Equations of State part 6: solving Peng-Robinson cubic roots

Screencast showing how to solve the cubic roots for the Peng-Robinson equation of state, including calculations, a plot of pressure versus molar volume and the prediction of vapour-liquid coexistence.
Presented by Dr Daniel Belton, University Teaching Fellow, University of Huddersfield.
The spreadsheet used in this video can be downloaded at: drive.google.c...

[@rlhugh]

How do you calculate the saturated vapor pressure?

[@leventali5491]

Thank you very much. Sir. All your videos are extremely useful in process engineering area.

[@omarbensalem5558]

Thank you very muche sir. Is there any video regarding the steps for tuning EOS

[@matthewjeradechetty3996]

Great help, but one question. When solving for the emperical function 'alpha'. The correct equation is: (1+(0.37464+1.54226w-0.26992w^2)(1-sqrt(Tc))^2. However, in your excel work. You multiplied this value by the Critical temperature again, why is this so? Any clarification would be greatly appreciated. Thanks

[@minjinseo3681]

How to get value of T in order to solve Tr in formula Tr = T/Tc?

[@bitanchowdhury4028]

Sir, can we use this excel in case when only one real root and two imaginary root appear or single phase case? Will it give the result ?

[@ismailbarrera6495]

Hello, For problems like this, are we supposed to calculate critical pressure and temperature? Thank you!

[@ChemEngTutor]

No, you can look them up in a book or online.

[@Boyka-1234]

Buenas tardes, podría explicar por favor los coeficientes de fugacidad y como es que se hace la iteracion de K

[@shutter.snitch]

I checked the cube function in excell. but could not find. Should we set it up?

[@ChemEngTutor]

It is a custom function, as described the video. If you want to use it, you will need to download the spreadsheet using the link in the video description.

[@brunomiguel518]

Hello, thank for your video. Do you know how can i get the funtion "CUBIC"? thank you a lot.

[@ChemEngTutor]

Hi Bruno, it is a user defined/custom function written in VBA. If you download the file linked from the video description, this spreadsheet has a copy of the CUBIC function included in the background VBA code. I hope this helps. Thanks, ChemEngTutor

[@ChemEngTutor]

@Jacob Broitman Go to the “Developer” tab and click on “Visual Basic”. Then click on “mQuartic” shown under the “Modules” heading in the “Project” window - the code for the CUBIC function is shown about half way down. Does this help? If you cannot see the “Developer” tab, then you will need to make it visible - see support.microsoft.com/en-us/office/show-the-developer-tab-e1192344-5e56-4d45-931b-e5fd9bea2d45

[@craniumkracked8189]

Can we solve this on solver ?

[@amindarvishi6147]

can you share excel code for "cubic" solve equation?

[@InfinityLRDL]

How did you solve the Cubic Equation?

[@ChemEngTutor]

I used the CUBIC custom VBA function as described in the video.

[@InfinityLRDL]

ChemEngTutor do you have a video where you teach how to use VBA? Im a little confused on how to use it

[@particleonazock2246]

penguinson equation