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DPM injection mass problem

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Old   August 22, 2016, 18:29
Unhappy DPM injection mass problem
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Hi,


I have an unsteady stream of multi-component particles being injected into turbulent flow. The problem is the mass of particles in parcel suddenly changes to a larger value after a couple of iterations.

After a point, diameter gets doubled while the number of particles in parcel gets divided by 8!

I have evaporation only. How is it possible for the mass in particle to get eight time larger?! Table below shows two sample particles from before and after increase in mass. I have tried the test case without coalescence and results are the same.




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Old   August 23, 2016, 12:09
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As it turns out, when KHRT breakup model is used this happens!

Apparently KHRT is only reliable for high Weber flows, I was injecting the particles way outside the fluid jet, I guess KHRT becomes unstable during particle's long flight outside the fluid jet where flow is slow.
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Old   May 29, 2019, 22:52
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Quote:
Originally Posted by siramirsaman View Post
As it turns out, when KHRT breakup model is used this happens!

Apparently KHRT is only reliable for high Weber flows, I was injecting the particles way outside the fluid jet, I guess KHRT becomes unstable during particle's long flight outside the fluid jet where flow is slow.
Hi,

I have the same problem as you. I am injecting particles into a turbulent, high Weber number gaseous medium. Exactly after injecting, the size of my injected particles roughly doubled, whereas the coalescence in stochastic collision option is also disabled. This issue does not happen to TAB breakup model, while for KHRT and wave breakup model are true. In fact, I have to use KHRT for my breakup, because in my case, after injection the medium is of low Weber number until reaching the focal point of gas stream and particles , i.e. high Weber number region and for me, the breakup model is important to get a better particle size distribution. I got stuck at this point. what can I do to resolve doubling in particle mass?
any help would be appreciated.
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