这是化学/石油工程师的有限体积（玩具）工具箱。
现在，它可以解决一个瞬变对流扩散方程的变速场/扩散系数。 离散化方案
包括：
?? * 中心差异扩散项
?? * 中央差分对流项
?? * 逆风对流期
?? * TVD对流项与各种流量限制器
?? * 瞬态项
?? * Dirichlet，Neumann，Robin和周期性边界条件(This is a finite volume (toy) toolbox for chemical/petroleum engineers.
Right now, it can solve a transient convection-diffusion equation with variable velocity field/diffusion coefficients. The discretization schemes
include:
　* central difference diffusion term
　* central difference convection term
　* upwind convection term
　* TVD convection term with various flux limiters
　* transient term
　* Dirichlet, Neumann, Robin, and periodic boundary conditions)