溶剂驱油中的扩散现象研究

The Study of Diffusion Phenomenon in Solvent Displacement

本文通过求一对流-扩散方程的半解析解,分析了扩散系数大小及影响扩散系数的参数对计算出的浓度分布的影响;通过将该半解析解与忽略扩散的数值解进行对比分析,讨论了数值弥散代替物理扩散的条件。结果表明,虽然随渗流速度增加,扩散系数增加,但对浓度分布几乎没有影响;而且在精度要求不高,物理扩散较小时,数值稳定性好的对流方程的数值弥散可以代替物理扩散。

In this paper a semi-analytical solution is presented for diffusion-convection equations. The solution is compared with numerical solution of convection equation. Then this paper studied the effect of diffusion coefficient on concentration distribution and the conditions of substitution with numerical dispersion for physical diffusion. The results show that the velocity almost has no effect on concentration distribution and generally the numerical dispersion can be substituted for physical diffusion.