Def of Turbine :
A turbine is a rotary engine that extracts energy from a fluid flow and converts it into useful work.
The simplest turbines have one moving part, a rotor assembly, which is a shaft or drum with blades attached. Moving fluid acts on the blades, or the blades react to the flow, so that they move and impart rotational energy to the rotor. Early turbine examples are windmills and water wheels.
Classification Of Turbines :
Turbines are classified in to may types, but they are mainly 2 types:
1)Impulse Turbines
2)Reaction Turbines
1)Impulse Turbines :
These turbines change the direction of flow of a high velocity fluid or gas jet. The resulting impulse spins the turbine and leaves the fluid flow with diminished kinetic energy. There is no pressure change of the fluid or gas in the turbine blades (the moving blades), as in the case of a steam or gas turbine, all the pressure drop takes place in the stationary blades (the nozzles).
Basic Principe:
The impulse turbine consists basically of a rotor mounted on a shaft that is free to rotate in a set of bearings.
The outer rim of the rotor carries a set of curved blades, and the whole assembly is enclosed in an airtight case.
Nozzles direct steam against the blades and turn the rotor.
2)Reaction Turbine :
These turbines develop torque by reacting to the gas or fluid's pressure or mass. The pressure of the gas or fluid changes as it passes through the turbine rotor blades. A pressure casement is needed to contain the working fluid as it acts on the turbine stage(s) or the turbine must be fully immersed in the fluid flow (such as with wind turbines). The casing contains and directs the working fluid and, for water turbines, maintains the suction imparted by the draft tube. Francis turbines and most steam turbines use this concept. For compressible working fluids, multiple turbine stages are usually used to harness the expanding gas efficiently. Newton's third law describes the transfer of energy for reaction turbines.
Basic Principle :
The ancient turbine built by Hero operated on the reaction principle.
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A turbine is a rotary engine that extracts energy from a fluid flow and converts it into useful work.
The simplest turbines have one moving part, a rotor assembly, which is a shaft or drum with blades attached. Moving fluid acts on the blades, or the blades react to the flow, so that they move and impart rotational energy to the rotor. Early turbine examples are windmills and water wheels.
Classification Of Turbines :Turbines are classified in to may types, but they are mainly 2 types:
1)Impulse Turbines
2)Reaction Turbines
1)Impulse Turbines :
These turbines change the direction of flow of a high velocity fluid or gas jet. The resulting impulse spins the turbine and leaves the fluid flow with diminished kinetic energy. There is no pressure change of the fluid or gas in the turbine blades (the moving blades), as in the case of a steam or gas turbine, all the pressure drop takes place in the stationary blades (the nozzles).
Basic Principe:
The impulse turbine consists basically of a rotor mounted on a shaft that is free to rotate in a set of bearings.
The outer rim of the rotor carries a set of curved blades, and the whole assembly is enclosed in an airtight case.
Nozzles direct steam against the blades and turn the rotor.
2)Reaction Turbine :
These turbines develop torque by reacting to the gas or fluid's pressure or mass. The pressure of the gas or fluid changes as it passes through the turbine rotor blades. A pressure casement is needed to contain the working fluid as it acts on the turbine stage(s) or the turbine must be fully immersed in the fluid flow (such as with wind turbines). The casing contains and directs the working fluid and, for water turbines, maintains the suction imparted by the draft tube. Francis turbines and most steam turbines use this concept. For compressible working fluids, multiple turbine stages are usually used to harness the expanding gas efficiently. Newton's third law describes the transfer of energy for reaction turbines.Basic Principle :
The ancient turbine built by Hero operated on the reaction principle.
Hero's turbine was invented long before Newton's time,but it was a working model of Newton's 3rd law of motion,
which states : "For every action there must be an equal and opposite reaction."
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