[Cornelia]

Dear all,

I am simulating a turbulent air flow with sand particles of multiple sizes. The particles are expected to either reach the so-called "Killing_Wall" or the Outlet of my domain. As my situation is steady-state, I am using simpleReactingParcelFoam of OF 2.3.1.

Below is the output I get after each particle tracking. I can read that 3343 parcels have reached the Killing_Wall and 5967 have reached the outlet, but 690 parcels got stuck anywhere in the domain. With paraFoam I can see that my maxTrackTime criteria was hit only for two of them. All the other tracks out of these 690 look nice so far, but stop suddenly somewhere in the middle of the flow field.

So I wonder what could have been happened to them and how to avoid such a high failure rate.

Solving 3-D cloud reactingCloud1

--> Cloud: reactingCloud1 injector: model1
Added 1000 new parcels


--> Cloud: reactingCloud1 injector: model2
Added 1000 new parcels


--> Cloud: reactingCloud1 injector: model3
Added 1000 new parcels


--> Cloud: reactingCloud1 injector: model4
Added 1000 new parcels


--> Cloud: reactingCloud1 injector: model5
Added 1000 new parcels


--> Cloud: reactingCloud1 injector: model6
Added 1000 new parcels


--> Cloud: reactingCloud1 injector: model7
Added 1000 new parcels


--> Cloud: reactingCloud1 injector: model8
Added 1000 new parcels


--> Cloud: reactingCloud1 injector: model9
Added 1000 new parcels


--> Cloud: reactingCloud1 injector: model10
Added 1000 new parcels

Cloud: reactingCloud1
Current number of parcels = 690
Current mass in system = 0.161925
Linear momentum = (0.1299050046 -0.0197194001 -2.564621241)
|Linear momentum| = 2.567984867
Linear kinetic energy = 25.89802124
model1:
number of parcels added = 1000
mass introduced = 0.25
model2:
number of parcels added = 1000
mass introduced = 0.25
model3:
number of parcels added = 1000
mass introduced = 0.375
model4:
number of parcels added = 1000
mass introduced = 0.375
model5:
number of parcels added = 1000
mass introduced = 0.5
model6:
number of parcels added = 1000
mass introduced = 0.3
model7:
number of parcels added = 1000
mass introduced = 0.2
model8:
number of parcels added = 1000
mass introduced = 0.125
model9:
number of parcels added = 1000
mass introduced = 0.075
model10:
number of parcels added = 1000
mass introduced = 0.05
Parcels absorbed into film = 0
New film detached parcels = 0
Parcel fate (number, mass) : patch Wall
- escape = 0, 0
- stick = 0, 0
Parcel fate (number, mass) : patch Killing_Wall
- escape = 3343, 0.9567
- stick = 0, 0
Parcel fate (number, mass) : patch Inlet
- escape = 0, 0
- stick = 0, 0
Parcel fate (number, mass) : patch Outlet
- escape = 5967, 1.381375
- stick = 0, 0
Parcel fate (number, mass) : patch Symmetry
- escape = 0, 0
- stick = 0, 0
Temperature min/max = 373.15, 373.15
Mass transfer phase change = 0
Mass transfer devolatilisation = 0
Mass transfer surface reaction = 0

[luchen2408]

hello, conerlia, have you solve the problem? I have the same problem as you mentioned, I took simpleFoam solver to inject liquid particles(looked as solid particles). but I have more questions:

1. the gravity seems doesn't act on the particles, even I set the gravity.

2. the paritcles will flow along the wall for a distance after it hit the wall.

3. There are a lot of particles stuck in the flow doamin, not stick to the wall and not to get to the outlet. That may be the calculation doesn't coverge. I also prelong the maxtracktime, but if I do that, I found all the particles will stuck in the doamin, no sticking the wall and no getting to the outlet.

[Cornelia]

Hi luchen2408,

thank you for your answer. But unfortunately I did not solve my problem. My simulation works fine apart from the unfinished tracks. In my case the problem does not only appear next to the wall, but some particles also vanish in the middle of the domain without any obvious reason.

Gravity is working correctly in simpleReactingParcelFoam. If you compiled your own version of simpleFoam (as the standard simpleFoam does not support particle tracking), the error is most probably in your code.


Best regards
Cornelia

[luchen2408]

hello, conerlia, Thanks for your reply. In my simulation, I took swak4foam to introduce the particles. it is easier to compile a new solver. I will check the code once again. Thanks.