Transition Boundary Distance Model Reference

The Transition Boundary Distance model allows you to calculate the distance from the field point to the nearest point on a transition boundary.

Model Name Transition Boundary Distance*
Theory See Theory Guide—Wall Distance.
Provided By [physics continuum] > Models > Transition Boundary Distance
Example Node Path Continua > Physics 1 > Models > Transition Boundary Distance
Requires
  • Turbulence: Reynolds-Averaged Navier-Stokes
  • Reynolds-Averaged Turbulence: any
  • K-Epsilon Turbulence, K-Omega Turbulence, Reynolds Stress Turbulence, Spalart-Allmaras Turbulence: any
  • Optional Models: Turbulence Suppression
Properties
  • Transition Boundary Distance Method
See Transition Boundary Distance Properties.
Activates Solvers
Field Functions
  • Transition Boundary Distance
  • Transition Boundary Distance Factor
See Field Functions.

Transition Boundary Distance Properties

Transition Boundary Distance Method
Sets the method that Simcenter STAR-CCM+ uses for computing the transition boundary distance.
The following options are available:
  • Implicit Tree (default): calculates the exact distance using an implicit tree algorithm.
  • PDE: estimates the distance using a partial differential equation.

Transition Boundary Distance Solver Properties

This solver controls the transition boundary distance solution for the Implicit Tree transition boundary distance method in all the continua for which the model is activated.

Solver Frozen
When On, the solver does not update any quantity during an iteration. It is Off by default. This is a debugging option that can result in non-recoverable errors and wrong solutions due to missing storage. See Finite Volume Solvers Reference for details.
Verbosity
Allows you to choose how much information Simcenter STAR-CCM+ reports in the Output window while the simulation is running. This property is useful for debugging problems when they occur. The only valid entries are 0 (default), 1, and 2:
  • 0 = None: Leaves output at its default.
  • 1 = Low: Displays CPU time statistics across cores for calculating the wall distance. It reports the mean, maximum, and minimum elapsed times in seconds.
  • 2 = High: Displays CPU time statistics (see low verbosity) and memory usage statistics across cores. This entry allows you to evaluate the memory consumption of all server processes that are relevant to the wall distance calculation:
    • max process peak—that is the maximum resident memory usage across cores.
    • max host peak—that is the maximum memory that is used on a node.
    • accumulated peak—that indicates the rough scalability in terms of required memory.

PDE Transition Boundary Distance Solver Properties

This solver controls the transition boundary distance solution for the PDE transition boundary distance method in all the continua for which the model is activated.

Maximum Iteration
Sets the maximum number of iterations the solver can use. The default is 10.
Solver Tolerance
Specifies the total relative solver residual. The default value is 0.01.
Under-Relaxation Factor
In order to promote convergence, this property is used to under-relax changes of the solution during the iterative process. If residuals show solution divergence and do not decrease, reduce the under-relaxation factor.
Verbosity
Allows you to choose how much information Simcenter STAR-CCM+ reports in the Output window while the simulation is running. This property is useful for debugging problems when they occur. The only valid entries are 0 (default) and 1:
  • 0 = None: Leaves output at its default.
  • 1 = Low: Displays convergence history for wall distance and CPU time information.
Reconstruction Frozen
When On, Simcenter STAR-CCM+ does not update reconstruction gradients with each iteration, but rather uses gradients from the last iteration in which they were updated. Activate Temporary Storage Retained in conjunction with this property. This property is Off by default.
Reconstruction Zeroed
When On, the solver sets reconstruction gradients to zero at the next iteration. This action means that face values used for upwinding (Eqn. (905)) and for computing cell gradients (Eqn. (917) and Eqn. (918)) become first-order estimates. This property is Off by default. If you turn this property Off after having it On, the solver recomputes the gradients on the next iteration.
Solver Frozen
When On, the solver does not update any quantity during an iteration. It is Off by default. This is a debugging option that can result in non-recoverable errors and wrong solutions due to missing storage. See Finite Volume Solvers Reference for details.
Temporary Storage Retained
When On, Simcenter STAR-CCM+ retains additional field data that the solver generates during an iteration. The particular data retained depends on the solver, and becomes available as field functions during subsequent iterations. Off by default.

Under-Relaxation Factor Ramp

The PDE Transition Boundary Distance > Under-Relaxation Factor Ramp node allows you to set and control a linear ramp for under-relaxation. For details, see Under-Relaxation Factor Ramp Reference.

AMG Linear Solver

The PDE Transition Boundary Distance > AMG Linear Solver node allows you to set the algebraic multigrid parameters for the turbulence solver. For details, see Algebraic Multigrid and AMG Linear Solver Properties.

Field Functions

Transition Boundary Distance
The transition boundary distance, which is defined as the distance from the field point to the nearest point on a transition boundary.
Transition Boundary Distance Factor
An integer number that is zero when the transition boundary distance is less than the wall distance, and unity when it is greater.