Application of Archimedes's screw to raising water
Application of Archimedes’s screw to raising water, the supply stream being the motive power. The oblique shaft of the wheel has extending through it a spiral passage, the lower end of which is immersed in water, and the stream, acting upon the wheel at its lower end, produces its revolution, by which the water is conveyed upward continuously through the spiral passage and discharged at the top.
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, left and above, as Brown, gravity on. An oblique shaft rising 35 degrees, 50 cm long, has a spiral passage coiled through it (1.9 cm out, 5 cm a turn, 9 turns; the shaft's casing is drawn as a cage of hoops and staves so the passage shows), and on its foot a paddle wheel of 8 boards (3.3-8 cm out, 5 cm along the shaft) whose lowest boards dip in the stream. The stream is particle water in its own plane (a slab 14.5 cm deep, kept 10 cm deep upstream); the boards, out of that plane, are cut by it afresh every step (fluid.cut) and pushed for the depth of the slab they span. Each turn every coil's pocket (the water at the coil's low point) moves up a coil (vessels.screws, 5 cm3 a turn): from the stream into the first, each into the next, and out of the passage's mouth 29 cm above the stream into a trough, which runs out at its far end; the shaft is loaded by that lift. The stream is the only input. gen443.py.
- Measured
- The wheel turns the stream's way at about 3.9 rad/s mean (0.6 turn/s), unevenly as the boards meet the water; the screw delivers about 3 g/s into the trough, whose water rises from 49 g as it runs out at its end. With no stream the shaft stands.
- Notes
- The casing is a cage rather than Brown's solid cylinder, so the passage and its pockets are seen. The pockets are drawn fixed at each coil's low point (where the water lies while the coils turn round it); they start full, as in a screw already running. The stream is as deep as the particle slab, narrower than Brown's river.
Film (MP4) · Still (PNG) · Spec (YAML) · Model (MJCF)
