Finite difference methods applied to groundwater flow
Winifred L. Wood · 1993
Abstract This chapter discusses finite difference methods as used for problems of groundwater flow. Sections 5.2 and 5.3 discuss the elliptic boundary value problems obtained for a confined or unconfined aquifer after vertical integration and averaging. These may include abstraction or recharge wells and stream leakage. Section 5.4 considers the parabolic problems when the aquifers of sections 5.2 and 5.3 have time-dependent flow. Also in section 5.4 are brief descriptions of the IFDM (Integrated Finite Difference Method) for groundwater flow (Narasimhan and Witherspoon, 1976) and SHE (Système Hydrologique Européen) (Abbott et al., 1986) which is a finite difference method for combined surface and subsurface flow. Section 5.5 considers a particular problem of ‘noise’, i.e. unwanted oscillation that has occurred in the numerical model of an aquifer which includes ephemeral streams.