Follow the explanation
Back to the model ↑How the parts work together
Meet the splitter
Pause and follow the jet to the orange bucket on the upper-left side of the runner. Orbit to inspect its central ridge. Two cups turn the water toward opposite sides, avoiding a sustained one-sided axial push in this symmetric model. Play again to watch the next bucket receive the jet.
Give the jet more head
Raise head from 200 to 400 m with the jet diameter fixed. The ideal jet speed rises by √2. Since the same opening now passes faster water, flow also rises by √2; incoming hydraulic power rises by 2√2.
Widen the jet
Return to 200 m and increase jet diameter. Its cross-sectional area grows with diameter squared, so doubling diameter would quadruple flow and ideal power at fixed head and speed ratio.
Match the runner to the jet
At low runner speed, buckets exert strong turning force but move slowly. Near jet speed, they capture little momentum. With a fixed 165° relative-flow turn and no bucket friction, this model peaks at a rim speed equal to half the jet speed. Actual turbine efficiency includes further losses.
The main parts
- Nozzle & spear
- The taper accelerates water into a free jet. A central spear regulates the opening in a real injector. Here the control specifies an effective circular jet diameter; the visible spear shift is illustrative, not a calibrated valve-flow model.
- Paired cups & splitter
- Each of the eighteen buckets has two concave cups meeting at a central ridge. The jet divides toward opposite sides of the shaft. Orange identifies the bucket meeting the center of the jet, so the highlight passes from bucket to bucket as the runner turns.
- Runner disc
- The bucket stems meet a common disc. All buckets turn rigidly with the disc and shaft. The geometry is an original teaching assembly with a half-metre pitch radius, not the CAD of a commercial runner.
- Shaft & coupling
- The shaft leaves the wheel perpendicular to its plane, passes through two bearings, and ends at a bolted coupling. Mechanical power is torque multiplied by angular speed. A generator is outside this cutaway.
- Two bearing supports
- Two bored housings support the shaft on opposite sides of the runner. Pedestals and feet connect them to the base. Bearing lubrication, friction and loads are not solved.
- Splash casing
- The casing catches discharged water. Its backplate has a real shaft opening; the cutaway removes the front face to expose the working parts. Unlike a reaction turbine, this runner is not submerged in a pressurized casing.
- Jet & split discharge
- Blue lines sample the width of the free jet and stop at their individual first bucket contacts. They represent paths, not solid cylinders of water. The two discharge ribbons indicate the split toward opposite sides; they are schematic direction cues, not computed water trajectories.
- Drain tray
- Spent water falls below the runner and leaves the open collection tray. The nozzle head is specified independently of this illustrative drain height.