Chain Depletion

[Javier Gonzalez]

Hello,

Please, someone can tell me if the depletion chain generated by the script "openmc-make-depletion-chain" (which creates the file "chain_endfb71.xml") can be used to analyze advanced  systems such as liquid salt cooled reactors?

Thanks,

Javier

[Andrew Johnson]

Hi Javier,

The main drawback to that script is that your capture branching ratios will not match the true spectrum of your problem. Instead, I would first recommend using either the Fast Spectrum ENDF/B-VII.1 Chain or Fast Spectrum Simplified Chain found at https://openmc.org/depletion-chains/. Alternatively, if you have a more representative collection of isomeric branching ratios, you can apply these to any depletion chain using the openmc.deplete.Chain.set_branch_ratios method.

Regards,

Andrew

[Javier Gonzalez]

Hi Andrew,

Thanks for your reply, now, I am having a new issue. In a previous post, it was recommended setting the OPENMC_CROSS_SECTIONS environment variable, I did it and my depletion analysis was running. Today, I restarted the computer and I am having again the error message "OSError: No cross_sections.xml specified in materials." I followed the steps to set up the OPENMC_CROSS_SECTIONS environment variable but it is not working. 

Any idea on what may be happening?

Javier

[Paul Romano]

Hi Javier,

That exception is only raised if the OPENMC_CROSS_SECTIONS is not set. You can see the code where that comes from here (notice the check first for OPENMC_CROSS_SECTIONS):

https://github.com/openmc-dev/openmc/blob/f4e46fd620ddb96755f73df6d2d079ea694ae8a6/openmc/deplete/operator.py#L694-L708

To double check, you could open a Python interactive prompt and make sure it can see the environment variable. For example, on my machine this is what I get:

~ $ python
Python 3.7.5 (default, Oct 31 2019, 12:53:15)
[GCC 9.2.1 20191008] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> os.environ['OPENMC_CROSS_SECTIONS']
'/opt/data/hdf5/nndc_hdf5_v15/cross_sections.xml'

Best regards,

Paul

--
You received this message because you are subscribed to the Google Groups "OpenMC Users Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to openmc-users...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/openmc-users/63ea8114-3434-4d15-9d61-e2a686ae516a%40googlegroups.com.

[Javier Gonzalez]

Hi Paul,

Thanks for replying.

One more time, I followed what was suggested but unfortunately the problem persists. Please, see what I did:

----------------------------------------------------------------

(base) javier@hunter:~$ python

Python 3.7.4 (default, Aug 13 2019, 20:35:49) 

[GCC 7.3.0] :: Anaconda, Inc. on linux

Type "help", "copyright", "credits" or "license" for more information.

>>> os.environ['OPENMC_CROSS_SECTIONS']

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

NameError: name 'os' is not defined

>>> import os

>>> os.environ['OPENMC_CROSS_SECTIONS']

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

  File "/home/javier/anaconda3/lib/python3.7/os.py", line 678, in __getitem__

    raise KeyError(key) from None

KeyError: 'OPENMC_CROSS_SECTIONS'

>>> exit

Use exit() or Ctrl-D (i.e. EOF) to exit

(base) javier@hunter:~$ bash

(base) javier@hunter:~$ export OPENMC_CROSS_SECTIONS=/home/javier/Documents/OpenMC/DataENDF-7.1/cross_sections.xml

(base) javier@hunter:~$ python

Python 3.7.4 (default, Aug 13 2019, 20:35:49) 

[GCC 7.3.0] :: Anaconda, Inc. on linux

Type "help", "copyright", "credits" or "license" for more information.

>>> import os

>>> os.environ['OPENMC_CROSS_SECTIONS']

'/home/javier/Documents/OpenMC/DataENDF-7.1/cross_sections.xml'

>>>

----------------------------------------------------------------

Apparently, the environment is defined correctly but I'm still having the same error. Any new recommendation?

Thanks,

Javier

To unsubscribe from this group and stop receiving emails from it, send an email to openmc...@googlegroups.com.

[Javier Gonzalez]

Hi guys,

Now, I defined the environment variable modifying the.bashrc file and it is working. It seems I was doing wrong. Here what I did:

~$ vi .bashrc 

~$ vi .bashrc 

     export OPENMC_CROSS_SECTIONS=/path/to/cross_sections.xml

~$ source .bashrc

Thanks,

Javier