The Viscosity of Superheated Steam up to 275 Deg C: A Refined Determination

Abstract

This paper describes a series of measurements made with an oscillating disk viscometer of the viscosity of superheated steam. These measurements were made on eight isotherms, ranging from 148 deg C to 275 deg C, and thus go to a temperature higher than previously achieved with steam in this type of instrument. The measurements again show that in the range of temperature investigated the viscosity of superheated steam decreases with increasing density. The precision of the present measurements has permitted a simple correlation to be made of the effect of temperature and density upon the viscosity. From this it now appears that the temperature at which the density effect ceases to be negative is about 315 deg C. The correlation of the present results is μμpoise=88.020+0.32827tdegC+0.00021350t2(degC)2−−ρg/cm31858−5.90tdegC The standard deviation of the measurements from this is 0.26 μpoise.