Hello everybody, I'm writing to know if someone has an example of an eccentric funnel flow simulation. My idea is to run a simulation and use the output to create an animation. I could fulfill a cylindrical flat-bottom silo and discharge it through an eccentric outlet, but the result resembles much more a mass flow.
So, I guess the physical properties are not corrected.
Any help are more the appreciated.
Greetings
mdasilva | Tue, 08/14/2018 - 06:11
Maybe the problem is that I
Maybe the problem is that I did not configured the dump command correct.
I found this video and it seems to be quite similar to what I need.
https://www.youtube.com/watch?v=Gn_AUcbRAbE
What variable should I dump?
Greetings
richti83 | Tue, 08/14/2018 - 07:49
You could start here: https:/
You could start here: https://www.cfdem.com/forums/tutorial-3-dem-flow but you need to calibrate the friction values (e.g. using an Angle of Repose test [1], a Jenicke Shear tester and/or a drawn down tester)
For Post-Prozessing I would recommend Point Gaussian: https://www.cfdem.com/comment/16471#comment-16471
[1] https://www.researchgate.net/publication/309136157_Scalability_of_angle_...
mdasilva | Tue, 08/14/2018 - 23:26
Thank you so much richti.
Thank you so much richti. Your examples will be very, very useful.
The parameters for the simulation was given by a group of researchers. According to them, the angle of repose of particles is 28º. So, if I'm not wrong, it gives me a friction coefficient of tan(28º) = 0,5317.
I didn't check yet your examples, but maybe I'm a little bit confused about setting coefficients in a LIGGGHTS simulation. This is what I have for the simulation I'm talking about:
fix m1 all property/global youngsModulus peratomtype 1.5e8 2.5e7
fix m2 all property/global poissonsRatio peratomtype 0.25 0.25
fix m3 all property/global coefficientRestitution peratomtypepair 2 0.7 0.5 0.5 0.5
fix m4 all property/global coefficientFriction peratomtypepair 2 0.532 0.275 0.275 0.5
Actually, the last fix says the coefficient of friction between particles is 0.532 and between particles and walls is 0.275 (galvanized steel). By the way, the particles are supposed to be amaranth seeds.
Greetings.
richti83 | Wed, 08/15/2018 - 16:06
Yes thats the way material
Yes thats the way material properties are set. I would recommend to activate rolling friction for p-p and p-w contacts (I prefer model epsd2). And I would reduce coefficientRestitution even if some researchers say it is 0.7 a damping of only 30% is quite bumpy. I use cor=0.2 all the time.