In a reheat cycle steam at 500°C expands in H.P. turbine till it is saturated vapour. It is reheated at constant pressure to $400^oC$ and then expands in L. P. turbine to $40^oC$. If the maximum moisture content is limited to 15% at the turbine exhaust, - Mumbai university > MECH > SEM 3 > THERMO

Marks: 12M

Year: May 2014

Given: $T_3= 500^oC, T_5= 400^oC, T_6= 40^oC, x_6 = 0.85$

Solution:

At $40^oC$, from Steam tables,

$s_6 = sf_6 + x_6 × sfg_6$

= 0.572 + 0.85(7.686)

= 7.1051kJ/K

$h_6 = hf_6 + x_6 × hfg_6$

= 167.5 + 0.85(24069)

= 2213.365k/kg

Process 5-6 is isentropic,

$s_5 = s_6 = …