4. Vertical Velocity versus Diameter (Full Screen)

 

 

The full screen representation of the diagram "Velocity versus Diameter" can be selected from the Main Screen by moving the mouse cursor on top of the according diagram icon and doubleclick the left mouse button.

 

4.1 Menu Buttons

 

button: RUN

Pushing this button draws the diagram for the given filter settings. A pixel is set for each drop at the corresponding (equivolumetric sphere diameter, velocity) position. The mouse cursor changes its appearance to an hourglass cursor in Run-mode, and the RUN button toggles to be the STOP button. Run-mode can be terminated by pressing the STOP button.

 

button: MAIN

Pushing this button returns control to the Main Screen.

 

button: HELP

Pushing this button displays this window.

 

button: COMP

If this button is pushed, two graphs taken from the literature and showing the relation between equivolumetric sphere diameter and drop velocity will be drawn.

 

4.2 Diagram Header

 

The diagram header contains information on filter settings and also includes the following fields:

 

 

4.3 Comparison with Literature Models

 

The graphs taken from the literature for velocity versus equivolumetric sphere diameter are:

 

4.3.1 Vertical velocity versus diameter after Atlas et al. (1973)

 

 

where:

v ...      vertical fall velocity of raindrop (m/s)

D ...     equivolumetric sphere diameter (mm)

 

4.3.2 Vertical velocity versus diameter after Gunn and Kinzer (1949)

 

Diam.

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

1.2

1.4

1.6

Veloc.

0.27

0.72

1.17

1.62

2.06

2.47

2.87

3.27

3.67

4.03

4.64

5.17

5.65

Diam

1.8

2.0

2.4

2.8

3.2

3.6

4.0

4.4

4.8

5.2

5.6

6.0

6.5

Veloc.

6.09

6.49

7.27

7.82

8.26

8.60

8.83

8.98

9.07

9.12

9.16

9.17

9.18