15 07 19sol

Pagina 1

Quesito 1 Data for part A net electric power output, MW 20 steam temp at turbine inlet 500 steam pressure at turbine inlet 80 boiler pressure drop, % 25 condenser pressure, bar 10 hydraulic pump efficiency 0.8 mech-el. Pump driver efficiency 0.95 turbine isentropic efficiency 0.9 mech-el turbine generator efficiency 0.97 boiler thermal efficiency 0.91 Data for Part B evaporation pressure, bar 90 HRSG pinch point temp diff, °C 10 HRSG heat losses,% 5 GT turbine oulet temperature, °C 600 GT net electric efficiency 0.35 Cp fumi, kJ/kg-K 1.08 Results of part A h1, kJ/kg 3399.373 from Mollier diagram s1, kJ/kgK 6.726379 from Mollier diagram h3iso, kJ/kg 2842.971 from Mollier diagram h3 2898.611 from def. of isentropic efficiency T3 230.0719 T3 is r ead from the Mollier diagram h4 762.6828 from sat. Steam tables p5, bar 106.6667 from boiler pressure drop definition: pin = pout /(1-%_press_drop) h5 774.7662 from enthalpy change in a pump: hout = hin + spec_vol ume*(pout-pin)/eta_hydraulic steam mass flow rate, kg/s 42.28158 imposing that Pel,net = mste am * (turbine_work*turbine_mech_el_eff - pump_work/pump_mech_el_eff) thermal power to heat user, MW 90.31044 thermal power to the cycle, MW 110.9725 from the energy balance o f the boiler: Qin_cycle = msteam*(hout-hin) fuel chemical power, MW 121.9478 from the definition of boiler ef ficiency Net electrical efficiency of the plant 0.164005 Pel_net_comb_cycl e / Fuel_chem_powerGT Thermal efficiency of the plant 0.740566 Qheat_user / Fuel_chem_p owerGT Results of part B evaporation temperature 303.3468 °C saturated liquid enthalpy 1363.651 kJ/kg from Mollier diagram QSH+EVA 86073.54 kW msteam*(h1-hsat,liq) mass flow rate of GT flue gases 292.6615 kg/s from the energy bala nce of the SH+EVA of the HRSG: mFG =…