Curtis turbine - how does it work

The principle of operation of a Curtis turbine:
- Curtis turbine is a type of impulse turbine
- curtis turbine has 2 sets of moving blades separated by 1 set of stationary blade
- rotating (moving) blades are attached to the turbine rotor
- fixed (stationary) blades are attached to the turbine casing

- Curtis turbine arrangement is as follows: (see picture)
  a.  nozzle
  b.  first set (ring) of moving blades ---> M
  c.  set of stationary (fixed) blades ----> F
  d.  second set of moving blades ------> M

Fig. 1.  Curtis wheel turbine having 2 sets of rotating blades with
            1 set of fixed blades in between.  (by Subik Kumar):

- nozzle: converts high pressure energy of the steam into high velocity kinetic energy
- first ring of moving blades: gains momentum force and rotates while steam velocity is reduced
- set of fixed blades: guides the steam to flow with same velocity to the second set of moving blades
- second set of moving blades: rotates while steam velocity is reduced

- steam pressure is reduced through the nozzle only
- steam pressure remains the same after the nozzle as it passes through moving and fixed blades
- steam velocity is reduced after it passes through the moving blades
- steam velocity is constant as it passes through fixed blades