摘要
有压流体受到扰动时压力和密度等参数会产生持续性波动并传播,压力波具有传递能量和携带信息的属性,可用于管道泄漏检测。通过搭建压力波管路试验系统,利用机械冲击激发压力波并分析其首波幅值特性,探讨了管路泄漏时压力波传播及衰减的规律。利用FLUENT软件建立了管道系统的二维模型,就压力波衰减比值开展了模拟与试验结果的验证,并将该模型用于长管道的压力波传播特性分析。研究表明:机械冲击产生的最大压力波首波幅值约为178.0 kPa,试验中采用的压力波幅值约为95.2 kPa。压力波在经过泄漏口后幅值大幅衰减形成次压力波,同时发生反射,导致膨胀波的叠加位置发生改变,解释了泄漏时的压力波传播现象。当泄漏口的尺寸由1 mm增大至5 mm时,次压力波会减弱而反射的压力波增强;管长相对压力波半波长的大小影响压力波的叠加状态,利用泄漏后对应膨胀波的相位差可测算出泄漏口位置。
The pressure and density of pressurized fluid can continuously fluctuate and propagate when it is disturbed. The pressure wave has the properties of transmitting energy and carrying information, and then can be used for pipeline leakage detection. Through building up a pressure wave-based pipeline experiment system, the pressure wave is generated with mechanical shock and the amplitude characteristics of its head wave is analyzed, and then the propagation and attenuation law of the pressure wave during the leakage of pipeline is discussed herein. Moreover, a 2-D simulation model for the pipeline system is established with the software -- FLUENT for verifying the simulation and experiment results of the attenuation ratio of the pressure wave, while the model is applied to the analysis on the propagation characteristics of the pressure wave in long pipeline as well. The study shows that the maximum amplitude of the head wave of the pressure wave generated by mechanical shock is about 178.0 kPa, while the amplitude of pressure wave adopted in the experiment is about 95.2 kPa. The amplitude of pressure wave greatly attenuates after passing through leaked port and then forms a secondary pressure wave along with the simultaneous occurrence of a reflection wave, which results in the change of the superposition position of the expansion wave and explains the propagation phenomenon of the pressure wave during leakage. The secondary pressure wave is to be weakened, but the reflection wave is to be increased when the size of the leaked port is increased from 1 mm to 5 mm, while the size of the pipeline relative to the half-wavelength of pressure wave affects the superposition state of the pressure wave, thus the location of the leaked port can be calculated with the phase difference of the corresponding expansion wave occurred after leakage.
作者
郭希健
曹峥
宣炳蔚
邓建强
GUO Xijian;CAO Zheng;XUAN Bingwei;DENG Jianqiang(School of Chemical Engineering and Technology,Xi’an Jiaotong University,Xi’an 710049,Shaanxi,China;Shaanxi Key Laboratory of Energy Chemical Process Intensification,Xi’an 710049,Shaanxi,China)
出处
《水利水电技术（中英文）》
北大核心
2021年第6期94-104,共11页
Water Resources and Hydropower Engineering
基金
国家自然科学基金项目(21978227)
中央高校基本科研业务费(xjh012019022)。
关键词
管道泄漏检测
压力波传播
压力波衰减
流体动力学
计算流体动力学
水力特性
数值模拟
pipeline leakage detection
pressure wave propagation
pressure wave attenuation
hydrodynamics
computational fluid dynamics(CFD)
hydraulic characteristics
numerical simulation
