轴流式叶片的流固耦合振动特性分析

Analysis of Fluid-Solid Coupling Dynamic Characteristics for the Axial Flow Blades

采用流固耦合技术,求解流体与固体的耦合方程,对轴流式叶片进行了振动特性分析,分别计算了叶片在空气中和水中的固有频率;并比较了轴流式叶片在空气中与水中固有频率的变化,分析了叶片在水中的振型。结果表明,叶片在水中的各阶固有频率较其在空气中均有所降低,且其降低程度具有非线性的特点。通过对轴流式叶片在水中八阶模态图的分析,表明了轴流式叶片外部靠近出水边的地方较为敏感。

The fluid-solid coupling tech is adopted to seek for the fluid and solid coupling equation. The dynamic characteristics for the axial flow blades is analysed. The natural frequency of the blades was calculated in water and in air respectively. The variations in natural frequency of the axial flow blades in air and in water are compared;and the vibration mode of the blades is analysed. The results indicate that each order natural frequency of the blades has a slighter drop in water than in air,whose dropping degree is characterized by the non-linearity. The analysis of 8-order mode of the axial-flow blades in water shows that the place close to outlet of the outside of the axial flow blades is much more sensitive.