Defining Momentum Equation Controls

You can define controls to fine-tune the momentum equation solver.

Important: These controls are intended for expert users.

Before you begin:
See Also
About Equation Controls
  1. From the Linear solver options, select one of the following techniques for calculating the pre-conditioner matrix:
    OptionDescription
    DS-FGMRES Calculates the pre-conditioner matrix using the diagonally scaled flexible generalized minimum residual method.
    ILU-FGMRES Calculates the pre-conditioner matrix using the incomplete lower-upper factorization flexible generalized minimum residual method.

    The ILU-FGMRES linear solver is recommended for most simulations.

  2. Enter a value for the Iteration limit, which is the maximum number of iterations for the linear solver.
  3. Enter a value for the Convergence check frequency, which is the interval (in linear iterations) to check linear convergence.
  4. Enter a value for the Linear convergence limit, which is the point at which the iterative solver stops.

    The iterative solver stops when the relative residual norm of the system of equations and the relative correction of the solution norm fall below this convergence limit.

  5. Enter a value for the Number of restart vectors.

    The number of restart vectors is the number of times the solution is projected into a subspace before the subspace is rebuilt.