lemmon_2000

E. W. Lemmon, R. T Jacobsen, S. G. Penoncello and D. G. Friend, “Thermodynamic Properties of Air and Mixtures of Nitrogen, Argon, and Oxygen From 60 to 2000 K at Pressures to 2000 MPa”, J. Phys. Chem. Ref. Data 29, 331 (2000)

Source record · Catalogue · Review register

DOI: 10.1063/1.1285884

Source kind: fit

Recorded technique: Fit: a pseudo-pure-fluid Helmholtz equation of state for dry air (§4), and a mixture model for N2, Ar and O2 (§5) with linear-plus-quadratic reducing functions and one generalized departure function scaled per pair, both fitted to p-rho-T, caloric, sound-speed and phase-equilibrium data of air and the binaries.

Materials in structured entries: None recorded.

Dataset quantities: None recorded.

Contents: 0 datasets; 0 formulas.

Curation notes

Identity VALIDATED_WITH_WARNINGS by the library. Printed page = pdf page + 330 (checked on the rendered pages, 2026-09-30). The library’s text renders minus signs in Tables 7, 13 and 15 as ‘2’ (Table 7’s ‘20.219’ is -0.219 dm^3/mol), ‘310^’ for x10^, ‘~ !’ for parentheses and ‘61’ for +-1, and merges Table 8’s Ar-O2 rows; the numbers below were read from the pages.

THE PSEUDO-PURE AIR EQUATION (§4, Eqs. 25-26, Table 13, p. 346): the equation CoolProp uses for ‘Air’ (reference key Lemmon-JPCRD-2000), the density of OEP 1’s Gas.Air. Composition: Jones (1978), normalised without CO2, N2 0.7812, O2 0.2096, Ar 0.0092 (Table 3, p. 337; with CO2, Table 2: 0.7810, 0.2095, 0.0092, 0.0003). Range about 59.75-2000 K to 2000 MPa (abstract, p. 331). Uncertainty 0.1 % in density (k = 2) from the solidification point to 873 K up to 70 MPa (§7.2, p. 360).

THE MIXTURE MODEL (§5, pp. 349-350, Eqs. 61-69): a = a_idmix + a^E; 1/rho_red = sum x_i/rho_ci + sum sum x_i x_j xi_ij, T_red = sum x_i T_ci + sum sum x_i x_j zeta_ij (not the GERG form); alpha^E = (sum sum x_i x_j F_ij) [-0.00195245 delta^2 tau^-1.4 + 0.00871334 delta^2 tau^1.5] (Eq. 63). Table 15 (p. 350): N2-Ar F 1.121527, zeta -1.237713 K, xi -0.00076031 dm^3/mol; N2-O2 F 1, zeta -0.856350, xi -0.00041847; Ar-O2 F 0.597203, zeta -2.115126, xi +0.00041232. Fitted to Crain and Sonntag, Palavra, and Kosov and Brovanov (N2-Ar) and to Pool et al. 1962 with air and VLE data (N2-O2, Ar-O2; the air data had the ‘largest impact’ on N2-O2) (p. 340). Valid to 1000 K and 100 MPa; within 0.1 % in density for the binaries and ternaries (p. 360), verified ranges in Table 17: N2-Ar 70-420 K to 800 MPa; N2-O2 and air 60-870 K to 100 MPa; Ar-O2 only 70-90 K to 0.2 MPa (its p-rho-T data, p. 355), unverified at 70-400 K with at least 0.5 %. This is not the mixture model CoolProp uses for N2-O2-Ar (its pairs are Gernert’s and GERG-2008’s). Against air p-rho-T data the pseudo-pure and mixture models both have an overall AAD of 0.097 % (Table 6, p. 339); near ambient, Michels 1954a 0.022 against 0.030 %, Kozlov 0.072 against 0.069 %.

SECOND VIRIAL: of air only (Table 6, p. 339; Michels et al. 1954 fitted, Romberg’s re-derived values in Table 7, p. 340); no cross second virial coefficients of the pairs. ‘The second virial coefficients calculated from the mixture model are not as accurate’ as the air equation’s (p. 355), from the O2 equation’s low-temperature behaviour; the O2 equation is valid only to 300 K and 82 MPa, its extrapolation to 1000 K checked to 0.5 % (p. 360). Nothing transcribed.

Recorded bibliographic identity status: VALIDATED_WITH_WARNINGS. This concerns identification of the source; it does not establish the scientific correctness of its contents.

Datasets

No datasets are recorded.

Formulas

No formulas are recorded.

Corrections

No dataset errata are recorded in this source record.

Formula corrections, where recorded, appear with their formulas above. Curation notes may also discuss corrections or unresolved interpretation. Consult the review register for the checks and decisions.