507 Mechanical Movements

480

Another kind of gasometer

Another kind of gasometer. The vessel, A, has permanently secured within it a central tube, a, which slides on a fixed tube, b, in the center of the tank.

Only the input is driven; every other part of this model moves by physics (MuJoCo), and its ratios are measured. Run it live, change its parameters, or switch the friction off to see the output stop.

Modelled as
Seen from in front, the tank and the gasometer cut away in half section, gravity on. The gasometer A (34 cm inside, 2 kg, no counterweight) stands open-bottomed in a tank of water. A tube a, fixed inside its crown, slides on a fixed tube b in the middle of the tank, which keeps A upright. The works' supply (600 Pa) is the input; the gas under A is a lumped gas vessel and goes out to the burners through a cock that is swung slowly open and shut.
Measured
A's weight holds the gas at about 216 Pa. A rises on b while the cock is shut and sinks when it is open, and the water inside A stands lower than outside by the gas pressure. The water and the gas are drawn from the sim state. The motion gate passes.
Notes
Grade B. A drifts upward slightly over the run. The gate's WARN for 38% unexplained motion comes from the water's surface following A. Swinging the cock stands in for a changing draw.

Film (MP4) · Still (PNG) · Spec (YAML) · Model (MJCF)

Figure 480 from Brown, 1868
Brown's figure 480 (1868)