输水管管内探测球的动力学特性研究

发布时间：2018-06-06 00:47

本文选题：漏损探测球 + 绕流　；参考：《浙江大学》2015年硕士论文

【摘要】：管道漏损检测是保障管道系统安全的重要手段。针对检测长距离海底管道输水漏损等新情况,提出了智能探测球技术进行漏损检测。本文对探测球在管道中的运动进行了模型实验和数值模拟研究,研究内容着重于探测球设计参数及管道系统工况对其运动的影响,为实际工程应用提供理论基础。本文首先对有压管中探测球滚动前进的动力学特性进行了理论分析,研究了球体运动速度与各影响因素之间的函数关系,为模型实验和数值模拟提供理论基础。在此基础上,设计了探测球在管中滚动行进的模型实验,探讨了球体在有压管道中滚动前进速度受管道内来流速度、球体与管道直径比、球体比重、管道倾斜坡度的影响,测得24颗不同比重、不同直径的塑料球体在不同倾斜程度管道中运动的速度,并得到了球体爬坡所需的最小来流速度。实验结果表明球体速度与来流速度及直径比成正比,与比重及坡度成反比。最后应用三维计算流体力学(CFD)理论建立了球体运动的RNG κ-εs数值模型,并对探测球的运动特性进行了三维数值模拟,得到探测球周围流体的速度和压力分布规律,分析了来流流速的改变对球体绕流流态和阻力系数的影响,给出了与直径比和雷诺数有关的阻力系数方程。本文的主要创新点是通过实验和数值模拟研究了探测球在流体推动下管内滚动前进时的动力学特性,为优化探测球的设计参数及探测球定位提供技术支持。
[Abstract]:Pipeline leakage detection is an important means to ensure the safety of pipeline system. In view of the new situation of detecting water leakage in long distance submarine pipeline, an intelligent ball detection technique is put forward for leak detection. In this paper, the model experiment and numerical simulation of the motion of the detecting sphere in the pipeline are carried out. The research focuses on the influence of the design parameters of the detecting sphere and the operating conditions of the pipeline system on its motion. In this paper, the dynamic characteristics of detecting the ball rolling forward in a pressurized tube are analyzed theoretically, and the functional relationship between the velocity of the ball and the influencing factors is studied. It provides theoretical basis for model experiment and numerical simulation. On the basis of this, the model experiment of detecting the ball rolling through the pipe is designed, and the influence of the rolling forward velocity of the ball in the pressure pipeline on the flow velocity in the pipeline, the ratio of the diameter of the sphere to the pipe, the specific gravity of the sphere, and the slope of the pipe are discussed. The velocities of 24 plastic spheres with different specific gravity and different diameters in the pipe with different inclination degree were measured, and the minimum flow velocity needed for the ball climbing was obtained. The experimental results show that the velocity of the sphere is directly proportional to the velocity and diameter ratio of the incoming flow, and inversely proportional to the specific gravity and slope. Finally, the RNG 魏-蔚 s numerical model of sphere motion is established by using the theory of three-dimensional computational fluid dynamics (CFDs). The velocity and pressure distribution of the fluid around the sphere is obtained by three-dimensional numerical simulation of the motion characteristics of the detecting sphere. The influence of flow velocity on the flow state and drag coefficient around a sphere is analyzed, and the equation of drag coefficient is given, which is related to the diameter ratio and Reynolds number. The main innovation of this paper is to study the dynamic characteristics of the probe ball when it is rolling forward in the tube driven by fluid through experiments and numerical simulation, which provides technical support for optimizing the design parameters of the probe ball and the location of the probe ball.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U178;P756.2

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