论文部分内容阅读
冬季是北方城市高压燃气管网发生冻堵的多发期,为了解决天然气调压器冻堵问题,对天然气调压器水合物冻堵因素及形成进行定量研究。根据计算流体动力学理论,采用数值模拟方法对天然气流经调压器的压力变化进行数值模拟,进而定性与定量地分析冻堵的形成过程。模拟得到调压器前、后管道以及阀口处的压力分布图、速度分布图和速度矢量图。结果显示,阀口处速度增加,阀口前、后压力变化明显,漩涡位置清晰,这些与实际工程中发生的冻堵情况相符合。天然气在阀口处具有低温、高压、水分滞留、强烈扰动的特点,为水合物的形成提供了条件。结果表明:调压器阀口处是形成冻堵的薄弱部位,冻堵的形成是一个动态过程,同时也是一个加剧过程,一旦发生冻堵而没有采取及时的措施,那么冻堵情况就会越来越严重。
In winter, the high pressure gas pipeline network in the northern city is prone to freezing and blockage. In order to solve the problem of freezing and blocking of the natural gas pressure regulator, the factors and the formation of gas hydrate freezing blockage in natural gas are quantitatively studied. According to computational fluid dynamics theory, the numerical simulation method is used to simulate the pressure change of natural gas flowing through the pressure regulator, and then qualitative and quantitative analysis of the formation of freeze block. The pressure distribution, velocity distribution and velocity vector are obtained by simulation before and after the pipeline and valve. The results show that the speed at the valve port increases, the pressure changes obviously before and after the valve port, and the whirlpool position is clear, which accords with the situation of freezing and blocking in the actual project. Natural gas at the valve port has low temperature, high pressure, water retention, strong perturbation characteristics, provided the conditions for the formation of hydrate. The results show that the pressure valve is formed at the valve port of the weak part of the freeze block, the formation of frozen block is a dynamic process, but also an exacerbated process in the event of freezing block without taking timely measures, then freeze the situation will be more blocking The more serious.