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banerji March 17, 2010 18:52

particle tracking
 
i am simulating a water treatment reactor:it is a simple pipe with with one inlet and one outlet. When I make particle Injection they stop in the middle and I see the report as:

injected:12 escaped:0 incomplete:12

why aren't they coming out and when I checked pathlines they look okay


Please help me if you have an idea

wiebe March 19, 2010 11:32

Hi Banerji,

It seems that there is a maximum number of simulation steps for your particle tracking. I don't know what software you use, but there is probably a setting for this somewhere. (Increase it to have more steps.)

Regards,
Wiebe.


Quote:

Originally Posted by banerji (Post 250492)
i am simulating a water treatment reactor:it is a simple pipe with with one inlet and one outlet. When I make particle Injection they stop in the middle and I see the report as:

injected:12 escaped:0 incomplete:12

why aren't they coming out and when I checked pathlines they look okay


Please help me if you have an idea


carmen March 19, 2010 11:44

Hi I’m user of fluent.In my thesis i investigate two phase flow with solid-liquid.We use magnetic force to a field whic magnetic and nonmagnetic particles are suspended in a liquid for separating magneting particles from nonmagnetic particles.can you help me for choosing true model. DPM,mixture,euler which have to be choosen.My solution is dilute

wiebe March 19, 2010 12:21

Hi Carmen,

For this you probably need to track individual particles, (that means the DPM model) In addition to this, you will need to model the influence of the magnetic field somehow. There is a magnetohydrodynamic module, (search for MHD) but I have no experience using it.

Good luck,
Wiebe.

carmen March 19, 2010 13:27

thks wiebe but i have a problem for lading particle particle will flow with flow but in dpm it ask me start end stop time what will i do

banerji March 20, 2010 17:38

Thank you very much Wiebe, I increased the number of steps and all particles escaped. by the way i am using Fluent.

banerji March 20, 2010 17:50

Another small question: does fluent select automatically the appropriate number of particles to inject ? I want to increase the number of particles but i can't find how to do it.

wiebe March 24, 2010 10:48

The number of particles tracked depends on the type of source. single is just one particle, surface is one particle per cell on the surface, but for example a cone lets you select the number of particles yourself.

wiebe March 24, 2010 10:55

Hi Carmen,

the start and stop times affect when the particles are released. If for instance your simulation is 100 seconds, but you only want to release a puff of smoke in the first two seconds, set the start time to 0 and the stop time to 2 for the injection. Particles will be tracked the rest of the time, but no new particles will be released.

Wiebe.

alikami March 27, 2010 15:07

gas - particle flow thru CD nozzle
 
Hi i am simulating flow through a convergent-divergent conical nozzle...
with a laminar only gas solution convergent
with particles also converged but no difference ????:eek:
any one can help,,,,
Thanks
Alikami


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