天然气管道投产置换混气段长度的研究

Study on Length of Gas Mixture Segment for Commissioning Replacement of Long-distance Gas Pipeline

依据扩散基本理论和对流扩散方程建立的对流——扩散模型,推导出混气长度计算公式。利用FLUENT模拟软件对天然气管道的氮气置换过程进行模拟,得出各主要影响因素对混气长度影响的一般规律。根据气体紊流扩散原理,构建天然气管道投产置换实验平台,对不同流速下管道内气体的扩散过程进行实验研究。通过模拟结果与实验结论的对比,获得天然气管道置换过程混气长度的变化规律,为天然气管道投产置换确定合理参数提供了理论依据。

Established is the convection diffusion model on the basis of basic diffusion theory and convection diffusion equation and derived is the theoretic formula for calculating the length of the gas mixture segment.Adopted is the simulation software FLUENT to simulate the process of nitrogen replacement in gas pipeline and found is the universal law of the main influencing factors' effect on the length of the gas mixture segment.Established is an experimental platform for commissioning replacement of gas pipeline according to the gas turbulent diffusion principle and experimental study is conducted on the gas diffusion process in the pipeline under different flow velocity conditions.Compared are the simulation results with the experimental ones and obtained is the change law of the gas mixture segment length in gas pipeline replacement process,which can provide theoretical basis for reasonably determining relative parameters in gas pipeline commissioning replacement process.