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DPM collision rate normalized?

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Old   March 5, 2020, 08:33
Default DPM collision rate normalized?
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I have a 2D model with DPM, and I want to normalized the collosion per partice (i.e. number of collosion events divided by number of particles).
Is there a way to define a function/parameter and print it with each time step?

I tried to normalize collosion rate by particle concentrations, applying densities etc. The number of particles in domain, however does not match to the number which I get from Report/Discrete/Summary. Any idea why?

thanks in advance
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Old   March 5, 2020, 08:54
Default Collision
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Which collision model are you using? Is it O'Rourke or DEM?
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Old   March 5, 2020, 09:00
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Quote:
Originally Posted by vinerm View Post
Which collision model are you using? Is it O'Rourke or DEM?
I use O#Rourke.

Does it make a difference, I am curious?
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Old   March 5, 2020, 10:45
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There are significant differences since one is statistical while other one is not. However, it is not of much relevance here. If the number of particles is fixed in your case, then it is much easier because you can create a custom field function. However, if that is not the case, then you can define it as ratio of volume integral of collision rate and volume integral of number density.

Do note that the summary displays both, number of parcels and number of particles and most of the times these will be different. Tracking is done for parcels and not for particles.
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