Question

(thermodynamics) i need help with questions 5,6,7

5 Consider a steam power plant that operates on a simple ideal Rankine cycle and has a net power output of 45MW. Steam enters the turbine at 7 MPa and 0Cand is cooed in the condenser at a pressure of 10 kPa by nuning cooling watr from a lake through the tubes of the condenser at a nte of 2000 kgs Show the cycle on a T-s diagam with respet to saturation lines, and detemine (a) the thermal ficiency of the cyele, ()the mass flow rate of the steam, and ()the temperature rise of the cooling water 6 An adiabatic air compressor is to be powered by a direct-coupled adiabatic steam turbine that is also driving a generator. Steam enters t turbine at 12.5 MPa and 500°C at a rate of 25 kg's and exits at 10 kPa and a quality of 0.92. Air enters the compressor at 98 kPa and 295 at a rate of 10 kg/s and exits at 1 MPa and 620 K. Detemine the net power delivered to the generator by the turbine I MPa 620 K 125 MPa 500 C Steam turbine Air comp 10 KPa 98 kPa 295 K 7 Refrigerant-134a enters an adiabatic compressor at 15 psia and 20 F with a volume flow rate of 10 fts and leaves at a pressure of 100 psia. The power input to the compressor is 45 hp. Find (a) the aass flow rate of the refrigerant and (b) the exit temperature. P,100 psia R-134a 45 hp P 15 psia ,20H Figure PS-189E

Answer 1

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