Category: Steam Turbines

1 Advantages 2 Limitations

Let u = circumferential or tangential linear velocity of blades    va1 = absolute velocity of steam at inlet of moving blade    va2 = absolute velocity of steam at outlet of moving blade    vw1 = velocity of whirl at the entry of moving blade       = va1 cos α1    vw2 = velocity of whirl at the exit of moving blade        = va2 cos α2    vf 1 = velocity of flow at inlet of moving…

If the entire pressure drop from boiler pressure to condenser pressure is carried out in a single stage nozzle, the velocity of steam entering the turbine blades will be very high and consequently, the turbine speed will be very high. Such high speed turbine rotors are not useful for practical purposes and a reduction gearing…

The comparison of impulse and reaction turbines is given in Table 7.1.   Table 7.1 Comparison of impulse and reaction turbines

On the basis of principles of operation, steam turbines are classified as follows:

A steam turbine works on the dynamic action of steam. Steam is caused to fall in pressure in a passage or nozzle. Due to this fall in pressure, certain amount of heat energy is converted into kinetic energy to give it high velocity. The high velocity steam impinges on the moving blades of the turbine…