Taylor Series for Peng-Robinson Equilibrium Properties Using Similarity Variables Conference: AIChE Annual MeetingYear: 2017Proceeding: 2017 AIChE Annual MeetingGroup: Student Poster SessionsSession: Undergraduate Student Poster Session: Computing and Process Control Time: Monday, October 30, 2017 - 10:00am-12:30pm The Peng-Robinson (PR) equation of state (EoS) is used to determine vapor pressure in addition to PVT properties. In this work, a dimensionless version of the PR equation has been simplified by combining the temperature and acentric factor into a similarity variable, Î·, termed the adjusted temperature. Other new dimensionless variables were defined by combining pressure and temperature into a dependent variable, Î¨, termed the adjusted pressure, and by defining a reduced density variable, Ïr', relative to the maximum liquid density in the low temperature limit. A Taylor series expansion in the similarity variable Î· was used to express reduced phase densities and vapor pressure by simple polynomials. The truncation error of these series was characterized. This work resulted in a simpler method of estimating PVT properties and vapor pressure that would be predicted by the PR equation for any substance.