Approximate Methods for Plane Steady Flow

In this chapter some approximate methods for the solution of plane steady groundwater flow problems are presented. These are the graphical method of sketching flow nets, the numerical method of finite differences, and the method of fragments. A powerful and popular approximate method, the finite element method, is treated separately, in chapter 8. Approximate methods not treated explicity in this book are the method of boundary elements (Banerjee and Butterfield, 1977; Brebbia, 1978; Van der Veer, 1978), and the method of singularity distributions (De Josselin de Jong, 1960; Strack, 1980; Haitjema, 1980). These are numerical methods that can be considered as alternatives for the finite element method.