the advantage of this approach is that it is much faster as the transport simulation is only done once to get reaction rates per source neutron then they are assumed to be the same for each timestep. This is a reasonable approximation for low burnup simulations and has a significant saving for depletion simulations with many time steps
holding off on this as I'm getting negative atoms for the results. I've raised a topic on openmc discourse. I notice there are some planned changes for the microxs class so I shall try again after that.
this example is an adapted version of the CoupledOperator depletion example
the advantage of this approach is that it is much faster as the transport simulation is only done once to get reaction rates per source neutron then they are assumed to be the same for each timestep. This is a reasonable approximation for low burnup simulations and has a significant saving for depletion simulations with many time steps