The Second Virial Coefficient of Ordinary Water Substance: A New Correlation

Abstract

It is shown that the specific second virial coefficient for ordinary water substance, expressed as a function of temperature, is correlated by This correlation, motivated by recent observations from low-pressure steady-flow calorimetry from 20°C to 140°C, also covers older tabulated values of the second virial coefficient extending to 800°C. The Boyle temperature is found to be 1498 K. B 2 = a 1 f 1 + a 2 f 2 + a 3 f 3 where f 1 = 1/(1 + T/α), f 2 = (1 - e -β/ T ) 5/2 ( T/β) 1/2 e β/ T , f 3 = β/ T, α = 10000 K, β = 1500 K, a 1 = 0.0015 m 3 /kg, a 2 = −0.000942 m 3 /kg and a 3 = −0.0004882 m 3 /kg.