Quality coming out of the turbine

[scott_for_the_game]

Another question. If your given the quality coming out of the turbine.

Why do you use say H2 = Hl + xv(Hv - Hl) to determine a xv even though u have one given?

 

[Astronuc]

Another question. If your given the quality coming out of the turbine.

Why do you use say H2 = Hl + xv(Hv - Hl) to determine a xv even though u have one given?

Well in a saturated 2 phase state, the total enthalpy is determined by the enthalpy in the liquid fraction and the enthalpy in the vapor one.

h = (1-x) h_l + x h_v = h_l + x (h_v - h_l) where x is the thermodynamic quality.

Normally in a turbine, the steam entering is superheated and becomes saturated as work is extracted (momentum transfered) from the working fluid to the rotor and stator blades.