Error in Cross_section file of U-235 and U-238 (1200K) of JEFF 3.2 and error of "No fission sites banked on processor"

User Support
1

Hello there,

I have JEFF 3.2 library file for 1200 K. When I used it in material firstly it has shown error of " could not find 12c file for U-235 and U-238 but 03c is available. I have checked U-235.ACE and U-238.ACE in ACEs_1200K folder. In first line of both file written as follow:

92238.03c 236.005800 1.0341E-07 02/21/14

92235.03c 233.024800 1.0341E-07 02/21/14

Then I have checked in ACEs_1800K folder for U-235 and U-238 same is written in first line.

92235.03c 233.024800 1.5511E-07 02/21/14

92238.03c 236.005800 1.5511E-07 02/21/14

I have found that the data following these lines are same as 300K ENDF data.

It showing temperature correctly as above and data is of 300K. So I have changed 92235.03c to 92235.12c in first line of ACE files for starting my simulation.

But I got error as follow.

Is this the reason why I found Error of “No fission sites banked on Processor 0”?

After this error I have tried to increase # of particles to 1 million still it giving same error.

Please tell me what to do because for other nuclides there are 12c in first line so no problem with them.

Thank you.

Regards
Darpan

2

Darpan,

If you changed the cross section identifier in the ACE file from 03c to 12c, you will also need to make a corresponding change in the cross_sections.xml file that you are using. As far as the error goes, that indicates that no fission occurred in the problem you ran. That could happen for a number of reasons so it’s hard to narrow it down based on the information you’ve given alone.

Paul

3

Hi Darpan,
It seems as if the JEF library you have is incorrectly organized. is this an official release?
Paul is right in that if you wanted to rename everything to be consistent, you will also have to update the cross_sections.xml file to match, just as you would have to do with the xsdir file in MCNP.

The no fission sites error is odd but makes sense if you have only a very small region of fuel in the problem - if you run a problem with more U-235 (similar to basic in the examples folder), would the same error be achieved?

4

I have changed the cross_sections.xml file correctly. I also found that it is reading correct ACE file for (1200 K or 300 K) for all material. Error is due to what I am not getting. I have changed the first line of 1200K file of 92235.12c to 92235.12c from 92235.03c Is this I think giving error?

5

I have downloaded from http://www.oecd-nea.org/dbforms/data/eva/evatapes/jeff_32/

I have increased the enrichment to 20 % for running program. Still it gives no fission site banked.

Still I am checking it again. things you both have mentioned.

6

Hi Darpan,
Can you post the cross_sections.xml file you are using that is causing this problem?
If that is too long, just the header (e.g:

`

<?xml version="1.0" ?>

<cross_sections>
/opt/xsdata/endf70
binary
<record_length>1024</record_length>
512

`
) and the lines specific to all the U-235 tempeatures.

Thanks!

7

Yes, here are some lines given in cross_sections_jeff.xml file I have downloaded the one uploaded by Mr. Paul Romano.

<cross_sections>
/home/darpan/Desktop/openmc/data/jeff/
ascii

<ace_table alias=“U-235.03c” awr=“233.025” location=“1” name=“92235.03c” path=“ACEs_300K/U235.ACE” temperature=“2.585e-08” zaid=“92235”/>

<ace_table alias=“U-235.03c” awr=“233.025” location=“1” name=“92235.03c” path=“ACEs_300K/U235.ACE” temperature=“2.585e-08” zaid=“92235”/>

<ace_table alias=“U-238.03c” awr=“236.0058” location=“1” name=“92238.03c” path=“ACEs_300K/U238.ACE” temperature=“2.585e-08” zaid=“92238”/>

<ace_table alias=“U-238.12c” awr=“236.0058” location=“1” name=“92238.12c” path=“ACEs_1200K/U238.ACE” temperature=“1.034e-07” zaid=“92238”/>

8

You dont have a U-235.12c entry in the cross_sections.xml file?

9

If this is true, simply change the second entry of U-235.03c to read as follows:

<ace_table alias="U-235.12c" awr="233.025" location="1" name="92235.12c" path="ACEs_1200K/U235.ACE" temperature="1.034e-07" zaid="92235"/>

Double-check the path to make sure its consistent with what it should be on your machine. That change should at least make OpenMC run when you tell it to use the 12c U-235 data.

I downloaded the JEFF 1200K data just now. The data does ship from the NEA with ACE headers that are inconsistent with both the provided xsdir file and the NJOY inputs (NJOY redirects to 12c). Darpan, once this is all done and you find if there are any other issues like this, it would probably be good to provide feedback to the NEA at the feedback link here: http://www.oecd-nea.org/confdb/confdb/conf?id=146

Thanks,
Adam

10

Thank you Mr. Nelson.
I have changed 03c of first line in U-235.12c to 12c. Path is fine in that. So it works well now.
Still it is a problem for some other Elements to like Nb (I found in that). I am doing same for these 03c error.

Thank you very much once again Paul And Adam.