radopt

Mapdl.radopt(fluxtol='', solver='', maxiter='', toler='', overrlex='', maxfluxiter='', **kwargs)

Specifies Radiosity Solver options.

APDL Command: RADOPT

Parameters:

fluxtol

Convergence tolerance for radiation flux. Defaults to 0.0001. This value is a relative tolerance.

solver

Choice of solver for radiosity calculation:

0

Gauss-Seidel iterative solver (default).

1

Direct solver.

2

Jacobi solver.

maxiter

Maximum number of iterations for iterative solver (SOLVER = 0 or 2). Defaults to 1000.

toler

Convergence tolerance for the iterative solver (SOLVER = 0 or 2). Defaults to 0.1.

overrlex

Over-relaxation factor applied to the iterative solver (SOLVER = 0 or 2). Defaults to 0.1.

maxfluxiter

Maximum number of flux iterations to be performed according to the specified solver type:

0

If the FULL solver is specified (THOPT,FULL), convergence criteria are monitored and iterations are performed until convergence occurs. If the QUASI solver is specified (THOPT,QUASI), convergence criteria are ignored and one iteration is performed. This value is the default.

1, 2, 3, …N

If the FULL solver is specified (THOPT,FULL), convergence criteria are monitored and iterations are performed until convergence occurs, or until the specified number of iterations has been completed, whichever comes first. If the QUASI solver is specified (THOPT,QUASI), convergence criteria are ignored and the specified number of iterations are completed.

Notes

The radiation heat flux is linearized, resulting in robust convergence.

The radiation flux norm for FLUXTOL is expressed as:

where i is the pass or iteration number and j is the surface facet for radiation.

For a sufficiently small absolute tolerance value, relative tolerance converges in fewer iterations than absolute tolerance. For a sufficiently large absolute tolerance value, relative tolerance may cause convergence difficulties.

For more information about FLUXTOL and MAXFLUXITER usage, see Figure: 3.5:: FULL Solution Method When Radiosity Is Present and Figure: 3.6:: QUASI Solution Method When Radiosity Is Present in the Thermal Analysis Guide.

In Figure: 3.5:: FULL Solution Method When Radiosity Is Present and Figure: 3.6:: QUASI Solution Method When Radiosity Is Present (under Solving for Temperature and Radiosity in the Thermal Analysis Guide), refer to the KQQ = FQ equation system via the iterative method:

If TOLER ≥ 0, the iterative solver is converged for maximum value over a different j as shown:

If TOLER < 0, the iterative solver is converged for maximum value over a different j as shown:

where:

The Jacobi solver (SOLVER = 2) is suitable when using Distributed ANSYS. This option is only available for 3-D models; if SOLVER is set to 2 for a 2-D analysis, the Gauss-Seidel iterative solver (SOLVER = 0) is used.