DPM Particles injection
 

Hi ,

I have a problem simulating particles in 2D. I have a simple geometry surface where this is air inlet and air outlet . There is a Rectangle surface which is used to inject the particles. When run the calculation it says Zone not slit and the particles are not injected. I don't know what is the problem. Only air flow contours are made . Kindly Help me through this I am stuck.

Thanks.

Regards,

Muhammad Talha

Do you get the same warning if you don't use particles?

yes it stays the same.

Then that warning has nothing to do with your particles.

Second question: are you 100% sure that your initial particle locations are inside your domain? (do you use injection files?) be careful if they are at the boundary of the domain, fluent might place them just outside, and ignore them.

yes its inside the domain . There is rectangular surface which is at the middle of the surface geometry, which is Boolean subtracted. from That surface I am injecting the particles. I did not used UDF Injection Files. I gave a velocity , mass flow rate and diameter.

You say that the particles were not injected.
What exactly did you do to come to that conclusion?

I mean to say that the I can not see the particles injected through the rectangular surface.

What injection method did you use to inject particles in the domain? Why not try surface injection at first and see if there is a problem or not.
Also, Does your setup work if the DPM is not enabled?

Hi,
I have used DPM method, I tried Surface injection , The problem is still there. It works when only air is flowing through inlet and going to outlet.

What do you get in the TUI when you (try to) release particles?

(and just to be sure: have you ever successfully released particles in a different fluent simulation?

The console says 0 particles tracked in 2D. I have tried with 3-D case with a circle injecting on one face of the cube. That works fine. I can see the particles there.

Can you just copy the literal text that shows up?

Hi look at this , I have attached the pic.

I see that 100 particles were injected. And you are plotting particle traces. So why again do you think it failed? Can you make a picture of something that failed?

The particles injected are incomplete. Moreover there is no fate information. The particles track is just air flowing through it.

The paths are incomplete, which means that the calculation ended before particles reached an exit.

So no finished paths, no fates to be reported.

Clearly, your particles were released. They just stayed inside your domain until the end of the calculation, your image supports that.

So, everything worked as it should. You don't have a problem...

Thanks for the reply. ok it means i should further reduce the time step size and increase the number of steps.

and ONLY DPM model is sufficient for injecting aerosol particles? i have selected as inert particle of water liquid and fluid air in the material then i gave the injection velocity and inlet velocity and pressure outlet. Then hybrid Initialization.

will this be enough for this case? or i have to use VOF or Species transport?
Kindly guide me through it.

?

No, it does not mean that. Do you expect that particles will leave your domain if you simulate longer? Your picture does not really look like that... Why can't you accept that this is the final result? What is wrong with it???

If anything, only increase number of steps. Don't reduce the time step further, why would you....

No i don't want to leave the domain. I just want to remain in the domain. I am confused which particles are these , i mean to say that i have air also coming and injecting water liquid through same inlet. So these tracks are of which one? have I given the air correct boundary condition?

and further ONLY DPM model is sufficient for injecting aerosol particles? i have selected as inert particle of water liquid and fluid air in the material then i gave the injection velocity and inlet velocity and pressure outlet. Then hybrid Initialization.

will this be enough for this case? or i have to use VOF or Species transport?