Setting convection parameters

The Convection parameters dialog enables you to define abortion criteria, intervals for updating the mesh and the view factors, ramps and solvers. The 4 tabs of this dialog correspond to these purposes: Abortion, Multiphase, Ramps and Solver.

  1. Select Computation > Convection parameters.

    The Convection parameters dialog opens.

    Convection parameters dialog, Abortion tab 

    Figure 57. Convection parameters dialog, Abortion tab

    The defaults in this dialog were obtained from experience and produce reasonable results.

  2. Change the specified interval to a constant underrelaxation factor by entering the same value 0.2 in the first two input fields for Underrelaxation Velocity factors (inc. from 0.2 to 0.2 between 10 and 0.01).

  3. Click on Apply.

  4. Click on the Multiphase tab.

    The Multiphase dialog opens.

    Convection parameters dialog, Multiphase tab 

    Figure 58. Convection parameters dialog, Multiphase tab

  5. On the Multiphase tab you specify the momentum when the mesh should be adjusted to the position of the interface.

    Change the Momentum to 0.4.

  6. Click on Apply.

  7. Click on the Ramps tab.

    The Ramps tab opens.

    Convection parameters dialog, Ramps tab 

    Figure 59. Convection parameters dialog, Ramps tab

  8. If you start from scratch and do not want to change the properties in the Materials dialog every time, you can run a ramp to approximate the real values. It is possible to run density, capacity and viscosity ramps.

    Click on the box in front of run a viscosity ramp to activate this function.

  9. Now you have to define steps for lowering viscosity.

    Replace the default start factor viscosity by 40 and the multiply factor per step by 0.8.

  10. Click on Apply.

  11. Click on the Solver tab.

    The Solver dialog opens.

    Solver dialog 

    Figure 60. Solver dialog

    The default solvers should not be changed.

  12. computation by clicking the Start computation  button.

    Click on Close.

Related Procedures

Setting Convection parameters

Related Dialogs

Convection parameters