埋地天然气管道泄漏温度场模拟

The Simulation of Temperature Field of Underground Natural Gas Pipeline Leakage

为了解埋地管道泄漏后附近温度场的分布情况,以便对管道发生小孔泄漏进行泄漏检测,本文对埋地输气管道泄漏前后建立了二维物理模型和数学模型并给出了相应的边界条件。利用计算流体软件Fluent对环境温度、输送压力、泄漏口孔径与泄漏方向四种泄漏工况分别进行了管道泄漏后的数值模拟。结果表明:环境温度、输送压力是决定管道泄漏后土壤温度场分布的决定性因素;泄漏口孔径也会对土壤温度分布造成影响,但影响效果小于环境温度和输送压力的影响;泄漏方向更大程度影响冷影响区的相对位置,而对冷影响区域的大小影响不大。本文最终得到了不同工况下管道泄漏后周围土壤温度场的分布情况,对当前广泛应用的光纤传感器的现场应用有一定的指导意义。

In order to understand the distribution of temperature field in the vicinity of buried pipelines after leakage and to detect the leakage of small holes in pipelines,a two-dimensional physical model and mathematical model were established before and after the leakage of buried gas pipelines,and the corresponding boundary conditions were given.The numerical simulation of pipeline leakage under four leakage conditions,namely,environmental temperature,delivery pressure,aperture of leakage port and direction of leakage,was carried out by using the computational fluid software Fluent.The results show that ambient temperature and conveying pressure are the decisive factors for the distribution of soil temperature field after pipeline leakage;the pore size of the leakage port also affects the soil temperature distribution,but the effect is less than that of the ambient temperature and transport pressure;the direction of leakage has more influence on the relative position of the cold affected area,but has little influence on the size of the cold affected area.In this paper,the distribution of the soil temperature field around the pipe leakage under different working conditions is obtained,which has a certain guiding significance for the field application of fiber optic sensors widely used at present.