埋地燃气管道泄漏流量及扩散规律的实验研究
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摘要
分析埋地燃气管道泄漏时,泄漏燃气在土壤中以及地下空腔的扩散规律,研究燃气压力、管道埋深、泄漏方向、泄漏点位置等因素对泄漏燃气体积分数的影响。以天然气为实验气体,开展两组实验:1中压燃气泄漏的9种工况实验,表明:土壤中泄漏天然气体积分数随泄漏时间变化符合S型曲线,且在发生泄漏时,管道埋深越深,泄漏燃气在土壤中的扩散范围越大;泄漏口方向对泄漏燃气扩散的方向具有较大影响。2低压燃气泄漏至密闭空腔的7种工况,表明:空腔前无障碍物时,泄漏到空腔内的燃气量较多,但处于爆炸极限范围内的时间较短;有障碍物时,空腔达到爆炸下限的时间延长,但处于爆炸极限范围内的时间更长;空腔内达到爆炸上下限所需时间与泄漏点距空腔中心距离成指数函数关系,距离越近,达到爆炸上下限的时间越短;燃气泄漏流量与泄漏点距空腔中心的距离成二次方函数关系,距离越近,泄漏流量越大。
The diffusion law of gas leakage in the soil and underground cavity is analyzed when gas leaks from buried pipeline. The influence of gas pressure, buried depth of pipeline, leakage direction,leakage point location,and other factors on volume fraction of leaked gas is studied. Experiments are carried out in two groups with natural gas:( 1) There are9 kinds of working conditions of medium pressure gas leakage,which shows that variation of the volume fraction of leaked gas with the leakage time in the soil is in accordance with the S curve,in the case of leakage,the deeper the buried depth,the greater the diffusion scope of gas in the soil; and the leakage direction has a great influence on the gas leakage diffusion direction;( 2) There are 7 kinds of working conditions of low pressure gas leakage into the sealed cavity, which shows that for cavity without obstacle, gas leakage quantity into the cavity is more,but the time in the range of the explosion limit is shorter. When there are obstacles,the time of reaching the lower limit of explosion for cavity is prolonged,but the time in the range of explosion limit is longer; there is an exponential function relationship between the time required to reach upper or lower explosive limit and the cavity center distance from leakage point,the closer the distance,the shorter the time to reach upper or lower explosive limit; there is a quadratic function relationship between the gas leakage flow and the cavity center distance from leakage point,the closer the distance,the larger the leakage flow.
The diffusion law of gas leakage in the soil and underground cavity is analyzed when gas leaks from buried pipeline. The influence of gas pressure, buried depth of pipeline, leakage direction,leakage point location,and other factors on volume fraction of leaked gas is studied. Experiments are carried out in two groups with natural gas:( 1) There are9 kinds of working conditions of medium pressure gas leakage,which shows that variation of the volume fraction of leaked gas with the leakage time in the soil is in accordance with the S curve,in the case of leakage,the deeper the buried depth,the greater the diffusion scope of gas in the soil; and the leakage direction has a great influence on the gas leakage diffusion direction;( 2) There are 7 kinds of working conditions of low pressure gas leakage into the sealed cavity, which shows that for cavity without obstacle, gas leakage quantity into the cavity is more,but the time in the range of the explosion limit is shorter. When there are obstacles,the time of reaching the lower limit of explosion for cavity is prolonged,but the time in the range of explosion limit is longer; there is an exponential function relationship between the time required to reach upper or lower explosive limit and the cavity center distance from leakage point,the closer the distance,the shorter the time to reach upper or lower explosive limit; there is a quadratic function relationship between the gas leakage flow and the cavity center distance from leakage point,the closer the distance,the larger the leakage flow.
引文
[1]韩光洁.埋地燃气管道泄漏量计算及扩散规律研究(硕士学位论文)[D].重庆:重庆大学,2014:2-11.
[2]徐进生.受限空间燃气管网泄漏扩散及爆炸危害特性研究(硕士学位论文)[D].武汉:武汉理工大学,2014:1-10.
[3]谢昱姝,吴宗之,吕良海,等.城市管道天然气在土壤中泄漏扩散实验研究[J].中国安全生产科学技术,2012,8(4):13-17.
[4]程猛猛,吴明,赵玲,等.城市埋地天然气管道泄漏扩散数值模拟[J].石油与天然气化工,2014,43(1):94-97.
[5]唐保金,田贯三,张增刚,等.埋地燃气管道泄漏扩散模型[J].煤气与热力,2009,29(5):A01-A05.
[6]OKAMOTO H,GOMI Y.Empirical research on diffusion behavior of leaked gas in the ground[J].Journal of Loss Prevention in the Process Industries,2011,24(5):531-540.
[7]WAKOH H,HIRANO T.Diffusion of leaked flammable gas in soil[J].Journal of Loss Prevention in the Process Industries,2001,4(4):260-264.
[2]徐进生.受限空间燃气管网泄漏扩散及爆炸危害特性研究(硕士学位论文)[D].武汉:武汉理工大学,2014:1-10.
[3]谢昱姝,吴宗之,吕良海,等.城市管道天然气在土壤中泄漏扩散实验研究[J].中国安全生产科学技术,2012,8(4):13-17.
[4]程猛猛,吴明,赵玲,等.城市埋地天然气管道泄漏扩散数值模拟[J].石油与天然气化工,2014,43(1):94-97.
[5]唐保金,田贯三,张增刚,等.埋地燃气管道泄漏扩散模型[J].煤气与热力,2009,29(5):A01-A05.
[6]OKAMOTO H,GOMI Y.Empirical research on diffusion behavior of leaked gas in the ground[J].Journal of Loss Prevention in the Process Industries,2011,24(5):531-540.
[7]WAKOH H,HIRANO T.Diffusion of leaked flammable gas in soil[J].Journal of Loss Prevention in the Process Industries,2001,4(4):260-264.