摘要
为了研究温度场作用下超临界流体在多孔介质流动中"可调"性质的变化特性,针对各向同性多孔圆柱体建立了多孔介质中超临界流体的流动与传热耦合传递过程数学模型。在均匀加热和非均匀加热条件下,采用 COMSOL Multiphysics 3.3a 软件对模型方程进行数值求解,研究了超临界 CO_2注入砂床过程中流体"可调性"随局部压力和温度耦合变化的特性。研究表明,非均匀的线性加热条件可以改变近壁区的流动特性,使多孔介质内在近壁处的流体速度沿流动方向趋于平均,在一定程度上加速壁面处滞缓的流体;超临界流体相对密度等性质的分布特性主要受计算区域中温度和流速影响而发生较大变化。施加温度梯度的作用可以成为调控多孔介质中超临界流体"可调性"的手段。
In order to study the “tunable” performances of supercritical fluid flow in porous media with temperature profiles, a mathematical model of supercritical fluid flow in porous media coupling with heat transfer was established for an isotropic porous cylinder. Under the conditions of uniform and non-uniform heating boundaries, COMSOL Multiphysies 3. 3a software was used to solve the equations numerically and simulate “tunable” characteristics of the injection of supercritical CO2 into sand bed with the changing of local pressure and temperature. The computational results showed that the linear non-uniform heating condition could change the flow characteristics of the fluid close to the inner wail of the porous media. The fluid velocity along the flow direction tended to be averaged in the region close to the heating wall. To a certain extent, heating could accelerate the stagnant fluid near the wall. The relative density and other properties of the fluid in the calculation domain were mainly influenced by local temperature and velocity. The results implied that imposing temperature gradient on porous media was an effective way to regulate and control the “tunable” performance of the supercritical fluid in porous media.
出处
《化学反应工程与工艺》
EI
CAS
CSCD
北大核心
2008年第4期289-294,311,共7页
Chemical Reaction Engineering and Technology
基金
国家自然科学基金重点项目(20436040)
国家自然科学基金项目(20876123)
关键词
多孔介质
超临界流体
传热
流动
耦合
可调性
数值模拟
porous media
supercritical fluid
heat transfer
flow
Coupling
tunable performance
numerical simulation
