Montgolfier’s hydraulic ram
Montgolfier’s hydraulic ram. Small fall of water made to throw a jet to a great height or furnish a supply at high level. The right-hand valve being kept open by a weight or spring, the current flowing through the pipe in the direction of the arrow escapes thereby till its pressure, overcoming the resistance of weight or spring, closes it. On the closing of this valve the momentum of the current overcomes the pressure on the other valve, opens it, and throws a quantity of water into the globular air-chamber by the expansive force of the air in which the upward stream from the nozzle is maintained. On equilibrium taking place, the right-hand valve opens and left-hand one shuts. Thus, by the alternate action of the valves, a quantity of water is raised into the air-chamber at every stroke, and the elasticity of the air gives uniformity to the efflux.
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 square from in front, as Brown. A head cistern (fed by a pour, the only input) drops through a drive pipe 63 cm long (2.4 cm bore) into a valve box full of water; on the box's top the waste valve (right: a disc on a stem with a ball, 3.5 cm of lift, held open by its weight, pushed shut by the box's pressure over the basin's; it throttles only in the last 0.8 cm, where the disc is near the seat) and the delivery valve (left: a check disc under the globe's neck); over that the globular air vessel (12 cm radius, air pre-charged) with the jet pipe dipping into its water and out of its mouth 40 cm up. The drive pipe's water has inertia (vessels links[].length, OpenSpec add-water-inertia): when the waste valve slams the column's momentum lifts the delivery valve and drives water into the globe; the recoil drops the box's pressure and the waste valve falls open. The basin round it runs away by a tail race. gen444.py.
- Measured
- Beats by itself about 1.3 times a second; the globe holds about 6.8 kPa (69 cm of water, 1.6 times the 42 cm fall) and throws a steady jet 0.13 kg/s; about 2.6 kg of the 9 kg let through is delivered in 20 s (sim trace).
- Notes
- The waste valve's lift (3.5 cm) is larger than a real ram's so that it can be seen beat; the throttling is only near the seat. The jet's arc is drawn from the recorded outflow. Grade B−.
Film (MP4) · Still (PNG) · Spec (YAML) · Model (MJCF)
