Conditional Lie-B?cklund symmetries and invariant subspaces to nonlinear diffusion equations with source

摘要

This paper considers conditional Lie-B?cklund symmetries of the radially symmetric nonlinear diffusion equations with source. We obtain a complete list of canonical forms for such equations which admit higher-order conditional symmetries. As a consequence, the solutions of the resulting equations are constructed on the invariant subspaces admitted by the corresponding equations.