, Chengdu, Sichuan 610091, China

针对研制初期，飞机结构设计参数存在严重不确定性，颤振设计工作难以快速有效推进的问题，开展了方案设计阶段飞机颤振快速分析方法研究。采用虚拟质量法，通过在原结构一定位置施加虚拟质量，建立可覆盖局部结构参数变化的统一模态振型，然后将此虚拟质量从质量矩阵中移除，以防止影响原结构的动力学特性，并采用虚拟质量模态振型对不同参数下的质量矩阵、阻尼矩阵、刚度矩阵以及气动力矩阵进行广义化，建立虚拟质量模态空间下的颤振方程，并采用法求解，得到不同参数下的飞机颤振速度。建立了一种飞机颤振快速分析方法，在面对大量参数开展敏感性研究分析时，能有效减少模态分析次数，提高飞机方案设计阶段分析效率。通过算例对比分析可知，该方法计算精度与传统方法基本一致，满足工程需求。

Aiming at the difficulties in flutter design due to uncertainties of structural parameters for the initial stage of aircraft design project, the research on the aircraft flutter rapid analysis method in the planning stage is carried out. The fictitious mass method is applied to create a uniform mode shape that can cover the changes of local structural parameters. Then the fictitious mass is removed from the mass matrix to avoid affecting the dynamic characteristics of the original structure. The mass matrix, damping matrix, stiffness matrix and aerodynamic matrix under different parameters will be generalized with this mode shape. The flutter equation in the fictitious mass modal space is established, which is solved by the method, and the flutter velocity of the aircraft with different parameters is obtained. In this paper, a fast analysis method of aircraft flutter is established, which can effectively reduce the work load of modal analysis and improve the efficiency of aircraft scheme phase analysis when carrying out sensitivity analysis in the face of a large number of parameters. Through the comparative analysis of examples, it can be seen that the calculation accuracy of this method is basically consistent with the traditional method, which meets the engineering needs.

10.11885/j.issn.1674-5086.2020.09.10.01