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WORKSHOP: - Water pouring into a bund by SEM.

This workshop example shows how to set up and run the simulation of 3D transient free surface flow of water in air by Scalar Equation Model in PHOENICS-VR.

The task is to simulate the water pouring into a bund through the bottom slot at the right side wall. The opposite side wall has an opening through which the water leaks out of the bund. Internal obstacle is located on the water path.

It is expected that the water starts to propagate into the bund along the horizontal floor until it encounters the internal beam. It re-directs the water stream until it finally reaches the leak opening over-flowing the obstacle.

The geometry is shown in the figure below.

Accessing PHOENICS-VR

From the system level:

To enter the PHOENICS-VR environment, click on the PHOENICS icon on the desktop, or click on Start, programs, PHOENICS, PHOENICS.

From the commander level:

To enter the PHOENICS-VR environment, click on the 'Run vre' icon in the left column.

In PHOENICS-VR environment,

Start with an 'empty' case - click on 'File' then on 'Start New Case', then on 'Core', then click on 'OK'; to confirm the resetting.

To enter VR Editor:

This is the default mode of operation .

 

Within VR Editor.

Set the domain size, and activate solution of the required variables:

Click on 'Menu' and set 'Water pouring into a bund

Click on 'Geometry'.

Change the Z-Domain Size to 0.3 m.

Change the Number of cells to 12 cells in X, 28 in Y and 17 in Z.

Click on Time dependence STEADY to toggle to TRANSIENT.

Click on 'Time step settings'.

Set:

Click 'OK' to close the Time step settings dialog, then 'OK' to close the Grid mesh settings dialog.

Click on 'Models'.

Leave the 'Solution for velocities and pressure' ON.

Set the 'Free-surface model' to Scalar Equation.

Click on 'Top menu' to return to the top menu.

Click on 'OK' to exit the Main Menu.

Create the BEAM object:

Click on 'Settings', 'New' and 'New Object' on the top bar menu.

Change name to BEAM.

Click on 'Size' and set SIZE of object as:

Xsize: 1.0

Ysize: 0.1

Zsize: 0.06

Click on 'Place' and set POSITION of object as:

Xpos: 0.0

Ypos: 0.5

Zpos: 0.0

Click on 'General'.

Select Type: Blockage (default).

and on 'OK' to close the Object Specification Dialogue Box.

Create the WATER-IN object:

Click on 'Settings', 'New' and 'New Object' on the top bar menu.

Change name to WATER-IN.

Click on 'Size' and set SIZE of object as:

Xsize: 0.5

Ysize: 0.0

Zsize: 0.09

Click on 'General'.

Define Type: Inlet.

Click on 'Attributes' and set velocity in Y-direction at 5.0 m/s.

Set 'Inlet density' at 'Heavy' for the inflowing water.

Click on 'OK' to close the Attributes menu,

and on 'OK' in the Object Dialogue Box.

Create the OUTLET object:

Click on 'Settings', 'New' and 'New Object' on the top bar menu.

Change name to OUTLET.

Click on 'Size' and set SIZE of object as:

Xsize: 0.6

Ysize: 0.0

Zsize: 0.09

Click on 'Place' and set POSITION of object as:

Xpos: 0.2

Ypos: 1.0

Zpos: 0.0

Click on 'General'.

Define Type: Outlet.

Leave the default values in the Attributes dialogue box.

Click on 'OK' to exit the Object Dialogue Box.

Create the FREE-TOP object:

Click on 'Settings', 'New' and 'New Object' on the top bar menu.

Change name to FREE-TOP.

Click on 'Size' and set SIZE of object as:

Xsize: 1.0

Ysize: 1.0

Zsize: 0.0

Click on 'Place' and set POSITION of object as:

Xpos: 0.0

Ypos: 0.0

Zpos: 0.3

Click on 'General'.

Define Type: Outlet.

Leave the default values in the Attributes dialogue box.

Click on 'OK' to exit the Object Specification Dialogue Box.

Set the initial values and fluids distributions:

Click on 'Menu' and then on 'Initialisation'.

Set zero values for P1, U1,V1, W1 and SURN in the fields provided for 'FIINIT values', clicking > to go through the list of variables;

Set the properties of 'heavy' and 'light' fluids:

Click on 'Properties'.

To confirm that the light fluid material isn 'AIR at 20 deg C' and the heavy fluid material is 'Water at 20 deg C'.

Click on Propert 'Storage' and set 'ON' for Density and Viscosity, then on 'Previous panel' to get back.

Set gravity:

Click on 'Sources'.

Set 'Gravitational forces' ON and 'OK'.

Set 'Buoyancy model' to CONSTANT

Change 'Gravitational acceleration' to 0.0 in X and Y directions and -9.81 in Z.

Set the remaining solution-output-control parameters:

Click on 'Numerics'.

Set the number of iterations to 20.

Click on 'Relaxation control'.

Set relaxations for P1 to -0.5, U1,V1, W1 to 0.01 and SURN to 1 respectively, in the fields provided for 'DTFALS' Click on > to go through the list of variables;

Click on 'Previous panel'.

Click on 'Output'.

Change the monitoring point by setting

IXMON to 5,

IYMON to 5,

IZMON to 5.

Go into 'Field dumping' settings.

Change 'First step' to 1 and 'Last step' to 1000.

Change 'Step frequency' to 10.

Change 'Start letter for PHI' CSG1 to N

Click on 'Previous panel'.

Click on 'Top menu' to return to the top menu.

Click on 'OK' to exit the Main Menu.

Adjust the grid distribution

Click on 'Mesh toggle' button on the main control panel. The grid will appear on the screen

Click on the mesh on the screen to bring up the 'Grid mesh settings' dialog.

Set the cell numbers in each region as follows:

X direction Region 1 = 2, Region 2=4, Region 3=4, Reion 4=2

Y direction Region 1 = 14, Reion 2=3, Region 3=11

Z direction Region 1 = 3, Region 2=2, Region 3=12

Click on 'OK' to close the Grid mesh settings dialog.

Running the Solver.

In the PHOENICS-VR environment, click on 'Run', 'Solver'(Earth), and click on 'Yes' to confirm running the Solcer.

 

Using the VR Viewer.

In the PHOENICS-VR environment, click on 'Run', 'Post processor', then GUI Post processor (VR Viewer).

Click on 'Use intermediate step files'/'OK'.

Click on 'C' (select a variable) button, and select DEN1.

Click on 'Run animation' button to display the results.

Saving the results.

In the PHOENICS-VR environment, click on 'Save as a case', make a new folder called 'BUND ' (e.g.) and save as 'CASE1' (e.g.).


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