Visualizing Results

Training Guide > Multi-Phase Flow Tutorials > Cavitation Tutorial > Visualizing Results

Visualizing Results

Examine the final distributions of water and water vapor in the Scalar Scene 1, as shown below.

As expected, cavitation occurs at the nozzle entrance as a result of the low pressure region produced by the sharp corner and the accelerating flow.

It is possible to create a contour plot that approximately shows both the water and water vapor distributions by creating and plotting a new field function.

Open the Tools node and then right-click on the Field Functions node and select New Function

In the Properties window, change the Function Name to Volume Fraction (All Phases)

Click on the Definition box to open the custom editor. In the editor window, enter the following syntax:

$VolumeFraction1+2*$VolumeFraction2

Click OK to exit from the editor.

In the Scalar Scene 1 display, right-click on the color bar and select Volume Fraction (All Phases).

For this plotting technique to work, the legend scale should be fixed between 0 and 2.

Select the Scenes > Scalar Scene 1 > Displayers > Scalar 1 > Scalar Field node.

In the Properties window, change the Max property to 2 to display the contour plot shown below.

To a reasonable approximation, the blue and turquoise areas are predominantly occupied by air, the green areas predominantly by liquid water and the yellow, orange and red areas predominantly by water vapor.

Manipulating the results in this way provides a qualitative visual estimate of the spatial extent of each phase. However, the resulting plots are prone to inaccuracies in those places where air and water vapor occur together and also where the liquid water volume fraction is only slightly greater than the water vapor volume fraction. In a case such as this, the latter leads to an overprediction of the size of the region of high water vapor concentration.

To display velocity vectors:

Right-click on the Scenes node and select New Scene > Vector

The vector scene will appear in the Graphics window.

Save the simulation.

Return to CD-adapco STAR-CCM+ Index

Your Ad Here