19.4.10. Postprocessing

1.Display the distribution of air on the XZ plane (Figure 19.4: Contours of Air Volume Fraction on the XZ plane (p. 668)).

+

Results → Graphics → Contours → Edit...

a.From the Contours of drop-down lists, select Phases... and Volume Fraction.

b.From the Phase drop-down lists, select air.

c.In the Surfaces selection list, deselect all surfaces by clicking and then select y=0, wall_impeller_1, and wall_impeller_2.

d.In the Options group box, make sure that Filled is selected.

e.Disable Global Range, Auto Range, and Clip to Range.

f.Enter 0.01 for Max.

The specified range will allow you to better view the volume fraction variation.

g.Clear Draw Mesh and then select this option again to open the Mesh Display dialog box.

vk.com/club152685050Using the Multiphase Models| vk.com/id446425943

i.In the Mesh Display dialog box, click next to the Surfaces filter to deselect all surfaces and then select wall_baffle_1, wall_sparger, and all walls whose names begin with 'wall_shaft'.

ii.Click Close to close the Mesh Display dialog box.

h.In the Coloring group box, select Smooth.

i.Click Display and use the interactive triad to orient the view as shown in Figure 19.4: Contours of Air Volume Fraction on the XZ plane (p. 668).

Note

You may need to deselect Lighting in the View ribbon tab (Display group).

Figure 19.4: Contours of Air Volume Fraction on the XZ plane

The contour map of the air volume fraction on the XZ plane shows how the air is agitated by impellers as it moves upward in the mixing tank. The shape of the Rushton blade turbine is forming cavities below the turbine.

2.Display the distribution of air on the plane z=0.08 (Figure 19.5: Contours of Air Volume Fraction on the z=0.08 plane (p. 669)).

a.In the Surfaces selection list, deselect y=0 and select z=0.08.

b.Click Display.

c.In the View Tools toolbar, from the Set View drop-down list (), select the view from the negative Z axis () to obtain the view shown in Figure 19.5: Contours of Air Volume Fraction on the z=0.08 plane (p. 669).

Note that the air is collecting on the bottom surface of the Rushton blade turbine disk before its dispersed by the impeller’s blades.

3.Display vectors of velocity magnitude for water on the XZ plane (Figure 19.6: Vectors of Water Velocity Magnitude on the XZ plane (p. 670)).

Results → Graphics → Vectors → Edit...

a.Select Velocity from the Vectors of drop-down list.

b.Select water from the Phase drop-down list.

Since the Eulerian model solves individual momentum equations for each phase, you can choose the phase for which solution data is plotted.

c.From the Color by drop-down lists, select Velocity... and Velocity Magnitude.

d.Retain the selection of water from the Phase drop-down list.

e.In the Surfaces selection list, deselect all surfaces by clicking and then select y=0, wall_impeller_1, and wall_impeller_2.

f.Click Display and use the interactive triad to orient the view as shown in Figure 19.6: Vectors of Water Velocity Magnitude on the XZ plane (p. 670).

vk.com/club152685050Using the Multiphase Models| vk.com/id446425943

Figure 19.6: Vectors of Water Velocity Magnitude on the XZ plane

The vector plot of the water velocity shows that the water moves in a circular motion, creating a closed loop since it cannot escape the reactor.

4.Display vectors of velocity magnitude for air on the XZ plane (Figure 19.7: Vectors of Air Velocity Magnitude on the XZ plane (p. 670)).

a.Under Vectors of, select air from the Phase drop-down list.

b.Under Color by, select air from the Phase drop-down list.

c.In the Surfaces selection list, make sure that y=0, wall_impeller_1, and wall_impeller_2 are selected.

d.Click Display.

Figure 19.7: Vectors of Air Velocity Magnitude on the XZ plane