What is a Kaplan Turbine?
Kaplan turbine is a propeller type, axial flow water turbine. It has adjustable blades.
Adjustable blades help in obtaining good efficiency at wide range of head and discharge available to the turbine.
It is suitable for low head and high flow applications. It is an evolution of Francis turbine.
It is designed to operate where head is low unlike Francis turbine where it is not possible.
Operating parameters of Kaplan Turbine
Head: 10 m to 70 m
RPM: 54.5 to 429
Power output: 5 MW to 200 MW
Runner diameter: 2 m to 11 m
Working principle of Kaplan Turbine
The Kaplan turbine is an axial 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.
Parts of Kaplan Turbine
As shown in above diagram of Kaplan turbine, below are its important parts.
- Guide vanes or wicket gates
- Blade control mechanism
- Governing mechanism
- Scroll casing
- Draft tube
Applications of Kaplan Turbine
- At places were head is low and discharge is high
- Electrical power generation
Advantages of Kaplan turbine
- It can work at low head
- Number of blades is less
- It requires less space
- It has adjustable runner vanes
Disadvantages of Kaplan Turbine
- Cavitation is a problem
- High flow rate is required
- They are very expensive to design, manufacture and install
Below are some questions and answers related to the topic.
Who developed Kaplan Turbine?
Viktor Kaplan developed Kaplan turbine
What is the difference between Kaplan and Francis turbine?
Francis turbine is a mixed flow turbine whereas Kaplan is an axial flow turbine.
What is the difference between Kaplan and Pelton turbine?
Pelton turbine is an impulse turbine while Kaplan is a reaction turbine.
Parts: By Water_turbine_(en).svg: *Water_turbine.svg: U.S. Army Corps of Engineers (Vector image: Gothika)This W3C-unspecified vector image was created with Adobe Illustrator.derivative work: Mikhail Ryazanov (talk)derivative work: Old Moonraker (talk) – This file was derived from: Water turbine (en).svg:, Public Domain, https://commons.wikimedia.org/w/index.php?curid=18581340
Kaplan: By Voith Hydro Power Generation – Voith, Germany, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=459162