弹性飞机平衡的阵风外载荷计算与分析

连续紊流是适航规范中阵风载荷分析必须考虑的一种阵风模型,但其引起的阵风载荷在飞机结构设计中的应用一直存在困难.在平稳随机过程的假设下,基于von Karman连续紊流功率谱模型和线性系统连续紊流响应的功率谱方法,使用载荷累加法获得外载荷形式的阵风载荷.在此基础上,通过引入载荷响应的相关性推导并建立了一种生成多组连续紊流平衡外载荷分布的方法.垂向连续紊流情况下的算例结果表明:连续紊流外载荷分布是全机平衡的.平衡的外载荷分布可通过机动飞行载荷分析中的载荷包线方法识别载荷设计情况,从而应用于飞机结构的强度分析与设计.

Balanced external gust loads computation and analysis for elastic aircraft

Continuous turbulence is one of gust models for gust loads analysis needed in various aviation regulations.But there exit some difficulties when the loads induced by continuous turbulence applied to aircraft structural design.Based on stationary random process assumption,utilizing power spectral density(PSD) method and von Karman continuous turbulence model,external gust loads were obtained by using force summation method.An approach was presented by introducing correlations and multiple sets of external load distributions due to continuous turbulence was generated.The results from an elastic aircraft encountering vertical continuous turbulence demonstrate that the external gust load distributions are strictly in banlance.These load distributions can be applied to structural stress analysis or design when the design conditions are identified through load envelope concept which is frequently applied in maneuvering flight loads analysis.