An Improved Representative Equation for the Dynamic Viscosity of Water Substance

Abstract

Experimental evidence for steam and other fluids has demonstrated the existence of an anomalous enhancement of the dynamic viscosity in the close vicinity of the critical point. A re-analysis of the experimental evidence for the viscosity of steam indicates that the observed behavior of the critical viscosity enhancement is consistent with current theoretical predictions. An interpolating equation for the dynamic viscosity of water substance is presented which is in good agreement with the experimental viscosity data in a large range of temperatures and pressures. The equation contains a smaller number of coefficients than the current international equation for the viscosity of water substance and incorporates the enhancement of the viscosity in the close vicinity of the critical point.