多孔介质中强间断条件下多组分物质渗流模拟  

Simulation of multicomponent material seepage in porous media under strong discontinuous conditions

作　　者：张鑫 曹渊[2] 王铁良[2] 何增[2] 郝有志 卢德唐[1] ZHANG Xin;CAO Yuan;WANG TieLiang;HE Zeng;HAO YouZhi;LU DeTang(Department of Modern Mechanics,University of Science and Technology of China,Hefei 230027,China;Northwest Institute of Nuclear Technology,Xi'an 710024,China)

机构地区：[1]中国科学技术大学工程科学学院,合肥230027 [2]西北核技术研究所,西安710024

出　　处：《中国科学：物理学、力学、天文学》2022年第4期96-109,共14页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家重大科技专项(编号:2017ZX05009005)资助项目。

摘　　要：多孔介质强间断情况表现为地层爆炸腔体与周围介质间存在极高的温度和压力梯度,且因爆炸产物的参与形成多相多组分的渗流过程.针对该情形,建立了多孔介质中多相多组分物质非等温渗流数值模型.根据对流传导及地层渗流速度特征对压力和温度进行了解耦;对能量方程采用显式,渗流方程采用全隐式计算.通过对比等温和非等温两种渗流环境计算结果,认为随着时间推移,非等温地层压力呈先上升后下降特点,且位置越靠近空腔,压力上升越快.在温度梯度影响下,地层压力曲线呈波形,达到平衡需要较长时间.而在等温渗流情况下,压力曲线表现平滑,达到平衡较快.此外,该数值模型能够预测各组分气体在地层扩散过程,对地层污染物扩散、垃圾填埋、地层爆破有害气体扩散等有一定指导意义.The strong discontinuity of porous media is manifested in the presence of extremely high temperature and pressure gradients between the explosive cavity of a formation and the surrounding media after an underground explosion.Because of the participation of explosive products, a multiphase and multicomponent seepage process is developed.Considering this situation, a numerical model of nonisothermal seepage flow for multiphase and multicomponent materials in porous media is established. In the numerical model, pressure and temperature are decoupled according to the velocity sensitive characteristics of heat convection while formation seepage has low velocity. The energy equation is calculated using an explicit method, while the seepage equation is calculated with a fully implicit method. Comparing the calculation results of isothermal and nonisothermal seepage environments, it is concluded that with the passage of time,the formation pressure in a nonisothermal environment first rises and then falls, and the closer the position is to the cavity, the faster the pressure rises. Under the influence of a temperature gradient, the formation pressure curve presents a wave shape, taking fifty-two hours to reach equilibrium;while in the case of isothermal seepage, the formation pressure curve is smoother and takes less time(forty-five hours) to reach equilibrium. Additionally, the numerical model can predict the diffusion process of each component gas in the formation. This has a guiding significance for pollution control and environmental remediation, such as diffusing ground pollutants, landfills, and harmful gases from ground blasting.

关 键 词：多孔介质 多相 多组分 温度梯度 压力梯度 气液运输 

分 类 号：O357.3[理学—流体力学]