空气罐控制管道水击实验研究
An Air Cylinder Used for Surge Control Test
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摘要: 在实验室的简单管路水力系统中, 加设一种气囊式空气罐, 进行简单管路的水击实验, 可以有效地控制水击危害, 并模拟出生产管道的水击动态特性。这种空气罐具有气密性、可更换节流孔口、计算机能够模拟罐的容积的结构特点, 用以达到控制管路系统中因阀门瞬时关闭产生的水击增压速率, 并防止液柱分离。在瞬变分析忽略阀门和罐间摩阻、三通连接的局部摩阻﹑罐和管路间的摩阻、液流惯性和罐内液面变化的前提下, 建立了阀门、空气罐的复合边界数学模型, 列出了计算流程框图, 编制了含有空气罐及阀门复合边界条件的水击模型程序, 绘制了设有空气罐和未设空气罐时三种不同孔口直径的水击压力变化曲线, 并把实测数据和理论计算结果比较, 证明该空气罐设计简单, 使用方便,起到了控制水击的目的。Abstract: In the simple laboratary hydraulic piping system, if an air cylinder like a baloon is added for simple pipleine surge control experiment, surge harm can be prevented effectively. In addition, surge dynamic characteristics of the pipeline in operation can be simulated. This kind of air cylinder has the advantages of being airproof and the restricting runner is replacable, computers can be used to simulate the structural characteristics of the containers so as to control surge pressure boost rate in the pipeline caused by instant shutdown and avoid liquid colume seperation.Based on the trensiency analysis, friction resistance between the valve and cylinder. partial friction resistance at the connection of tees, friction tesistance between cylinder and pipe wall, the inertia of liquid colume and the liquid surface change, a mathematical complex battery limit module has been worked out for valves and air cylinders; a calculation process block diagram, a surge module program consisting of the complex boundary condition of air cylinders and valves, surge pressure change curve of three diffrent orifice—runner diameters with and without air cylinders.Measured data have been compared with calculated result. Which proved that the said air cylinder is simple to design and easy to operate, therefore being able to maintain surge control.