OpenMC example test run: ModuleNotFoundError: No module named 'openmc'

I am a new entrant to OpenMC, trying to run an example test problem in ‘OpenMC/examples/lattice/simple’ to understand how OpenMC can be executed and offcourse its input/output structure. Earlier i built OpenMC from source in my linux system and created the executable and made sure its accessible from the CLI through the PATH environment. While executing this test i could not get python to understand the module ‘openmc’ receiving the following error.
(base) abalasub@freia013> python
Traceback (most recent call last):
File “”, line 1, in
import openmc
ModuleNotFoundError: No module named ‘openmc’

I suppose this could be a simple fix, but given that i am new to OpenMC i am kind of struggling. Probably some one could pointe me to the right direction.
Kind regards,

Hi @abarun and welcome to the community. In addition to building the executable for OpenMC, you will need to install the Python API as detailed in these instructions.

Hi Paul,
Thanks for that. It’s all working now. I could now be able to run my first simulation in OpenMC. I am currently trying to build a model that can perform neutron transport calculations and eventually compute the damage dose DPA. I would like to get your suggestions as to how this can be done in OpenMC.
Kind regards,

@abarun You can tally the damage-energy score in OpenMC, which uses the MT=444 data computed by NJOY. To get from the damage-energy score to dpa/sec, you can follow the guidance given in the NJOY/HEATR manual:

The damage output from HEATR is the damage energy production cross section (eV-barns). As in Eq. 160, multiplying by the density and flux gives eV/s. Dividing by 2Ed gives displacements/s. This result is often reduced by an efficiency factor (say 80%) to improve the fit to the empirical correlations.

Note that the tally in OpenMC will give you a quantity in [eV/source particle], which you’ll need to convert to [eV/sec] (see further guidance here).