Fundamental Constants
Vapor Pressure
Latet Heat
Saturated Densities

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Comparing Saturated Densities

Comparisons of the saturated liquid densitiy, from the triple point to the critical point is summarized below:

Relative Error (Liquid Density)	IAPWS-IF97	NBS/NRC-84	IFC-67
Maximum absolute error	2.293%	7.931%	10.907%
Average absolute error	0.123%	0.196%	0.204%
Root Mean Square error	0.407%	0.828%	1.092%

Comparisons of the saturated vapor densitiy, from the triple point to the critical point is summarized below:

Relative Error (Vapor Density)	IAPWS-IF97	NBS/NRC-84	IFC-67
Maximum absolute error	2.666%	8.000%	11.862%
Average absolute error	0.141%	0.315%	0.341%
Root Mean Square error	0.471%	0.955%	1.276%

Note: The IAPWS-95 formulation is used as the baseline for comparisons.

A chart of the deviations is available in PDF format. Also, the Excel spreadsheet used to generate this summary and chart is also available:

Comparing saturated liquid density (PDF file)

(9 KB; compare_sat_liq_density.pdf; January 22, 1999)

Comparint saturated vapor density (PDS Format Chart)

(13 KB; comapre_sat_vap_density.pdf; January 22, 1999)

Comparing saturated liquid density (Excel file)

(93 KB; compare_sat_liq_density.xls; January 22, 1999)

Comparing saturated vapor density (Excel file)

(93 KB; compare_sat_vap_density.xls; January 22, 1999)