Transient transport problem - linear case

NonStationaryProblem nsteps(in) #
  [renumber(in) #]
  deltaT(rn) #
  alpha(rn) #
  [lumpedcapa() #]
  [sparselinsolverparams() #]
  [exportfields() #]
  [atomicfields(in) #]

Linear implicit integration scheme for transient transport problems. The generalized midpoint rule (sometimes called $\alpha$-method) is used for time discretization, with alpha parameter, which has limits $0\le\alpha\le1$. For $\alpha=0$ explicit Euler forward method is obtained, for $\alpha=0.5$ implicit trapezoidal rule is recovered, which is unconditionally stable, second-order accurate in $\Delta t$, and $\alpha=1.0$ yields implicit Euler backward method, which is unconditionally stable, and first-order accurate in $\Delta t$. deltaT is time step length used for integration, nsteps parameter specifies number of time steps to be solved. Nonzero value of optional parameter renumber turns on the equation renumbering to optimize the profile of characteristic matrix (uses Sloan algorithm). By default, profile optimization is not performed. It will not work in parallel mode. If lumpedcapa is set, then the stabilization of numerical algorithm using lumped capacity matrix will be used, reducing the initial oscillations. See section 6.17 for explanation of exportfields and atomicfields parameters. Note: This problem type requires transport module and it can be used only when this module is included in your oofem configuration.

Note: This problem type requires transport module and it can be used only when this module is included in your oofem configuration.

Borek Patzak 2009-08-24