The Segner Wheel

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Johann Andreas Segner

Johann Andreas Segner (Source: Wikipedia.org)

Johann Andreas Segner

9. 10. 1704, Pressburg (now Bratislava, Slovakia)

5. 10. 1777, Halle, Prussia (now Germany)

Segner János Andreás (or Ján Andrej Segner) was a German physicist, physician, astronomer, botanist, mathematician and inventor who is believed to be the first to come up with a rudimentary concept of a turbine. In 1747 he started publishing his first works in the field of hydraulics and turbine theory (Specimen theoriae turbinum, Halle 1755). Probably his best-known invention in this area is the so-called Segner wheel (1750).

The Segner Wheel

The whole design is basically a cylindrical vessel filled with water with several pipes at the bottom, stretching radially outwards, with nozzles on the ends that are all bent in the same direction. As water flows through the vessel and exits it at an angle through the pipes, the reactive force makes the whole vessel turn in a direction opposite to that of the exiting water. Though this machine never saw broad use, it was an important evolutionary step on the way to all the more modern types of turbines. Segner was probably also the first one to use a bent pipe for measuring the water speed.

Further improvements to the design of the Segner wheel were made by the mathematician Leonard Euler in that he led the water to the vessel in the direction of the rotation and at the same speed. According to a published report, the first application of the Segner wheel was to drive an oil pressing machine in a mill in Nörten, near Göttingen.

Rotating irrigation sprinkler systems are based on the principle of the Segner wheel. (Source: © meatbull / stock.adobe.com)

Rotating irrigation sprinkler systems are based on the principle of the Segner wheel.

Rotating irrigation sprinkler systems are based on the principle of the Segner wheel. (Source: © Nikitin Mikhail / stock.adobe.com)

Rotating irrigation sprinkler systems are based on the principle of the Segner wheel.

The principle of the Segner wheel is still used today in garden sprinklers.