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Contribute to whitson wiki

The whitson wiki is a living document that aims to give a good overview of topics related to PVT and phase behavior. This task is not an easy one and therefore need to constantly update the content as a collective unit. If you want to contribute in a small or large degree we thank you.

Generic text for un-finished pages: "Article is not written yet. If you want to contribute, please follow the intructions in the Contribute section."

To contribute contact Markus Hays Nielsen via mail with (1) the page that you want to contribute to (e.g., (2) a description of the section that you want to modify (e.g. "API Specific Gravity" or from "some text" to "some other text") and (3) a desription of what you want to change (e.g. spelling mistake: change the word "wrk" to "work" | re-write paragraph to make more clear | developed unfinished page, see attached file).

The four tiers of contribution are (1) small fixes (e.g. spelling mistakes, sentence re-structuring, etc.), (2) modifying a paragrah or multiple paragraphs entirely, (3) writing an entirely new page and (4) structure suggestions to website or nomenclature (more cumbersome changes that require collaboration with the wiki software team). More details about how to contribute to the different tiers is given below.

Small Fixes

An example of the procedure for reporting small fixes to the text is given below:


Current Text: A correction factor to the mixing term for a cubic EOS.

Relace With: A correction term kij for component pair i-j used in the “a” parameter mixing rule of a cubic EOS. kij=0 indicates no correction. A maximum range is usually kij≈-0.1 to +0.2 for hydrocarbon-hydrocarbon pairs, kij≈+0.05 to +0.15 for hydrocarbon/non-hydrocarbon pairs (e.g. N2, CO2, H2S). BIPs are symmetric kij=kji, and kii=0. The BIP kij usually has a strong impact on K-values Ki and Kj, but may impact the K-values of all components. BIPs can be temperature dependent. Binary interaction coefficient (BIC) is sometimes used instead of BIP.

Fix Type: Spelling mistake / sentence strukture re-work / missing word / etc.

Paragraph-Level Changes

An example of the procedure for reporting paragraph-level changes to the text is given below:


From Text: "An equation of state is a function that relates the properties pressure..."

To Text: "A tuned EOS model can be a valuable tool for many reservoir and process engineering tasks"

Replace With: "Some other text to replace"

Reasons: The way it is written now is not clear / not correct / hard to understand / very dry so I added figures.

Writing a New Page

Make a draft page in Word, Latex, Text file or MarkDown and send it to Markus Hays Nielsen together with (1) a short description of the topic and (2) if there is no page on the curent topic, please recommend a place in the folder structure of the wiki. Please remember to mark any potential hyperlinks (e.g. there is a section on the bubble point, so the first mention of the bubble point in a new article should link to this page url). If you are writing in Word it is possible to add the hyperling to the relevant word or words. If you are writing in a text file or markdown please indicate the url by something like: some hyperlink text (

Web-Page Structure and Nomenclature Changes

Contact Markus Hays Nielsen with a short description of the issue and ask to set up a meeting to discuss in more detail.