Energy deposition and associated temperature

Physics, Transport and Magnetic Fields
1

Dear FLUKA users and experts!!!

I want to obtain a dependence of energy deposition in vacuum window foil (titanium with thickness 127um) on a temperature. How can I calculate it?

Thanks in advance
Best regards
Zohrab

3

Dear @zamirkhanyan,

A few comments regarding your question:

  1. For the energy deposition, I would need to know if you want all the energy deposited in your foil (SCORE card) or the spatial distribution of energy deposited in a mesh (USRBIN card). For more detail and more types of scoring I leave here a presentation about this topic:
  1. For the definition of the material in the foil, the titanium, it is a predefined material in FLUKA. The only fact to consider is that you cannot define the temperature for the material, but you can variate the density of it. To see more about material in FLUKA I recommend you this lecture:

Let me know If you need more help,
Cheers,
André

2 Likes
4

Dear Andre

Thanks a lot for the answer and the threads attached.
I got very helpful information.
I was estimated the energy deposition in window by using USRBIN card.
I want to convert the energy deposition into temperature, which will allow me to estimate the temperature rise in the window under irradiation.

So I would like to know how can I do it?

Best regards
Zohrab

5

Dear @zamirkhanyan,

Here I attach a possible solution:

Screenshot from 2021-04-28 08-45-34
Screenshot from 2021-04-28 08-45-34833Ă—458 19.6 KB

Probably this can work well as a first approximation.

Let me know if it has sense to you, otherwise we can keep discussing it.

Cheers,
André

1 Like
6

Hello @zamirkhanyan,

in addition to Andre’s answer there is one important point if you want to convert energy deposition in temperature. You must make sure that the electromagnetic cascade is fully transported, meaning you must not have an EMF card with the parameter off in your input and transport thresholds for photons, electrons and positrons should be low. Otherwise they will be created but not transported and their energy is deposited on the spot, which will lead to over-estimation (sometimes quite huge over-estimation!) of your results.

Cheers
Chris

1 Like
7

Dear @zamirkhanyan,

Besides the points given above, I think maybe another issue is how to describe the thermal response of the target. As the result of FLUKA is the energy deposition of per primary, for the thermal response of the target, maybe also need to know the beam current to build the full spatial and temporal energy deposition in the target. If a simple adiabatic description is not enough, this energy deposition should be used as the source term for a partial differential equation (typically the Fourier equation) for the thermal field. That means, maybe need to combine the results of FLUKA with some other methods which can solve the thermal equation, such as finite element or finite difference method for a solution.

Best regards,
Xiao

8

Dear André, Chris, Xiao

Thank you very much for the helpful information.
Now I have more clarity.

Thanks and regards
Zohrab

1 Like