Synrad: Transparency param: 1.5mm_thick_alu

Good morning,

I would like to configurate the transpareny parameters of different materials.

In Synrad, the transparency param are already configurated for 1.5mm thick alu. (Inside folder: synrad_1.4.30/param/Materials)
I’ve tried to calculate them again on my own to see if they match. Unfortunately the don’t match.

In my calculation if used the Table Z=13 Alu from NIST and the formulas from Márton Ady’s thessis chapter 2.5.1.2 Transparency.

The expression I’ve used in Excel to calculate the transparency is: EXP((-µ/ρ)*(0.15/sinθ)). Grazing angle from 0 to 1.57. With that, the transparency calculated is much higher than the one preconfigurated in Synrad.

The results are more similar if I use: EXP((-µ/ρ)*(1.5/sinθ)). However, I think that the thickness should be written in cm.

Please, could you help me on this?
Thank you
Oriol Traver

Hello Oriol,

Well done spotting this error.

I went back to my thesis work files and I used this Excel sheet to generate the Synrad file:
alu attenuation.xlsx (62.2 KB)

On the top left (Y1 cell) you can adjust the thickness in cm.
With trial and error, it seems that I get back the results in the Synrad file by setting it to 1cm (not 1.5mm). I will rename the file in future releases (in fact, we already renamed it in the internal version, just not the outdated 1.4.30 from early 2021. A new version is coming soon)

For your info, the motivation was to model 1cm of aluminium, and if your actual wall thickness is less (let’s say 1.5mm=0.15cm), then set the facet opacity to 0.15. This way, for any thickness below 1cm you can use the same parameter file, just “convoluted” by an opacity value that you can change in Synrad.

Of course, there’s no excuse for the misleading filename, nice that you found it, and sorry for the time spent with debugging it.

Cheers, Marton

Hello Marton,

Thanks for your help, I could configure different materials and run the simulations. The results are good!

Cheers, Oriol