What is the working principle of Francis turbine?
What is the working principle of Francis turbine?
In a Francis turbine, runner blades are divided into 2 parts. The lower half is made in the shape of a small bucket so that it uses the impulse action of water to rotate the turbine. The upper part of the blades uses the reaction force of water flowing through it. These two forces together make the runner rotate.
What is the efficiency of Francis turbine?
Finally, the optimal scheme of the new Francis turbine was proven to have a high efficiency of 88% and good operation stability through testing of a physical model and can achieve the goal of harvesting renewable energy in the cooling tower.
Which type of turbine is Francis?
reaction turbine
The Francis turbine is a reaction turbine, which means that the working fluid changes pressure as it moves through the turbine, giving up its energy. The turbine is located between the high-pressure water source and the low-pressure water exit, usually at the base of a dam.
What is speed ratio of Francis turbine?
It is defined as the ratio of tangential velocity or circumferential velocity to its spout velocity and denoted b. ϕ = U 1 2 g H Where, U1 = Tangential velocity, 2 g H = Spout velocity….Detailed Solution.
| Turbine Name | Specific Speed (NS), MKS |
|---|---|
| Francis turbine | 60 – 300 |
| Kaplan turbine | > 300 |
Where is Francis turbine used?
hydroelectric power plants
Operation. Francis turbines are used frequently in hydroelectric power plants. In these plants, high pressure water enters the turbine through the snail-shell casing (the volute). This lowers the pressure as the water curls through the tube, but the speed of the water is maintained.
What is the specific speed of Francis turbine?
The Francis Turbines specific speed is medium (60-300 rpm) and Kaplan Turbines specific speed is high (300-1000 rpm).
Is Francis turbine axial flow?
The Francis turbine is a type of water turbine. It is an inward-flow reaction turbine that combines radial and axial flow concepts. Francis turbines are the most common water turbine in use today, and can achieve over 95% efficiency.
