/** This is an attempt to use the water.frink libraries to obtain a high-accuracy boiling point of water at a specific ambient atmospheric pressure. It is primarily based on The International Association for the Properties of Water and Steam (IAPWS, http://iapws.org/ ) document IAPWS R6-95(2018), a PDF of which is usually available from: http://www.iapws.org/relguide/IAPWS-95.html Specifically, the file http://www.iapws.org/relguide/IAPWS95-2018.pdf */ use water.frink use secant.frink ambientPressure = 1 atm println["Ambient pressure = " + format[ambientPressure, "atm", 6]] Torig = Water.approxSaturatedTemperature[ambientPressure] println["Original temperature guess = " + format[C[Torig], 1, 6] + " C"] rhoL = Water.approxSaturatedLiquidDensity[Torig] println["Original liquid density guess = " + format[rhoL, "g/cm^3", 6]] rhoV = Water.approxSaturatedVaporDensity[Torig] println["Original vapor density guess = " + format[rhoV, "g/cm^3", 6]] T = Torig T1 = T * 1.000001 /* This next bit is trying to apply the phase-equilibrium condition (Maxwell criterion) to solve for the unknowns. See top of p. 12 in IAPWS-95 */ deltaV = rhoV / Water.rhoc tau = Water.Tc / T psigmaV = Water.R T rhoV (1 + deltaV Water.dphirdeltaDimensioned[rhoV, T]) println["psigmaV = " + format[psigmaV, "atm", 6]] deltaL = rhoL / Water.rhoc tau = Water.Tc / T psigmaL = Water.R T rhoL (1 + deltaL Water.dphirdeltaDimensioned[rhoL, T]) println["psigmaL = " + format[psigmaL, "atm", 6]]