天然气管道清管器跟踪定位模拟与实践

Simulation and practice of pig tracking and locating in natural gas pipeline

在天然气管道清管过程中,需要应用可靠的技术手段对清管器跟踪定位,以便确定清管器到达管道沿线各点的时间,并根据清管器所在位置确定开始执行收球流程切换的时间。基于热力学关系和状态方程,将连续性方程、运动方程、能量方程的各系数表示为压力、温度的函数,并采用一阶有限差分格式进行离散,求解方程组得到管道沿线的压力、温度分布,从而实现天然气管道清管器的准确定位。通过华中地区某天然气管道支线的清管定位实践,证明该方法有助于提高天然气管道仿真计算的精度,能够满足工程实际需求。(表1,图5,参10)

In the process of pigging in natural gas pipeline,it is necessary to utilize the precise and reliable technical means for pig tracking and locating in order to determine the time of pig arrival at points along the pipeline and define the time of start-up for pig collection based on pig position.On the basis of thermodynamics and state equation,coefficients in continuity equation,motion equation and energy equation are expressed as functions of pressure and temperature,and discretized in first-order finite difference format.The equation set is solved to obtain the distributions of pressure and temperature,hence realizing the precise location of pig within gas pipeline.From pig locating practice in a natural gas transmission branch in central China,it is proved that the method is helpful to enhance the accuracy in emulation calculation of natural gas pipeline and the actual engineering requirement can be satisfied.