There iss strong vibration in the draft tube of a Francis turbine or axial flow fixedbladepropeller hydraulic turbine when the turbine is running on part loading.
混流和轴流定浆式水轮机在部分负荷下运行时，尾水管中常出现较为强烈的振动。
2
A new method for analyzing twin-bladefixed-pitch propeller was proposed based on the theory of corrected blade foil and aerodynamic formula of 3-d wing.