Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Problem with specific heat at constant pressure value for heavy water #32

Closed
khurrumsaleem opened this issue Jul 17, 2018 · 5 comments
Closed

Comments

@khurrumsaleem
Copy link

Hi!

First of all, I would like to thank you very much for your awesome effort of maintaining this repository. Secondly, I think there is some problem with specific heat at constant pressure value for heavy water. I was checking it against the steam table by Hill (http://www.iaea.org/inis/collection/NCLCollectionStore/_Public/14/730/14730979.pdf?r=1) and its values are good upto 6 MPa but after that at 8 MPa pressure and 290 Celsius, it gives a value of 2.784817 although the value quoted in document is 5.218.

Thanks once again and looking forward to your feedback.

@jjgomera
Copy link
Owner

Hi,
I get the correct value:

>>> from iapws import D2O
>>> D2O(T=290+273.15, P=8).cp
5.20603115473

Check your code, be careful with units (temperature in Kelvin, pressure in MPa). Furthermore the new standard for heavy water changed in 2017: http://iapws.org/relguide/Heavy.html, so the tables from Hill and outdated.

Thanks for feedback

@khurrumsaleem
Copy link
Author

@jjgomera thank you very much for your response. Please take a look at the screenshot. I am exactly writing the same thing but I am still getting the incorrect answer

image

Can you suggest what might be the problem at my end?

@jjgomera
Copy link
Owner

Ummm, are you using the last version?

@khurrumsaleem
Copy link
Author

khurrumsaleem commented Jul 21, 2018

after getting the erroneous value, I downloaded and installed the latest version but no betterment in results for my case.

@khurrumsaleem
Copy link
Author

khurrumsaleem commented Jul 22, 2018

@jjgomera I reinstalled by deleting the earlier installation and it works fine now. Thank you very much for all the help.

You can go ahead and close the issue now so as not to clutter the repository with non-existent issues.

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Labels
None yet
Projects
None yet
Development

No branches or pull requests

2 participants