3 replies to this topic

Hello,
I am using DDBSP to calculate the dew point and bubble point of a sample mixture. This software allows to choose one of their three methods to calculate: Predictive Soave-Redlich-Kwong, modified Predictive Soave-Redlich-Kwong and Volume-Translated Peng-Robinson equations.
My problem is that I dont know which method will give the most reliable result for the mixture I interested in. Is there any strategy to determine which method is best fit for a particular type of sample mixture ?
Your reply is much appreciated,
Thank you

[Zauberberg]

Basically, all three EOS should give results that are very close to each other, especially if there are no pseudocomponents present in the mixture. Improvements to original Peng-Robinson or SRK model are being incorporated almost on a monthly basis, targeting for more accurate property predictions - liquid densities, 2 liquid phase regions etc. Whichever model you choose, bubble/dew-point calculation should be very consistent, as long as you are far away from critical and supercritical conditions.

Thank you very much, Zauberberg
I remember that once I read some types of chart ( I forgot the name) that can be used to determine which type of calculation model ( UNIQAC, UNIFAC, EoS, etc ...) is best matched for a particular system. Do you what it is?
Thanks again

[Zauberberg]

There's one document at Clarkson University web page: http://people.clarks...gn/TherModl.pdf

Regards,