Hope College Engineering Department
Research Experiences for Undergraduates
Summer 2008
Project Summary

 

Project Title: Generalized Vapor Pressure Prediction Consistent with Cubic Equations of State
Student Name: Laura Petrasky
Student's Home Institution: Hope College
Research Advisor: Dr. Michael Misovich
Source of Support: This material is based upon work supported by the Hope College Dean for the Natural and Applied Sciences Office and the Michigan Space Grant Consortium.

Chemical engineers can predict vapor pressures using cubic equations of state (EOS), power series, or the Antoine equation. Cubic EOS predict vapor pressure over a wide temperature range; however, they require complex numerical algorithms.  Power series express vapor pressure explicitly in temperature, but many terms are needed to minimize truncation error.  The Antoine equation is the simplest method, but it requires substance specific constants and is only valid over limited temperature ranges.  A continuous least squares statistical method was used to transform a power series vapor pressure expression to a dimensionless, generalized variant of the Antoine equation.  The dimensionless constants depended upon the substance-specific acentric factor.  After a simultaneous slope and average correction was applied, vapor pressure estimates within 0.1 percent of the commonly used Soave-Redlich-Kwong EOS were produced for reduced temperatures between 0.6 and 1.0.

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Publications and Presentations:
Petrasky, L.L. and Misovich, M.J., "Generalized Vapor Pressur Prediction Consistent with Cubic Equations of State", AIChE Ann. Mtg. CD-ROM Proc. (2008). Conference presentations: Students Participate in Chemical Engineering Conference, November 14-17, 2008

Petrasky, L.L. and Misovich, M.J., "Generalized Vapor Pressur Prediction Consistent with Cubic Equations of State", Thirteenth Annual Michigan Space Grant Consortium Conference, University of Michigan, Ann Arbor, MI (2008).