Invariant solutions and conservation laws for soil water redistribution and extraction flow models
Abstract
In this dissertation we use Lie symmetry analysis to obtain invariant solutions for
certain soil water equations. These solutions are invariant under two-parameter
symmetry groups obtained by the group classification of the governing equation. We
also obtain all nontrivial conservation laws for a class of (2+1) nonlinear evolution
partial differential equations which are related to the soil water equations. It is shown
that nontrivial conservation laws exist for certain classes of equations which admit
point symmetries. We note that one cannot invoke Noether's theorem here as there
is no Lagrangian for these partial differential equations.