25 06 20sol

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Data Values from tables/charts Data from person code Person code: 12345678 1 2 3 4 5 6 7 8 X 36 Y 260 Problem 1: psteam = 4 bar Tw,in = 25 °C Tg,in = 360 °C mg,in = 260 kg/s cp,g = 1.1 kJ/kgK DTmin = 10 °C a) hsat,steam = 2738 kJ/kg hsat,liq = 605 kJ/kg hw,in = 105 kJ/kg Tsat = 143.6 °C Tgas,out = 153.6 °C Qgas = 59027 kW m,steam = 22.42 kg/s b) U = 260 W/m2K Qeco = 11199 kW Tgas,eco,out = 320.8 °C DTeco1 = 335 °C DTeco2 = 177.2 °C LMTDeco = 247.8 K Aeco = 173.8 m2 DTeva1 = 177.2 °C DTeva2 = 10 °C LMTDeva = 58.2 K Qeva = 47828 kW Aeva = 3162 m2 Atot = 3336 m2 Problem 2: Tamb = 15 °C pamb = 1.013 bar cp = 1 kJ/kgK gamma = 1.4 TIT = 850 °C P = 260 kW beta = 7.2 eta,is = 0.80 Dp,filter = 1 % Dp,he = 4 % a) pc,in = 1.003 bar pc,out = 7.221 bar Tc,out,is = 506.5 K = 233.3 °C Tc,out = 287.9 °C Wc = 272.9 kJ/kg qin = 562.1 kJ/kg pt,in = 6.932 bar pt,out = 1.013 bar TOT,is = 648.3 K = 375.2 °C TOT = 470.1 °C W,turb = 379.9 kJ/kg Wnet = 106.9 kJ/kg eta = 19.02 % b) m,air = 2.43 kg/s c) m,air = 1.22 kg/s pt,in = 3.466 bar (chocked flow at turbine inlet) pt,out = 1.003 bar TOT,is = 788.06 K = 514.9 °C TOT = 581.9 °C pc,out = 3.610 bar pc,in = 1.003 bar Tc,out,is = 415.5 K = 142.3 °C Tc,out = 174.2 °C WC = 159.2 kJ/kg Wt = 268.1 kJ/kg Wnet = 108.9 kJ/kg qin = 675.8 kJ/kg eta = 16.11 % Wnet = 132.4 kW Problem 3: X 36 Y 260 fluid R134a water flow rate 36 kg/s Tin_water 10 °C Tout_water 85 °C Teva 18.7 °C superheating 0 °C X vap fract eva inlet 0.15 mass basis Tcond 90 °C isen eff comp 0.8 measure unit molar SI Solution h of sat liquid @ Teva 22997 J/mol 225 kJ/kg deltah evapor @ Teva 18731 J/mol 184 kJ/kg h of sat vapor @ Teva 41727 J/mol 409 kJ/kg molar mass R134a 102.03 kg/kmol h at eva inlet 25806.18 kJ/kg 253 kJ/kg h = x*hliqsat + (1-x)*hvapsat h at eva outlet 41727.37 kJ/kg 409…