The pressure equation formulation is space centered with an upstream formulation for the phases mobilities and is solved using a direct skyline solver. The 1D saturation equation is discretized using an
explicit finite difference scheme in time and an upstream formulation in space.
怎么翻译啊?高手指点哈,谢谢!
尤其是其中的an upstream formulation 和 direct skyline solver。多谢了