Question

Heat supplied to raise steam in the boiler is 3000 KJ/kg while heat rejected by the system to

the cooling water in the condenser is 2000 KJ/kg. The turbine develops power of 1500 KW and

the work required to pump the condensate back into the boiler is 50 KW. Find the steam mass

flow rate.

Answer 1

Solution.

$Q_b=3000KJ/kg;$

$Q_c=2000KJ/kg;$

$W_t=1500KW;$

$W_p=50KW;$

$Q=Q_b-Q_c;$

$Q=3000KJ/kg-2000KJ/kg=1000KJ/kg;$

$W=W_t-W_p;$

$W=1500KW-50KW=1450KW;$

$\dfrac{W}{Q}=\dfrac{1450KW}{1000KJ/kg}=1.45kg/s;$

Answer:$\dfrac{W}{Q}=1.45kg/s.$