The Kaplan turbine is a propeller-type water turbine which has adjustable blades. It was developed in 1913 by Austrian professor Viktor Kaplan, who combined automatically adjusted propeller blades with automatically adjusted wicket gates to achieve efficiency over a wide range of flow and water level.
The Kaplan turbine was an evolution of the Francis turbine. Its invention allowed efficient power production in low-head applications which was not possible with Francis turbines. The head ranges from 10 to 70 metres (33 to 230:ft) and the output ranges from 5 to 200 MW. Runner diameters are between 2 and 11 metres (6:ft 7:in and 36:ft 1:in). Turbines rotate at a constant rate, which varies from facility to facility. That rate ranges from as low as 54.5 rpm (Albeni Falls Dam) to 450 rpm.
Kaplan turbines are now widely used throughout the world in high-flow, low-head power production.On this Kaplan runner the pivots at the base of the blade are visible; these allow the angle of the blades to be changed while running. The hub contains hydraulic cylinders for adjusting the angle.
- 1 Development
- 2 Theory of operation
- 3 Applications
- 4 Variations
- 5 See also
- 6 References
- 7 External links
Viktor Kaplan, living in Brünn, Austria-Hungary (now Brno, Czechia), obtained his first patent for an adjustable blade propeller turbine in 1912. But the development of a commercially successful machine would take another decade. Kaplan struggled with cavitation problems, and in 1922 abandoned his research for health reasons.
In 1919 Kaplan installed a demonstration unit at Poděbrady (now in Czechia). In 1922 Voith introduced an 1100 HP (about 800:kW) Kaplan turbine for use mainly on rivers. In 1924 an 8 MW unit went on line at Lilla Edet, Sweden. This launched the commercial success and widespread acceptance of Kaplan turbines.
Theory of operationVertical Kaplan Turbine (courtesy Voith-Siemens).
The Kaplan turbine is an inward flow reaction turbine, which means that the working fluid changes pressure as it moves through the turbine and gives up its energy. Power is recovered from both the hydrostatic head and from the kinetic energy of the flowing water. The design combines features of radial and axial turbines.
The inlet is a scroll-shaped tube that wraps around the turbine's wicket gate. Water is direc... ...read more