湿模态管道振动特性研究

Study on Vibration Characteristics of Wet-Mode Pipeline

本文采用数值模拟法计算不同长度、不同固定方式的管道在空气中和在水中的振动频率和振型。采用锤击试验法验证了在数值模拟方法下得到的管道自由态和单端固支状态下的固有频率值。对比模拟分析与实验结果,得出各阶共振频率差都小于6%,在误差在允许范围内,验证了理论分析结果可靠。采用Block Lanczos模态提取方法得到了传热管的前12阶模态振型图和固有频率。最后以L=1000mm的模型为例,分析了约束、管外流体阻尼对管道振动特性的影响。结果表明:约束状态、管外流体阻尼对管道的固有频率及振幅都有较大的影响,管道的频率大小与其自身长度有关,自身长度越短,管道的振动频率越高。

Numerical simulation method is used to calculate the vibration frequency and mode of pipe in air and water.The natural frequency values of the pipe free state and the single-end solid state are verified by hammer test.Comparing the results of simulation and experiment,it is concluded that the difference of resonance frequency of each order is less than 6%.Block Lanczos modal extraction method is used to obtain the first 12 modal modal diagram and natural frequency of the heat transfer pipe.Finally,taking the model of L=1000mm as an example,the influence of constraint and external fluid damping on vibration characteristics of pipeline is analyzed.The results show that the constraint state and the external fluid damping have a great influence on the natural frequency and amplitude of the pipe.The frequency of the pipe is related to its own length.The shorter its length,the higher the vibration frequency of the pipe.