基于气弹模型风洞试验研究张拉膜结构气动参数

基于两种鞍型张拉膜结构的气弹模型风洞试验,分别采用Ibrahim时域法和随机子空间参数识别法从自由响应及风荷载作用下响应的数据中识别了结构的模态参数.在此基础上,研究了气动质量及气动阻尼随风向角、风速、预张力的变化规律,并通过与前人研究成果的对比分析了各研究成果之间差别产生的原因.研究结果表明,气动质量会随风向角的变化而变化且在斜风向下时达到极值,随风速的增加而增加,随预张力的增加而减小;第一阶模态所对应的总阻尼比随风速的增加而增加.

Aerodynamic Parameters of Tensioned Membrane Structure Based on Aeroelastic Wind Tunnel Test

Based on aerodynamic wind tunnel test of two saddle tensioned membrane structures, the modal parameters are identified from free responses and responses under wind loading, using Ibrahim time domain and stochastic subspace identification methods. On this basis, the variation of aerodynamic mass and damping with wind direction, wind speed, pretension is researched, and reasons for the difference between previous research achievements are analyzed by comparison. The results show that: the aerodynamic mass changes with the wind direction and gets maximum under oblique wind direction, increases with the wind speed increment, and decreases with the pretension increment; the damping ratio of first order modal increases with the increase of wind speed.