Drag coefficient slider:

Drag the slider to adjust the drag coefficient.

Adjustable compressor:

The empty boxes can be dragged vertically. By vertically dragging the empty box at the compressor, the pressure inside the container can be adjusted.
Notice how the diver slowly moves down in the simulation after being compressed.

Adjustable diver velocity:

The velocity of the diver can also be altered by dragging the red arrow/box vertically.
Notice how the velocity of the diver will automatically re-adjust accordingly due to the compression.

Credits:

Fu-Kwun Hwang; Fremont Teng; Loo Kang Wee @ iwant2study.org.