.FCSys.Species.H2O.Gas.Fixed

Fixed properties

Information

Assumptions:

  1. The generalized resistivities (η, θ) are fixed (e.g., independent of thermodynamic state).
  2. Ideal gas
  3. The specific exchange currents (τ′) are zero. The rate of phase change is governed by the other configurations (liquid and ionomer).

The default resistivities (η = 1/(9.09e-6*U.Pa*U.s) and θ = U.m*U.K/(19.6e-3*U.W)) are of H2O gas at saturation pressure and 300 K from Incropera and DeWitt [Incropera2002, p. 921]. Table 1 lists the properties at saturation pressure and other temperatures. Table 2 lists the properties of H2O gas at 1 atm. See also http://www.engineeringtoolbox.com/water-dynamic-kinematic-viscosity-d_596.html.

Table 1: Properties of H2O gas at saturation pressure [Incropera2002, pp. 924–925].
T
/U.K		 cp*U.kg*U.K
/(U.J*Data.m)		 η
*U.Pa*U.s		 θ*U.W
/(U.m*U.K)
273.15 1854 1/8.02e-6 1/18.2e-3
275 1855 1/8.09e-6 1/18.3e-3
280 1858 1/8.29e-6 1/18.6e-3
285 1861 1/8.49e-6 1/18.9e-3
290 1864 1/8.69e-6 1/19.3e-3
295 1868 1/8.89e-6 1/19.5e-3
300 1872 1/9.09e-6 1/19.6e-3
305 1877 1/9.29e-6 1/20.1e-3
310 1882 1/9.49e-6 1/20.4e-3
315 1888 1/9.69e-6 1/20.7e-3
320 1895 1/9.89e-6 1/21.0e-3
325 1903 1/10.09e-6 1/21.3e-3
330 1911 1/10.29e-6 1/21.7e-3
335 1920 1/10.49e-6 1/22.0e-3
340 1930 1/10.69e-6 1/22.3e-3
345 1941 1/10.89e-6 1/22.6e-3
350 1954 1/11.09e-6 1/23.0e-3
355 1968 1/11.29e-6 1/23.3e-3
360 1983 1/11.49e-6 1/23.7e-3
365 1999 1/11.69e-6 1/24.1e-3
370 2017 1/11.89e-6 1/24.5e-3
373.15 2029 1/12.02e-6 1/24.8e-3
375 2036 1/12.09e-6 1/24.9e-3
380 2057 1/12.29e-6 1/25.4e-3
385 2080 1/12.49e-6 1/25.8e-3
390 2104 1/12.69e-6 1/26.3e-3
400 2158 1/13.05e-6 1/27.2e-3
410 2221 1/13.42e-6 1/28.2e-3
420 2291 1/13.79e-6 1/29.8e-3
430 2369 1/14.14e-6 1/30.4e-3
440 2460 1/14.50e-6 1/31.7e-3
450 2560 1/14.85e-6 1/33.1e-3
460 2680 1/15.19e-6 1/34.6e-3
470 2790 1/15.54e-6 1/36.3e-3
480 2940 1/15.88e-6 1/38.1e-3
490 3100 1/16.23e-6 1/40.1e-3
500 3270 1/16.59e-6 1/42.3e-3
510 3470 1/16.95e-6 1/44.7e-3
520 3700 1/17.33e-6 1/47.5e-3
530 3960 1/17.72e-6 1/50.6e-3
540 4270 1/18.1e-6 1/54.0e-3
550 4640 1/18.6e-6 1/58.3e-3
560 5090 1/19.1e-6 1/63.7e-3
570 5670 1/19.7e-6 1/76.7e-3
580 6400 1/20.4e-6 1/76.7e-3
590 7350 1/21.5e-6 1/84.1e-3
600 8750 1/22.7e-6 1/92.9e-3
610 11100 1/24.1e-6 1/103e-3
620 15400 1/25.9e-6 1/114e-3
635 18300 1/27.0e-6 1/121e-3
630 22100 1/28.0e-6 1/130e-3
635 27600 1/30.0e-6 1/141e-3
640 42000 1/32.0e-6 1/155e-3

Table 2: Properties of H2O gas at 1 atm [Incropera2002, p. 921].
T
/U.K		 cp*U.kg*U.K
/(U.J*Data.m)		 η
*U.Pa*U.s		 θ*U.W
/(U.m*U.K)
380 2.060e3 1/127.1e-7 1/24.6e-3
400 2.014e3 1/134.4e-7 1/26.1e-3
450 1.980e3 1/152.5e-7 1/29.9e-3
500 1.985e3 1/170.4e-7 1/33.9e-3
550 1.997e3 1/188.4e-7 1/37.9e-3
600 2.206e3 1/206.7e-7 1/42.2e-3
650 2.056e3 1/224.7e-7 1/46.4e-3
700 2.085e3 1/242.6e-7 1/50.5e-3
750 2.119e3 1/260.4e-7 1/54.9e-3
800 2.152e3 1/278.6e-7 1/59.2e-3
850 2.186e3 1/296.9e-7 1/63.7e-3

The specific heat capacity is not fixed because it would affect the chemical potential and result in an incorrect cell potential.

The relative humidities (RH and RHboundaries), which are calculated as output variables, do not account for surface tension.

For more information, please see the Species model.

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