蒸汽动力装置回汽制动工况下倒车级动叶安全性分析

Bending stress of moving blade of the astern turbines in back-steam braking conditions for steam-powered ships

针对蒸汽动力船舶回汽制动工况下倒车汽轮机叶片的运行安全性问题,通过回汽制动工况下倒车汽轮机的变工况工作过程分析,建立回汽制动工况下倒车级动叶的弯曲应力模型,并基于Matlab-Simulink环境,建立倒车级动叶的弯曲应力的仿真模型。仿真结果表明,回汽制动工况下,采用理想制动策略时倒车级第二级动叶的弯曲应力会超过安全许用值,导致倒车汽轮机的损坏,影响蒸汽动力装置的安全运行,因此需对倒车汽轮机进汽阀开启的时机及幅度进行限制。

For the defect of operational reliability safety in the back-steam braking condition in the moving blade of astern turbines of steam-powered ships. The working process of the variable condition of the astern turbines in the backsteam braking condition was analyzed, and bending stress of the moving blade of astern turbines in the back-steam braking condition was created. Also, the simulation models were created based on the Matlab-Simulink. It was indicated in the simulation results that bending stress of the second moving blade of astern turbines may outstrip the safety allowable value, and damage the astern turbines. Then the safety operations of steam powered plants were affected. So, it is necessary to restrict the open opportunity and range.