Active Homeworks 202122

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ENERGY CONVERSION A 2021-22 3 ii. determined the state properties (T, p, h,and s) in all cycle points employing the necessary sim- plifying assumption and adopting reasonable performance parameters for the fluid machines; iii. compute the net electric power. Exercise 8 A geothermal well provides a two -phase water flow at: temperature of 150 °C, liquid quality of 60% and total mass flow rate of 100 kg/s. The vapor phase is s eparated from the liquid phase, then t he separated vapor is expanded in a turbine and condensed in a condenser. The previously-separated liquid and the condensed liquid are pumped to the well pressure, mixed together and injected underground. Please: i. sketch the overall process flow diagram and the cycle on the Ts diagram (2 points); ii. determine the net electric power assuming adequate performance parameters for the equip- ment (2 points); Exercise 12 (Active homework) Considering an industrial process comprising an exploitable flow of exhaust gases at a rate of 260 m3/s, temperature of 650 °C and pressure approximately equal to ambient, design a thermodynamic cycle for producing power employing either of two working fluids. In both cases , the approach temperature dif- ference on the primary heat exchanger is 50 °C and the condensation temperature is 30 °C. Additional information is provided by the table. A B Units Critical temperature 163.5 400 °C Critical pressure 1.8 10.0 MPa Molar mass 90 150 kg/kmol γ̅ (ideal gas) 1.05 - cp̅ (ideal gas) - 300 J/(kg K) Liquid density 800 1200 kg/m3 Isentropic enthalpy change accross the turbine 250 kJ/kg Effectiveness of preheating line or recuperator 95% Not present For the cases of both fluids, please: i. sketch accurately the cycle on the T-s diagram and the process flow diagram; ii. compute the…