摘要
输水管道系统中经常出现的水锤现象导致管道出现变形甚至爆管等故障,现有的水锤数值仿真模拟大多是基于传统的水锤理论,忽略了水锤的动态摩阻衰减效应和管道的布拉格共振效应.因此,全面分析水锤的频域响应特点和管道的布拉格共振效应有助于解决在供水管道中出现的水锤精准数值仿真问题,为管道系统的阻塞检测和泄漏检测等各种问题提供理论基础.本文构建了两种模型,即特征线法与Vardy-Brown动态摩阻耦合的时域求解模型和传递矩阵法与Vardy-Brown动态摩阻耦合的频域求解模型.为了验证模型的精确性,搭建了水锤试验台.为了验证管道的布拉格共振效应,使用频域求解模型分析摩阻和测点位置对频率响应函数(FRF)和无量纲波幅的影响.结果表明,不同初始压力和瞬变流量不会影响FRF谐振峰(谐振峰是指在频率响应曲线上FRF达到最大值的点)在钢管中的分布情况,此外FRF谐振峰频率等于奇数倍的理论频率.时域求解模型决定系数(R^(2))为0.9823,频域求解模型决定系数(R^(2))为0.9249,说明所构建的两种模型的精确性.在动态摩阻效应的作用下,各个理论频率周期对应的谐振峰值均有不同程度的衰减.稳态摩阻和动态摩阻对波幅图没有影响,使用波幅图可以解释不同摩阻和不同位置对FRF谐振峰的影响作用.验证了管道布拉格共振效应,当测点靠近谐振峰共振模式的驻点时,其峰值为最大,其谐振峰峰值基本无衰减;当测点靠近谐振峰共振模式的节点时,其峰值为最小,其谐振峰值衰减最明显.
The water hammer phenomenon is frequently observed in water conveyance pipeline systems,and it leads to pipeline deformation and even pipe bursting.Existing numerical simulations of the water hammer are often based on traditional water hammer theories,neglecting the unsteady frictional attenuation and Bragg resonance effects in pipelines.Therefore,a comprehensive analysis of the frequency-domain response characteristics of the water hammer and the Bragg resonance effect in pipelines can help address the issue of accurate numerical simulation of the water hammer in water supply pipelines,providing a theoretical basis for various pipeline system problems,such as blockage and leakage detection.In this study,two models,i.e.,a time-domain solution model coupling the method of characteristics and the Vardy-Brown unsteady friction,and a frequency-domain solution model coupling the transfer matrix method and the Vardy-Brown unsteady friction,were constructed.To verify the accuracy of the models,a water hammer experimental platform was established.To validate the Bragg resonance effect in pipelines,the frequency-domain solution model was used to analyze the influence of friction and measurement point location on the frequency response function(FRF)and the dimensionless wave amplitude.Results showed that different initial pressures and transient flow rates did not affect the distribution of the FRF resonance peaks(the resonance peaks refer to the points where the FRF reaches its maximum value on the frequency response curve)in steel pipes.In addition,the FRF resonance peak frequency was equal to the odd-multiplex of the theoretical frequency.The coefficient of determination(R^(2))for the time-domain solution model was 0.9823,and that for the frequency-domain solution model was 0.9249,indicating the accuracy of the two models constructed in this study.Under the influence of unsteady friction,the resonance peak values corresponding to each theoretical frequency period exhibited varying degrees of attenuation.Steady-state friction and unsteady friction did not affect the wave amplitude diagram,which could be used to explain the influence of different friction types and different locations on the FRF resonance peaks.This study validated the Bragg resonance effect in pipelines.When the measurement point was close to the antinode of the resonance mode of the resonance peak,the peak value was the highest,and the resonance peak value showed nearly no attenuation.When the measurement point was close to the node of the resonance mode of the resonance peak,the peak value was the lowest,and the attenuation of the resonance peak value was more pronounced.
作者
周领
张俸溢
潘天文
李赟杰
侯庆志
Zhou Ling;Zhang Fengyi;Pan Tianwen;Li Yunjie;Hou Qingzhi(College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China;Yangtze Institute for Conservation and Development,Hohai University,Nanjing 210098,China;State Key Laboratory of Water Resources Engineering and Management,CISPDR Corporation,Wuhan 430010,China;School of Civil Engineering,Tianjin University,Tianjin 300350,China)
出处
《天津大学学报(自然科学与工程技术版)》
北大核心
2025年第10期1009-1020,共12页
Journal of Tianjin University:Science and Technology
基金
青海省2025年中央引导地方科技发展资金专项资助项目(2025ZY040)
宁波市重大专项“科创甬江2035”关键技术资助项目(2024Z285)
中国科技交流中心资助项目(4-15)
国家自然科学基金资助项目(52209084,51679066).
关键词
时域求解模型
频域求解模型
动态摩阻
频率响应函数
波幅图
time-domain solution model
frequency-domain solution model
unsteady friction
frequency response function(FRF)
wave amplitude diagram
