31 01 17 sol

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Dati: Da tabelle vapore/Mollier: Assunzioni: Esercizio 1: Gfumi = 100 kg/s Ta = 500 °C cp fumi = 1.1 kJ/kg/K peva = 40 bar pRH = 16 bar T5 = T7 = 450 °C DT sub cooling = 5 °C cp, liq sat 40 bar = 4.84 kJ/kg/K eta,is TV AP (5-6) = 88 % eta,is TV MP (7-8) = 90 % eta,is TV LP (8-10) = 87 % Te = 100 °C TA = 80 °C TE = 100 °C TF = TC = 120 °C p8= p9 = 2.7 bar p10 = p11 = p1 = 1.0 bar T1 = 90 °C cp,w at T 80-130°C = 4.2 kJ/kgK perdite termiche HRSG = 0.5 %Q a) h5 = 3331.0 kJ/kg s5 = 6.938 kJ/kgK h6,is = 3065.6 kJ/kg Dhis, TV AP = 265.4 kJ/kg Dh TV AP = 233.6 kJ/kg h6 = 3097.4 kJ/kg h7 = 3363.3 kJ/kg Teva = 250.4 °C hls (peva) = 1087.4 kJ/kg h3 = hls - cp*DTsc = 1063.2 kJ/kg DTpp = 10 °C Tc = 260.4 °C Qfumi a-c = 26360.7 kW Qeva+sh+rh = 26228.9 kW h5 - h3 = 2267.8 kJ/kg h7 - h6 = 265.9 kJ/kg m vap = 10.35 kg/s b) s7 = 7.395 kJ/kgK p8 = p9 = 2.70 bar T9 = Tsat(p9) = 130.0 °C h8,is = 2882.0 kJ/kg Dhis, TV MP = 481.3 kJ/kg Dh TV MP = 433.2 kJ/kg h8 = 2930.1 kJ/kg h9 = hls(p9) = 546.2 kJ/kg s8 = 7.493 kJ/kgK h10,is = 2726.5 kJ/kg Dhis, TV LP = 203.7 kJ/kg Dh TV LP = 177.2 kJ/kg h10 = 2753.0 kJ/kg Tsat p11 = 99.61 °C hliq sat at p11 = 417.4 kJ/kg h1 = 377.09 kJ/kg c) Qeco = 7102.9 kW Qfumi c-d = 7138.6 kW Td = 195.5 °C a b c e d 1 2 3 4 5 8 10 9 G E A BC D F 11 6 7 Qfumi d-e = 10500.7 kW Qacqua B-C = 10448.2 kW mB = 62.2 kg/s d) sistema di 3 equazioni con 3 variabili (m8, m10, mD): m8*(h8 - h1) + m10*(h10 - h1) = mD*cpw*(TF - TA) m8*(h8 - h9) = mD*cpw*(TF - TE) mvap = m8 + m10 --> mD*cpw*(TF - TE) / (h8 - h9) * (h8 - h1) + mvap*(h10 - h1) - mD*cpw*(TF - TE) / (h8 - h9) * (h10 - h1) = mD*cpw*(TF - TA) --> mD = mvap*(h10 - h1) / [cpw*(TF - TA) + cpw*(TF - TE) / (h8 - h9) * (h10 - h1) - cpw*(TF - TE) / (h8 - h9) * (h8 - h1) ] mD = 152.1 kg/s m8 = 5.36 kg/s m10 = 4.99 kg/s e)…