The Huron-Vidal HVO Model

Vidal (1978) and later Huron and Vidal (1979) proposed the first successful combination of an EOS and activity coefficient models by requiring that the mixture EOS at liquid densities should behave like an activity coefficient model. To ensure a liquid density at all temperatures, this equality was made using eqn. (4.1.7) and the relation 

That is, to keep G qs finite in order to use eqn. (4.1.7), eqn. (4.2.2) must also be used. Equations (4.1.7 and 4.2.2) provide the two equations necessary to determine the two EOS constants. The resulting mixing rule for the a parameter is 

Some results obtained with the HVO mixing rule are presented in the following paragraphs. These results were obtained with the computer program HV provided on the accompanying diskette the computational details are presented in Section D.4 of Appendix D. 

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