Page 175 - TransAT_Tutorial_Manual

TransAT Tutorial Manual 4.4. Film Boiling

• For Time Stepping select Adaptive then click

• Set the following parameters in the Adaptive Time-Stepping window then click to save
the settings and close the window
CFL Limits : Min : 0.5 Max: 0.9
D if fu s i o n : Min : 0.5 Max: 0.9
Surface Tension : Min : 0.5 Max: 0.9
Fourier Number : Min : 0.5 Max: 0.9

Equations
In the Equation section, the convergence threshold is defined, as well as the convection scheme
and the solvers used by TransAT.

• Select Other Variables in the equation tree

• Modify the parameters to the right of the equation tree as follows

Convergence Tolerance : 1.0 e−3

• Select Level-set in the equation tree

• Modify convection scheme as follows

Convection Scheme : QUICK

• Select Pressure in the equation tree
• Modify the parameters to the right of the equation tree as follows

Convergence Tolerance : 1.0 e−2
Solver : AMG R−cycle , adaptive

Initial Conditions
In the Initial Conditions tab, the initial conditions for the simulation are set. In this tutorial
advanced initial conditions are used.

For two–phase flow simulations, the initial gas–liquid interface topology has to specified by the
user. This is achieved in TransAT by using the initialconditions.cxx C++ file. More informa-
tion can be found on the generation of custom initial conditions in the Custom Initial Conditions
chapter of the TransAT User Manual.

c
Ascomp AG Switzerland 165 Version 5.7