论文标题
各向异性扭曲了固定体积的多孔重力电流的扩散
Anisotropy distorts the spreading of a fixed volume porous gravity current
论文作者
论文摘要
我们考虑在各向异性多孔培养基中的释放和随后的重力驱动的散布，该介质受不可渗透的底物界定。当垂直方向上的渗透率远小于水平方向，就像许多实际地质储层一样，这限制了电流到底座附近非常薄的层的扩散。使用渐近分析和Darcy流的有限差分计算的组合，我们表明存在两个不同的流程度。在早期，大部分电流会缓慢而均匀地下降，将液体注入底座附近的薄手指状区域。在很久以后的时间，当前向经典重力驱动的溶液的过渡继续以自相似形状扩散。一个有趣的结果是，由于培养基的各向异性，电流的扫描体积的增长不同。这对于管理污染物溢出物有重要的后果，在此重要的是，将含水层的接触量最小化或在地质Co $ _2 $固存期间最小化，在此期间，较大的接触量会导致更多的co $ _2 $存储。
We consider the release and subsequent gravity-driven spreading of a finite volume of fluid in an anisotropic porous medium bounded by an impermeable substrate. When the permeability in the vertical direction is much smaller than the horizontal direction, as is the case in many real geological reservoirs, this restricts the spread of the current to a very thin layer near the impermeable base. Using a combination of asymptotic analysis and finite difference computations of Darcy flow, we show that there exist two distinct flow regimes. At early times the bulk of the current descends slowly and uniformly, injecting fluid into thin finger-like regions near the base. At much later times the current transitions to the classical gravity-driven solution and continues to spread with a self-similar shape. One interesting consequence is that the swept volume of the current grows differently depending on the anisotropy of the medium. This has important consequences for managing contaminant spills, where it is important to minimise the contacted volume of the aquifer, or during geological CO$_2$ sequestration where a larger contacted volume results in more CO$_2$ being stored.
