Turbine - A neat differentiation
- 1. FLUID MECHANICS AND MACHINERY
- 2. TURBINE
- 3. What is a TURBINE??? A turbine is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful work. A turbine is a turbomachine with at least one moving part called a rotor assembly, which is a shaft or drum with blades attached. Moving fluid acts on the blades so that they move and impart rotational energy to the rotor.
- 4. • Credit for invention of the steam turbine is given both to the British engineer Sir Charles Parsons (1854–1931), for invention of the reaction turbine and to Swedish engineer Gustaf de Laval (1845–1913), for invention of the impulse turbine • The word "turbine" was coined in 1822 by the French mining engineer Claude Burdin from the Latin turbo, or vortex
- 5. An example : Wind Turbine
- 6. WORKING PRINCIPLE: • The working principle is very much simple. • When the fluid strikes the blades of the turbine, the blades are displaced, which produces rotational energy. • When the turbine shaft is directly coupled to an electric generator , mechanical energy is converted into electrical energy. • This electrical power is known as hydroelectric power.
- 7. TYPES: According to the action of the water flowing 1.Impulse turbine e.g Pelton Wheel 2.Reaction turbine e.g Francis turbine, Kaplan turbine.
- 9. Impulse Turbine • In an impulse turbine the potential energy, or the head of water, is first converted into kinetic energy by discharging water through a carefully shaped nozzle. The jet, discharged into air, is directed onto curved buckets fixed on the periphery of the runner to extract the water energy and convert it to useful work.
- 10. Reaction Turbine
- 11. Reaction Turbine • In a reaction turbine, forces driving the rotor are achieved by the reaction of an accelerating water flow in the runner while the pressure drops. The reaction principle can be observed in a rotary lawn sprinkler where the emerging jet drives the rotor in the opposite direction.
- 12. Pelton Wheel
- 13. Pelton Wheel • It was invented by Lester Allan Pelton in the 1870s. • Nozzles direct forceful, high-speed streams of water against a rotary series of spoon-shaped buckets, also known as impulse blades, which are mounted around the circumferential rim of a drive wheel— also called a runner
- 14. Applications • Pelton wheels are the preferred turbine for hydro-power, when the available water source has relatively high hydraulic head at low flow rates, where the Pelton wheel is most efficient. • Pelton wheels are made in all sizes. • There exist multi-ton Pelton wheels mounted on vertical oil pad bearings in hydroelectric plants.
- 15. Francis Turbine
- 16. Francis Turbine • The Francis turbine is a type of water turbine that was developed by James B. Francis in Lowell, Massachusetts. • The Francis turbine is a type of reaction turbine, a category of turbine in which the working fluid comes to the turbine under immense pressure and the energy is extracted by the turbine blades from the working fluid
- 17. • . A part of the energy is given up by the fluid because of pressure changes occurring in the blades of the turbine, quantified by the expression of Degree of reaction, while the remaining part of the energy is extracted by the volute casing of the turbine. At the exit, water acts on the spinning cup-shaped runner features, leaving at low velocity and low swirl with very little kinetic or potential energy left. The turbine's exit tube is shaped to help decelerate the water flow and recover the pressure.
- 18. Application • Francis type units cover a head range from 40 to 600 m (130 to 2,000 ft), and their connected generator output power varies from just a few kilowatts up to 800 MW. • Large Francis turbines are individually designed for each site to operate with the given water supply and water head at the highest possible efficiency, typically over 90%. • In addition to electrical production, they may also be used for pumped storage, where a reservoir is filled by the turbine (acting as a pump) driven by the generator acting as a large electrical motor during periods of low power demand, and then reversed and used to generate power during peak demand
- 19. Kaplan Turbine
- 20. Kaplan Turbine • The Kaplan turbine is a propeller-type water turbine which has adjustable blades. It was developed in 1913 by the 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.
- 21. • 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 directed tangentially through the wicket gate and spirals on to a propeller shaped runner, causing it to spin. • The outlet is a specially shaped draft tube that helps decelerate the water and recover kinetic energy.
- 22. Applications • Kaplan turbines are widely used throughout the world for electrical power production. They cover the lowest head hydro sites and are especially suited for high flow conditions. • Inexpensive micro turbines on the Kaplan turbine model are manufactured for individual power production with as little as two feet of head. • Large Kaplan turbines are individually designed for each site to operate at the highest possible efficiency, typically over 90%. They are very expensive to design, manufacture and install, but operate for decades.