You specify the inflow of gas through the inlet boundary as a parabolic
velocity profile as given by Eqn. (5243). The velocity profile is formulated in terms of two parameters: the step
height
and the maximum velocity
.
You set the turbulent length scale at the inlet to 5% of the
inlet width. To facilitate correct adaption when changing the step height, the turbulent
length scale is parameterized as:To set up the boundary conditions:-
Create a parameter to define the value of the maximum velocity:
-
Right-click the node and select .
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Rename the new scalar parameter to Vmax.
-
Edit the Vmax node and set the following
properties:
Property |
Value |
Value |
1.0 |
|
1 |
-
Create a field function to define the parabolic velocity profile:
-
Right-click the node and select .
-
Rename the new node to Parabolic Profile.
-
Edit the node and set the following properties:
Property |
Setting |
Function Name |
parabolicProfile |
Dimensions |
Velocity |
1 |
Definition |
${Vmax}*($${Position}[1]-${StepHeight})*(5*${StepHeight}-$${Position}[1])/(${StepHeight}*${StepHeight})/4
|
-
Define the inlet boundary using a parabolic velocity profile:
-
Edit the node and set the Method to
Intensity + Length Scale.
-
Edit the node and set Value to
0.05*${StepHeight}*4.
-
Edit the node and set the following properties:
Property |
Setting |
Method |
Field Function |
Scalar Function |
Parabolic Profile |
-
Set the heat flux on the bottom wall:
-
Edit the node and set Condition to
Heat Flux.
-
Edit the node and set Value to
500 W/m^2
-
Save the simulation.