风机叶片气固耦合特性研究Research on Air-structure Coupling Characteristic of Fan Blade
李林凌,黄其柏
LI Lin-ling,HUANG Qi-bai (Huazhong University of Science and Technology
摘要(Abstract)：
针对风机叶片外形复杂的特点,假设结构浸入无限大的气流场中,可运用虚质量法。对风机叶片和周围空气选用相同的三维等参单元进行离散,应用Galerkin法计算气体内任意点压强,气体通过质量矩阵直接与结构耦合,推导出风机叶片与周围气体耦合微分方程模型。运用威尔逊-θ法求解耦合微分方程,得到考虑周围空气作用时风机叶片的模态,并用试验测试风机叶片在空气中的模态,比较两种方法得到的模态。利用模态分析理论对风机叶片颤振、噪声辐射特点等进行分析,研究风机叶片与周围媒质耦合对叶片颤振、声辐射的影响。
In the fan structure,its blades have the very complex shape.The virtual mass method is used to research on the fan blade characteristic.It is assumed that the fan blades immerse the infinite gas field.The iso-parametric element is used to discretize the fan blades and its the surrounding air.The random intensity of pressure of the surrounding air is solved by the Galerkin method.The gas coupled with the structure directly by the gas mass matrix.The coupling differential equation model of the fan blades and its surrounding air is made.The Wilson-θ method with well stability is used to solve the differential equation model.The fan blade mode with the surrounding air is obtained.The same fan blade mode is tested too.The calculating model and testing model are compared.The result is reasonable.The model method is used to calculate and analyze the fan blade dynamic characterize in the air in order to study the air-structure coupling affecting on the fan blade chattering and sound radiation characterize.
关键词(KeyWords)：
风机叶片;虚质量法;气固耦合;模态
fan blade;virtual mass method;air-structure coupling;blade mode
基金项目(Foundation):
作者(Author):
李林凌,黄其柏
LI Lin-ling,HUANG Qi-bai (Huazhong University of Science and Technology
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