LNG气化站气相管道天然气泄漏扩散的数值模拟与分析

发布时间：2019-01-24 21:44

【摘要】：近年来，随着国际天然气市场的快速发展，我国天然气市场发展已经进入黄金期。其中液化天然气（LNG）行业是天然气领域中的一个重要组成部分。近几年，随着国内LNG气化站的广泛推广与应用，对其建设与安全运行管理的要求越来越高。本文对LNG气化站内气相管道天然气泄漏扩散过程进行了数值模拟分析，得到一些有意义的结论。本课题利用气体射流理论、传热传质学等理论分析结合数值模拟研究方法，在已有研究成果基础上以实际工程为背景提出具体研究方案。利用Fluent、Tecplot软件进行模型建立及模拟结果后处理。结合浓度场和速度场分析了泄漏孔径、风速大小、泄漏方向、障碍物分布、泄漏源位置五种因素对天然气泄漏扩散的影响。通过模拟结果分析，得出以下结论：泄漏孔径越大，同气体浓度边界范围分布越广，且喷射速度随距离增加而减小的趋势越平缓；随着风速的增加，天然气的喷射距离呈现先增大后减小的趋势；由于是轻质气体，横向泄漏时比竖直泄漏所形成的近地面危险区域较大；障碍物数量越多对气体扩散的局限作用越强，泄漏孔距离障碍物越远，障碍物迎风面对天然气的阻挡作用越明显；泄漏位置不同时，由于周边环境不同，，气体扩散范围不同。这些结论不仅可以指导厂站的安全性工作，而且对今后该方面课题更深程度的研究提供了有价值的理论支持。
[Abstract]:In recent years, with the rapid development of international natural gas market, China's natural gas market has entered a golden period. Liquefied natural gas (LNG) industry is an important part of natural gas field. In recent years, with the wide spread and application of LNG gasification station in China, the requirements for its construction and safe operation management are becoming higher and higher. In this paper, the leakage and diffusion process of natural gas in LNG gasification station is numerically simulated and some meaningful conclusions are obtained. Based on the theoretical analysis of gas jet theory, heat and mass transfer theory and numerical simulation research method, this paper puts forward a specific research scheme based on the existing research results in the background of actual engineering. Fluent,Tecplot software is used to build the model and post-process the simulation results. Combined with concentration field and velocity field, the effects of five factors, such as leakage aperture, wind speed, leakage direction, obstacle distribution and location of leakage source, on the leakage diffusion of natural gas are analyzed. Through the analysis of the simulation results, the following conclusions are drawn: the larger the leak aperture, the wider the distribution of the boundary range of the same gas concentration, and the more gentle the trend of the jet velocity decreasing with the increase of the distance; With the increase of wind speed, the injection distance of natural gas increases first and then decreases. The more the number of obstacles is, the stronger the limitation of gas diffusion is, the farther the leakage hole is from the barrier, the more obvious the barrier is to the natural gas in the wind, and the different leakage location is, because of the different surrounding environment, the gas diffusion range is different. These conclusions can not only guide the safety work of the plant and station, but also provide valuable theoretical support for the further study of this subject in the future.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TE88;TU996.9

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