What is Kaplan turbine?
What is Kaplan turbine?
A Kaplan turbine is basically a propeller with adjustable blades inside a tube. It is an axial-flow turbine, which means that the flow direction does not change as it crosses the rotor.
What is the principle of Kaplan turbine?
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.
What is Kaplan turbine used for?
A Kaplan turbine is a type of propeller hydro turbine (specifically a reaction turbine) used in hydroelectric plants. Water flows both in and out of Kaplan turbines along its rotational axis (axial flow).
Why is Kaplan turbine high efficiency?
Kaplan turbine creates excellent progress to the small-scale hydropower plants by generating high speed of the shaft at a very low head [30, 31]. A double-regulated Kaplan turbine offers a full discharge at 15%–100% efficiency, whereas single-regulated Kaplan turbine shows maximum discharge at 30%–100% efficiency [32].
What is the efficiency of Kaplan turbine?
The hydraulic efficiency of a Kaplan turbine is 95%, the mechanical efficiency is 93% and the volumetric efficiency is assumed to be 100%.
What is the difference between Francis and Kaplan turbines?
Efficiency of Kaplan turbine is higher than Francis turbine. Kaplan turbine is more compact in cross-section and has lower rotational speed to that of Francis turbine. In Kaplan turbine, the water flows axially in and axially out while in Francis turbine it is radially in and axially out.
What is the working principle of a Kaplan turbine?
Working Principle of the Kaplan Turbine: Kaplan turbine is an axial flow reaction turbine. So the working fluid changes the pressure as it moves across the turbine and gives energy. Power recapitulates from both the Hydrostatic head and kinetic energy of the following water.
How are guide vanes used in a Kaplan turbine?
Guide vanes are used to direct the water to the runner blades smoothly by decreasing its swirl velocity. If guide vanes is absent than the turbine can not work efficiently and its efficiency decreases. The guides are adjustable in Kaplan turbine. Its opening and closing depends upon the demand of power requirement.
How does scroll casing work on Kaplan turbine?
1. Scroll Casing It is a spiral type of casing that has decreasing cross section area. The water first enters into the scroll casing and then it moves through it to the guide vanes and finally to the runner blades. It protects the runner, runner blades guide vanes and other internal parts of the turbine from an external damage.
When was the Kaplan turbine runner wheel invented?
reaction where Kaplan t urbine is a reaction type which was invented in 1913. The efficiency o f a turbine is highly influenced by its runner wheel and this work aims to study the design of a Kaplan turbine runner wheel. First, a theoretical design was performed fo r determining the main characteristics where it sho wed an efficiency of 94%.