亚声速叶片与跨声速叶片的气动阻尼比较

Comparison on aerodynamic damping between subsonic blade and transonic blade

关键词:  气动阻尼  跨声速叶片  亚声速叶片  模态  振幅  压缩波

Key words:  Aerodynamic damping  Transonic blade  Subsonic blade  Mode  Vibration amplitude  Compression wave

摘要:

为了研究叶轮机中叶片与流场流固耦合作用情况下的气动阻尼,分别以亚声速和跨声速转子叶片为例计算气动阻尼。根据对非定常气动力的分析,提出了一种与结构等效粘滞阻尼比对应的模态气动等效粘滞阻尼比的定义。采用弱耦合分域求解的算法,在线性范围内,计算并比较了跨声速叶片和亚声速叶片模态和振幅对模态气动阻尼比的影响,根据分布气动阻尼比研究压缩波对模态气动阻尼比的影响。研究结果表明这两类叶片的气动阻尼特性基本一致,所提参数对两类叶片的气动阻尼的影响基本相同。

Abstract:

In order to study the aerodynamic damping from fluid-structure interaction in turbo-machinery,the aerodynamic damping is computed for subsonic blade and transonic blade.The method introduced defines the aerodynamic damping as viscous damping in structure that is viscous damping ratios multiplied by velocity.The low level coupling is used to solve the problem.The paper analyses the effect of different modes and different vibration amplitudes under linearity between the subsonic blade and the transonic blade and the effect of compression wave in subsonic and transonic vane cascades.The similar results of aerodynamic damping can be obtained between the subsonic blade and the transonic blade and the effect of the listed parameters is similar.