DEPLETION: Starting transport-coupled and transport-independent depletion

Fandresena · March 22, 2026, 3:09pm

Hi,I just try to start a transport-coupled and transport-independent depletion simulation, so i read the documentation user’s guide about depletion but i didn’t understand how it really works: the structure of the code: we needed to define the power, time steps, and how to choose the Operator in what situation? What we really need in each different operator (in CECMIntegrator???, in CoupledOperator???..)
Someone can explain How to developp a transport-coupled and transport-independent depletion?

wahidluthfi · March 23, 2026, 10:35pm

You might want to check the depletion notebook from openmc for transport-coupled depletion.

github.com/openmc-dev/openmc-notebooks

depletion.ipynb

develop

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Pincell Depletion\n",
    "This notebook is intended to introduce the reader to the depletion interface contained in OpenMC. It is recommended that you are moderately familiar with building models using the OpenMC Python API. The earlier examples are excellent starting points, as this notebook will not focus heavily on model building.\n",
    "\n",
    "If you have a real power reactor, the fuel composition is constantly changing as fission events produce energy, remove some fissile isotopes, and produce fission products. Other reactions, like $(n, \\alpha)$ and $(n, \\gamma)$ will alter the composition as well. Furthermore, some nuclides undergo spontaneous decay with widely ranging frequencies. Depletion is the process of modeling this behavior.\n",
    "\n",
    "In this notebook, we will model a simple fuel pin in an infinite lattice using the Python API. We will then build and examine some of the necessary components for performing depletion analysis. Then, we will use the depletion interface in OpenMC to simulate the fuel pin producing power over several months. Lastly, we will wrap up with some helpful tips to improve the fidelity of depletion simulations."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [

This file has been truncated. show original

The details on python api for depletion calculation could be seen in Depletion - Python API.
I haven’t tried the transport independent depletion, but I think the Transport Independent Depletion section has described this feature. So you can try it before setting up the integrator and do the integrator.integrate().

Also, you might want to ask this kind of question on the User support section of the forum, which will catch more attention and show the related topics, such as this one Negative atoms when using openmc.deplete.IndependentOperator from Shimwell and others.

Shimwell · March 25, 2026, 3:13pm

transport-independent can be done with material.deplete()

There are a few well commented examples here for fixed source depletion

Topic		Replies	Views
OpenMC Independent Depletion Operator Split Time Steps User Support	3	443	June 14, 2023
Depletion module of openmc User Support	10	505	December 2, 2023
Depletion not working User Support	1	585	September 20, 2022
Capabilities of OpenMC User Support	18	1908	February 16, 2022
Have a trouble during the depletion of the openmc User Support	3	287	June 24, 2024

DEPLETION: Starting transport-coupled and transport-independent depletion

Related topics