Solution Entropy balance well insulated slow leak,reversible a-+0 0 =m2△s Air: △S=0 i.e.,S2=S1 P2 P2= Pri,p1=5bar,p2=1bar; T1=500K→p1=8.411(TabA-17) TABLE A-17 (Tab A-17) Ideal-gas properties of air T s P2=1.6822 ------>,T2=317K K kJ/kg P kJ/kg kJ/kg-K 310310.24 1.5546 221.25 572.3 1.73498 315315.27 1.6442 224.85 549.8 1.75106 320 320.29 1.7375 228.42 528.6 1.76690 325 325.31 1.8345 232.02 508.4 1.78249 330330.34 1.9352235.61 489.4 1.79783 m2 500K 490 492.74 7.824 352.08 179.7 2.19876 317K (5kg)=1.58kg 500 503.02 8.411 359.49 170.62.21952 510513.32 9.031 366.92 162.1 2.23993 520 523.63 9.684 374.36 154.12.25997 530 533.9810.37 381.84 146.72.27967 April 27,2018 9 SHANGHAI JIAO TONG UNIVERSITYApril 27, 2018 9 Solution Entropy balance well insulated slow leak, reversible i.e., s2=s Air: 1 , p1=5bar, p2=1bar; T1=500K  pr1=8.411 (Tab A-17) (Tab A-17)