I'm working on a dewpoint algorithm for the Peng-Robinson equation in Mathcad and currently have the solver working (more or less) OK for a binary mix - I'd like to extend to a ternary or quaternary mix. Has anybody seen a good (ie copes with supercritical compenents, stable etc) implementation of such an algorithm?
Have you consulted the book "The Properties of Gases & Liquids" by Reid, Prausnitz, and Poling 4th Edition McGrawHill Book Co. Chapter 3 Section 6? It extends the Peng Robinson Equation to multi components.
This is probably a year too late.... but anyhow... If you go to the John Wiley & Sons, publishers website for my book "Chemical and Engineering Thermodynamics", 3rd edition, and then go to the area where you can download programs, you will find dew point, bubble point and isothermal flash MATHCAD worksheets for the Peng-Robinson EoS that can be used with any number of components. S. I. Sandler
Would you care to post those Mathcad sheets here. I have been trying to develop Mathcad sheets and Excel spreadsheets to use chemical and petroleum properties to do Flash calculations. Process Simulators are so expensive. Simple flash calculations by hand are a pain. I don't know how our forebearers did it. Those old Chemical Engineers must have had a lot of patience!