%The following data is extracted from Table A-4 of Cengel and Turner, %"Fundamentals of Thermal-Fluid Sciences", McGraw-Hill 2001. %I want to make a phase diagram in the PV plane for water with it. %Ted Golfinopoulos, 5.16/2008 %The data is organized as temperature (degrees Celsius), pressure (kPa), saturated liquid %specific volume (m^3/kg), saturated vapor specific volume (m^3/kg). T=[0.01 5:5:320 330:10:370 374.14]'; vg= [ 206.14 147.12 106.38 77.93 57.79 43.36 32.89 25.22 19.52 15.26 12.03 9.568 7.671 6.197 5.042 4.131 3.407 2.828 2.361 1.982 1.6729 1.4194 1.2102 1.0366 0.8919 0.7706 0.6685 0.5822 0.5089 0.4463 0.3928 0.3468 0.3071 0.2727 0.2428 0.2168 0.19405 0.17409 0.15654 0.14105 0.12436 0.11521 0.10441 0.09479 0.08619 0.07849 0.07158 0.06537 0.05976 0.05471 0.05013 0.04598 0.04221 0.03877 0.03564 0.03279 0.03017 0.02777 0.02557 0.02354 0.02167 0.019948 0.018350 0.016867 0.015488 0.012996 0.010797 0.008813 0.006945 0.004925 0.003155]; vf=[ 0.001 0.001 0.001 0.001001 0.001002 0.001003 0.001004 0.001006 0.001008 0.001010 0.001012 0.001015 0.001017 0.001020 0.001023 0.001026 0.001029 0.001033 0.001036 0.001040 0.001044 0.001048 0.001052 0.001056 0.001060 0.001065 0.001070 0.001075 0.001080 0.001085 0.001091 0.001096 0.001102 0.001108 0.001114 0.001121 0.001127 0.001134 0.001141 0.001149 0.001157 0.001164 0.001173 0.001181 0.001190 0.001199 0.001209 0.001219 0.001229 0.001240 0.001251 0.001263 0.001276 0.001289 0.001302 0.001317 0.001332 0.001348 0.001366 0.001384 0.001404 0.001425 0.001447 0.001472 0.001499 0.001561 0.001638 0.001740 0.001893 0.002213 0.003155]; P=[0.6113 0.8721 1.2276 1.7051 2.339 3.169 4.246 5.628 7.384 9.593 12.349 15.758 19.940 25.03 31.19 38.58 47.39 57.83 70.14 84.55 101.33 120.82 143.27 169.03 198.53 232.1 270.1 313.0 361.3 415.4 475.8 543.1 617.8 700.5 791.7 892.0 1002.1 1122.7 1254.4 1397.8 1553.9 1723.0 1906.2 2104 2318 2548 2795 3060 3344 3648 3973 4319 4688 5081 5499 5942 6412 6909 7436 7993 8581 9202 9856 10547 11274 12845 14586 16513 18651 21030 22090]; %Superheated water isotherms: Ts=[350; ]; Piso=[500, 600, 800, 1000, 1200, 1400 1600 1800 2000 2500 3000 3500 4000 4500 5000 6000 7000 8000 9000 10000 12500 15000 20000];% 30000 50000]; %For T=200: [21.825, 4.356,, 2.172, 1.0803, 0.7163, 0.5342, 0.4249, 0.3520, 0.2608, %0.2060, 0.1693, 14302;... v350=[0.5701 0.4742 0.3544 0.2825 0.2345 0.2003 0.17456 0.15457 0.13857 0.10976 0.09053 0.07678 0.06645 0.05840 0.05194 0.04223 0.03524 0.02995 0.02580 0.02242 0.016123 0.011470 (0.0015684+0.0018226)*0.5];% (0.0014920+0.0016265)*0.5 (0.0014032+0.0014838)*0.5]; v400=[0.6173 0.5137 0.3843 0.3066 0.2548 0.2178 0.19005 0.16847 0.15120 0.12010 0.09936 0.08453 0.07341 0.06475 0.05781 0.04739 0.03993 0.03432 0.02993 0.02641 0.02000 0.015649 0.009942];% 0.002790 0.0017309 ]; Pcrit=[Piso 25000 30000 35000 40000 50000 60000]; vcrit=[(v350+v400)/2 0.0019731 0.0017892 0.0017003 0.0016407 0.0015594 0.0015028]; %Psuper=linspace(min(Piso), max(Piso), 50); vsuper=v350(1:length(v350)-1);%logspace(min(vcrit), max(vcrit), 50); %van der Waals isotherm parameters for water from Wikipedia, %http://en.wikipedia.org/wiki/Van_der_Waals_constants_%28data_page%29 kg2mol=1000/18; mol2kg=1/kg2mol; a=5.536/(mol2kg^2)/10; b=0.03049/1000; kB=1.3806504E-23; Na=6.02E23; Ts=450+273; p=Na*kB*Ts./(vsuper*mol2kg-b)-a.*(vsuper).^-2; p=p/1000; %Convert to kpa. %Psuper=fsolve(@(p) ( p+a*(vsuper.^(-2))).*(vsuper-b)-kB*Ts, Pcrit); xxf=logspace(log10(min(vf)), log10(max(vf)), 100)'; xxg=logspace(log10(min(vg)), log10(max(vg)), 100)'; cs=spline(vf(3:length(vf)), [P(3); P(3:length(P)); P(length(P))]); yyf=ppval(cs,xxf); cs=spline(vg, [P(1); P; P(length(P))]); yyg=ppval(cs,xxg); figure(1) clf(1) hold on %semilogx(xxf, yyf, 'k', xxg, yyg, 'k') semilogx(vf(3:length(vf)), P(3:length(P)), 'k', vg, P, 'k') semilogx(vcrit, Pcrit, 'r.')