风作用下街区内重气扩散模拟方法研究  

Research on simulation method of heavy gas dispersion on block-scale under wind

作　　者：赵东洋[1] 崔铁军[2,3] 

机构地区：[1]辽宁工程技术大学环境科学与工程学院,辽宁阜新123000 [2]辽宁工程技术大学安全科学与工程学院,辽宁阜新123000 [3]大连交通大学辽宁省隧道与地下结构工程技术研究中心,辽宁大连116028

出　　处：《中国安全生产科学技术》2014年第6期72-77,共6页Journal of Safety Science and Technology

基　　金：辽宁省教育厅科技项目(L2012121)

摘　　要：为模拟在风作用下重气泄漏在街区内近地扩散,基于细胞自动机-气团模型对其进行了模拟。宏观层面上将气体视为多个气团的集合,利用细胞自动机构建了重气在风作用下的运动模型。气团特征可表示为模型Qi(珗V0i,xi,yi),影响半径D是基于高斯模型确定的,并用以区分浓度梯度扩散Sd和自由扩散Sf,确定了风在街区内的强度分布,并设定边界接触条件。假设了模拟的市内环境,使用该模型在风速u=0.75m/s状态下模拟氨气扩散,并研究了不同时刻风进入街区对扩散的影响。结果表明:该模型能模拟在给定的稳定风场下的重气连续扩散及其特征;能模拟风在不同时刻通过整个街区对扩散的变化影响及其特征,从而为设计逃生路线和灾害控制提供依据。In order to simulate the leakage of heavy gas in urban area and dispersion on block-scale under wind,the cellular automata-air mass model was applied. The macroscopic gas dispersion was equivalent as the set of multi air mass dispersion; the motion model of heavy gas dispersion under wind was constructed by CA-air mass. The characteristics of air mass were expressed as Qi（ →V0i,xi,yi）. With the Gaussian model,the influence radius D was determined to distinguish between the Sdand Sf. The distribution of wind intensity in the block was determined,and the contact boundary conditions were set. By the simulation of urban environment,the ammonia diffusion was simulated under wind speed u = 0. 75m /s. The result showed that the air mass dispersion was in line with the actual situation. The number of air mass can represent the heavy gas concentration,and the effect on dispersion when the wind goes cross the block in different time can be obtained. The succession diffusion of heavy gas and its characteristics can be simulated under the given stable wind field,so as to facilitate escape and disaster control.

关 键 词：气团模型 市内街区 重气泄漏 有风作用 扩散模拟 

分 类 号：X924.2[环境科学与工程—安全科学]