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Viscosity of Ordinary Water Substance Calculation

based on equations for industrial use

Developed by Russian National Committee (RNC) of

International Association for the Properties of Water and Steam (IAPWS).

This calculation page is based on the

"Release on the IAPWS Formulation 2008 for the Viscosity of Ordinary Water Substance" [1]

provided by IAPWS.

Detailed information about used equations, constants, range of validity etc is presented in PDF version of IAPWS Release which can be downloaded from IAPWS web site www.iapws.org

Authors (and responsible persons):

Moscow Power Engineering Institute (MPEI). Last update: 2012/09/21

Note that displayed last digits depends on numeric implementation of underlying formulations.

Input parameters

Density for given pressure and temperature

Density value and other thermodynamic properties and derivatives are calculated using RNC implementation of [2].

Formulation reference values

Dimensionless input parameters

Main equation

The viscosity is represented by the equation

Eq. (10) in [1]

First factor

This factor represents the viscosity in the dilute-gas limit.

Coefficients from Table 1 [1] (can be downloaded here in text format):

Eq. (11) in [1]

Second factor

The second factor represents the contribution to viscosity due to finite density.

Coefficients from Table 2 [1] (can be downloaded here in text format):

Eq. (12) in [1]

Critical enhancement

For industrial uses where greater computing speed is needed, Eq. (10) should be simplified by setting critical enhancement equal to 1.

Results

relative viscosity:

viscosity:

References

1. Release on the IAPWS Formulation 2008 for the Viscosity of Ordinary Water Substance. Berlin, Germany September 2008, available at http://www.iapws.org

2. IAPWS, Revised Release on the IAPWS Industrial Formulation 1997 for the Thermodynamic Properties of

Water and Steam, available at http://www.iapws.org (2007).