FVICs System

Description

The FVICs block within an input file is used to define the initial (starting) conditions for the finite volume variables within your simulation. Initial conditions may be applied to both the "unknowns" (nonlinear) or auxiliary variables. It computes the values of the variable at the cell centroids.

FVICs Block

The preferred syntax is to create a top-level "FVICs" block with subblocks defining the initial conditions for one or more variables.

[FVICs]
  [u_ic]
    type = FVFunctionIC
    variable = 'u'
    function = parsed_function
  []
[]
(moose/test/tests/fvics/function_ic/parsed_function.i)

FVICs from an Exodus File

MOOSE contains a shortcut syntax for reading solutions from an Exodus file for the initial condition from right within the Variables. The name of the variable and the time step from which to read the solution must be supplied.

[Variables]
  [u]
    type = MooseVariableFVReal
    initial_from_file_var = u
  []
[]
(moose/test/tests/fvics/file_ic/file_restart.i)

Sanity checks on FVICs

  • Multiple FV initial conditions may not be applied to the same variable on the same block

  • Global initial conditions will conflict with subdomain or boundary restricted ICs on the same variable

Available Objects

  • Moose App
  • FVConstantICSets a constant field value.
  • FVFunctionICAn initial condition that uses a normal function of x, y, z to produce values (and optionally gradients) for a field variable.

Available Actions