中文摘要：

为研究环氧乙烷在不同因素影响下扩散规律及其毒性影响范围，以某厂环氧乙烷储罐泄漏事故为背景，对环氧乙烷泄漏扩散规律进行模拟分析。运用FLUENT软件，模拟环氧乙烷随泄漏速率、自然风速和地面粗糙度变化时的动态扩散变化规律。模拟结果表明：1）泄漏速率越快，毒害范围越大，并且在一定条件下，泄漏速率每增加2．5 kg／s，特别严重毒害范围（灰区）最远距离会在下风向增加60～80 m，比较严重毒害范围（黑区）最远距离会在下风向增加20～40 m；2）自然风速越快，灰区范围会变得越来越小，但黑区的毒害范围会扩散得更大，当风速为8m／s时达到最大值，风速超过8 m／s时，风速的增加反而会使黑区范围变小；3）地面粗糙度越大，对环氧乙烷扩散的阻碍作用越大，黑区范围变小，但地面粗糙度大于4m后，其对扩散作用的影响与4m时近乎一致。研究结果对环氧乙烷储罐泄漏事故的预防，应急疏散和救援具有重要的指导意义。

英文摘要：

In order to research the dispersion rule and toxic influence scope of ethylene oxide （ EO） under different factors, taking the leakage accident of EO tank in a certain factory as background, the dynamic dispersion rules of EO under different leak rate, natural wind speed and surface roughness were simulated and analyzed by using FLU-ENT.The results showed that：1） The quicker the leakage rate, the larger the toxic influence scope.Under certain conditions, when the leakage rate increases per 2.5 kg/s, the maximum distance of scope with very serious poison （ grey area） increases 60 to 80 m, and that of scope with serious poison （ black area） increases 20 to 40 m as well. 2） The faster the natural wind speed, the smaller the scope of grey area, and the larger the poison scope of black area.When the wind speed reaches 8 m/s, the black area is the largest.When the wind speed exceeds 8 m/s, the scope of black area becomes smaller with the increase of wind speed instead.3） The higher the surface roughness, the smaller the scope of black area due to the higher the hindering effect.If surface roughness is larger than 4 m, the hindering effect is close to that of 4 m.The study is significant to prevention, emergency evacuation and rescue for leakage accident of EO tank.