火电厂给水再循环管道振动分析与控制

Vibration analysis and control on water feeding & recycling pipe system of thermal power plant

针对某火电厂给水再循环管道振动的原因和集中位置进行分析并提出相应的控制方案。首先建立再循环管道和水流的实体模型、支吊架简化模型并进行装配,然后导入至ANSYS中进行CFX流体分析,得到水流作用于管道内壁的冲击压力并导入至结构力学模块进行二次分析,再将分析数据传递至模态分析模块进行运算,得到流固耦合作用下管系前50阶的固有频率和前6阶振型,最后结合实验测试结果分析再循环管道振动的原因和振型最大点位置分布规律,并提出相应的支吊架调整干预方案,调整后管系各阶固有频率有所上升,管系振动明显好转,表明所提控制方案可行、有效。该文工作对于火电厂给水再循环管道振动的监测和控制有参考价值。

The vibration cause and control method of the water feeding ＆ recycling pipe system in a thermal power plant were analyzed. The 3D models of the pipe, the water, and the simplified cradle were firstly set up and assembled, and then imported into ANSYS CFX for fluid analysis. The pulse pressure was transferred to the inner surface of the pipe to perform a structure calculation, based on which the modal analysis was taken to obtain the former 50-order natural frequencies and the former 6-order vibration modes. Finally, according to the experiment test and the theoretical analysis, the vibration cause and the distribution principles of the vibration amplitude position were investigated, and the cradle adjustment schemes for the vibration control were proposed as well. It shows that the natural frequencies of the pipe system are increased after the cradle adjustment operation, while the vibration amplitudes are significantly decreased. The presented work in this paper offers a reference for the vibration monitoring and control of the water feeding ＆ recycling pipe system in thermal power plants.