I am using the combination of Synrad+ and Molflow+ to estimate the pressure profile within a dipole chamber. Therefore I follow the explanation given in the SynRad documentation chapter.
I used Synrad 1.2 and I always got pretty high outgassing rates. In the version 1.3.4 the rates are much lower and in the same region as I calculated them in front. Using the same model they differ some orders of magnitude.
In Synrad the values are the same (Power, Flux) in both versions. I looked in the change log but I couldn’t find a modification that would cause this change in outgassing.
Just to understand if I may do a mistake. Have you changed anything in the new Synrad version concerning the desorption files adn how the are being saved?
If you need more information about the way I am doing the simulations just ask. I hope you can help me with this issue.
Dear Andreas, i recommend you to use 1.3.4. Unfortunately not mentioned in the changelog, synrad 1.2 used mbar.l/s yield values, whereas 1.3 uses molecule/photon, as it should. Currently on holiday, i will get back to you when back at cern, doing coupled simulations is not straightforward and id be happy to explain the caveats and tricks in detail. Marton
If you're still working on the problem, here are some thoughts on importing dynamic desorption.
- You should use the new 2.6.7 beta version, as it provides additional details for every facet about the dynamic desorption:
- You would also need a conversion file, like those you find in the "Desorption yields" folder in your Molflow installation. A typical file (Groebner CH4) looks like this:
The first column contains increasing conditioning doses (in absorbed photons/cm2), and the second column contains the corresponding flux values. Between the dose (X) values a logarithmic interpolation is made, outside the dose values an extrapolation is performed. This extrapolation would result in very high yields for low doses, that's why the first two yield values in the first two lines are practically the same (1.1E-4 and 1.05E-4). This means that in the example, below 1.4E18 photons/cm2, the yield will be approximately the same, while for doses larger than 1.43E21photons/cm2, the yield will decrease to one-tenth every magnitude.
If total outgassing (in Global Settings) and individual facet outgassings seem to be in order, then you can trust the imported values.
thank you very much for the update and your thoughts on the topic. I will start using the beta version now. If I have some trouble (and probably I will) I would like to contact you again.
