How to include dissociation & recombination effects on tritium transport through 316 steel pipe

User Support
1

Hi all,

I’m new to the community, and am running a simple diffusion problem for a purge gas system. As a first approximation to build up from, I have T2 at 100Pa inside a 5mm thick stainless steel pipe and am finding the time evolution of tritium inventory and flux in and out of the pipe.

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I initially used SievertsBC at the inner surface and FixedConcentrationBC(concentration=0) on the outer surface, and it all ran fine. I now want to explicitly account for dissociation effect at the inner surface and recombination at the outer surface. I believe I can do this by using:

festim.DissociationFlux to replace the SievertsBC at the inner surface

and

festim.RecombinationFlux to replace the FixedConcentrationBC at the outer surface

However, when I tried swapping the boundary conditions, I got the following error:

AttributeError: module ‘festim’ has no attribute ‘RecombinationFlux’

Please could someone tell me -

  1. If my approach is sound and makes sense
  2. Why I’m getting this error

Thanks very much!

2

Hi @srichr and welcome to the FESTIM discourse! A few questions:

What version of FESTIM are you using?

If you’re using FESTIM2 then I would point you to this tutorial

my_bc = F.SurfaceReactionBC(
    reactant=[H, H],
    gas_pressure=P_H2,
    k_r0=...,
    E_kr=...,
    k_d0=...,
    E_kd=...,
    subdomain=boundary,
)