The efficiency of an impulse turbine is maximum when (where Vb = Blade speed, V = Absolute velocity of steam entering the blade, and `alpha` = Nozzle angle)
For a Parson's reaction turbine, if `alpha_1` and `alpha_2` are fixed blade angles at inlet and exit respectively and `beta_1` and `beta_2`are the moving blade angles at entrance and exit respectively, then
In
a Parson's turbine stage, blade velocity is 320 m/s at the mean radius
and rotor blade exit angle is `30^circ``For minimum kinetic energy of the
steam leaving the stage, the steam velocity at the exit of the rotor
will be
The maximum efficiency of a De-Laval turbine is (where `alpha` = Nozzle angle)
The maximum efficiency of a reaction turbine is