Water Mill Lab: Overshot and Undershot Wheels, Gearing and Millstones Blender 5.2

Falling water turns a wooden wheel, wooden gears speed it up about fifteen times, and a pair of stones grinds the grain. Change the stream, the wheel and the gearing and watch the power flow. Drag to look around; the buttons below the picture jump to the wheel, the gears and the stones.

Presets

Stream and wheel

Stream flow Q

Head (pond level above tail water) H

Gearing and millstones

Stone nut staves (lantern pinion)

Stone gap (grinding clearance)

Feed gate (shoe opening)

Auto-refill hopperSpin-up

Live readouts

Where the power goes

Hydraulic power rho g Q H split into water losses, bearings, wooden gears, idle stone friction and useful grinding.

Graphs

Wheel power against wheel speed (marker: operating point where the stones' torque meets the wheel's)

Last 60 s: millstone speed (amber) and flour output (green)

Flour particle sizes (mass distribution, log scale) with the 250 micrometre sieve

Experiment: which wheel suits this stream?

A design office run: for a stream flow and a fall, each wheel type is sized (diameter, width) and run at its best speed. The numbers are compared with textbook efficiencies and a rule of thumb.

Stream flow

Fall (head)

Best efficiency against fall for this flow. Gaps are falls where the wheel type is not practical.

Independent numerical checks

View and quality

Roof Front wall Wheel-side wall Stone-floor boards

See water in the buckets Labels

Quality

High is the default on every device. Low lowers resolution and shadow detail (also ?q=low).

The science