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ljp September 20, 2010 15:11

Uncoupled calculation for discrete phase?
Hi all,

I'm trying to simulate a liquid spray problem. as a start, I want to inject a single stream of water droplets into a gas field and calculate the trajectory using uncoupled method (the droplets do not have impact on the gas field).

What I did was: at the "Discrete phase model" panel, I didn't select the "Interaction with Continuous phase", but selected the "Unsteady particle tracking" and entered the relevant parameters. I defined the injection and started running. Then after some time, when I tried to display the particle tracks, I found the domain is empty, does not have any particles in it! I don't know where I made mistakes. Could anyone please point out what might be the problem? or tell me the correct procedure of performing uncoupled calculation?

Also, at the "display particle tracks" panel, in the particle variables list there is a variable "particle Weber number". I didn't find its definition in the manual (I want to check whether it's defined the same way as what I know from the literature). Does anyone know its definition? Thanks a lot!!


sreerao September 21, 2010 07:07


Try steady particles, and check particle trackings, it should work for you.


ljp September 21, 2010 11:16

Hi Sreerao, thank you for your reply. I tried using steady particles and I got them in the domain! but since I tried to see how the droplets breakup in the gas field, I turned on the breakup model, then the unsteady particle tracking was automatically selected, and the droplets are lost again. (the total no. of particles is reported to be zero). Does that mean that the uncoupled calculation only works for steady particle tracking? and the uncoupled calculation cannot be used to study droplet breakup?

Thanks a lot!

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