基于流体动力学，应用动量定理研究汽轮机直叶片、短扭叶片、长扭叶片以及汽轮机调节级由于间隙引起的气流激振力问题，综合考虑了叶片的各项设计参数并应用理论分析方法导出普遍适用的计算公式，解决了Alford公式中需人为选取效率系数的困难。数值实验的结果表明，所导出的计算公式是可靠的。

Based on the hydro-dynamics, the computing formulas for air-exciting-vibration force are derived for straight blade, short twist blade, long twist blade and the control stage of steam turbine in uniform air-flow field. Using the presented formulas, the air-exciting-vibration force can be directly calculated based on the design parameters and air-flow parameters of steam turbine. The numerical tests show that the presented formulas are correct and reliable.