基于离散方法的气体扩散数学模型.PDF

投产与运行 2014 年9 月　第33 卷第9 期 1000-8241 2014 09-0988-04 文章编号： （ ） 基于离散方法的气体扩散数学模型 庞坤　段耀勇　李秀林 中国人民武装警察部队学院基础部数学教研室，河北廊坊 065000 摘要：在储罐气体泄漏扩散过程中，泄漏强度随时间变化，但常用的高斯扩散模型假设泄漏源恒定， 因而使扩散计算结果与实际情况存在偏差。瞬时泄漏是瞬间释放气团，可以认为连续泄漏是多个瞬 间泄漏释放气团的叠加，而每个瞬间释放气团的泄漏强度不同，基于此，对连续泄漏强度和连续释放 气团进行离散，改进高斯连续扩散模型，得到了理论上更加合理的各距离和时间段地面浓度随时间 的分布函数，并以乙炔瓶泄漏实例进行验证。结果表明：改进模型可以模拟泄漏强度变化大、泄漏 时间长以及任意时刻的泄漏和扩散情况。（图2，表2，参10 ） 关键词：气体储罐；扩散；数学模型；模型改进；离散方法 中图分类号：TE88　　　　　 文献标识码：A　 　　　doi ：10.6047/j .issn.1000-824 1.2014.09.015 A mathematical model of gas diffusion based on discrete method PANG Kun, DUAN Yaoyong, LI Xiulin Staff Room of Mathematics, Dept of Basic Theories, Chinese People’s Armed Police Forces Academy, Langfang, Hebei, 065000 Abstract: In the diffusion of gas leaked from storage tank, the leakage intensity changes over time. However, the commonly used Gaussian diffusion model assumes that the leakage source is constant, which leads to a deviation between calculation result and actual situation. Instantaneous leakage releases air mass instantaneously, and continuous leakage can be regarded as a superposition of air mass in several instantaneous leakages. The leakage intensity of air mass in every instantaneous leakage is different. On this basis, the continuous leakage intensity and free air mass are discretized to improve the Gaussian continuous diffusion model. Therefore, a more theoretically-reasonable distribution function of ground gas concentration with time at different distances and intervals is obtained. This function is verified by ethyne tank leakage. The results show that the improved model can simulate gas leakage and diffusi