ABSTRACT
In summary, steady equilibrium problems, mixed elliptic/parabolic problems, and mixed elliptic/hyperbolic problems can be solved as the asymptotic steady state solution of an appropriate unsteady propagation problem. For linear problems, the asymptotic steady state solution can be obtained in one or two steps by the BTCS method, which is the recommended method for such problems. For nonlinear problems, the BTCS method becomes quite time consuming, since several time steps must be taken to reach the asymptotic steady-state solution. The asymptotic steady state approach is a powerful procedure for solving difficult equilibrium problems and mixed equilibrium/propagation problems.
