March 28, 2021 at 2:17 pmza36kuzoSubscriber
I am modelling the blockage of Particle in an air-filled pipe using Macroscopic particle model MPM. By means of particle-based numerical simulations of gravity-driven flows in vertical pipes and test the material transport by adding a helical texture to the inner-wall of the pipe, however, in the first case without helix structure, the blockage has been achieved due to the collision, but some of particle pairs tend to overlap, and I reserved Warning: 1 particle pairs are overlapping!
In the second case, by adding the helix, the most of my particle are lost out of the domain in short time after running the simulation. Please check the images to get a better image of the problem.
Initial time step size 1e-04
I tried to reduce the coefficient of restitution , in order to induce the loss energy for MPM particle once it hits the wall and can ensure that the MPM does not lose contact with the wall ( please correct me if its wrong), and set a high value for minimum drag force for particle detachment., but it does work.
Any help would be greatly appreciated.
Regards!March 29, 2021 at 1:44 pmRobAnsys EmployeeTry decreasing the time step. If the step is too big the particles can overlap before that's noticed by the solver and the amount of energy this stores then causes the particles to separate VERY quickly. nMarch 31, 2021 at 6:38 amza36kuzoSubscriberThanks for replaying, I will try it!nApril 1, 2021 at 10:22 amza36kuzoSubscriberI reduce the time step size to 10^-6,but it doesn?t resolve this overlapping!nApril 1, 2021 at 10:41 amRobAnsys EmployeeHow fast are the particles moving and how big are the cells? nApril 2, 2021 at 6:16 amza36kuzoSubscriberFor MPM the mesh element size must be smaller than the particle diameter size, so in my case particle size = 0,0012 m and element size was 0.0005 m. nDue to the helix structure the particle moves very very fast, so they lost faster in the domain, compared with the pipe without helix. I noticed that in both case the particle pairs tend to overlap, so far they are close to wall with high velocity( 2-5) m/ s, specially when particles are jamming in the narrow pipe.nViewing 5 reply threads
Ansys Innovation Space
- You must be logged in to reply to this topic.
Earth Rescue – An Ansys Online Series
The climate crisis is here. But so is the human ingenuity to fight it. Earth Rescue reveals what visionary companies are doing today to engineer radical new ideas in the fight against climate change. Click here to watch the first episode.
Subscribe to the Ansys Blog to get great new content about the power of simulation delivered right to your email on a weekly basis. With content from Ansys experts, partners and customers you will learn about product development advances, thought leadership and trends and tips to better use Ansys tools. Sign up here.Trending discussions
- Suppress Fluent to open with GUI while performing in journal file
- Floating point exception in Fluent
- What are the differences between CFX and Fluent?
- Heat transfer coefficient
- Getting graph and tabular data from result in workbench mechanical
- The solver failed with a non-zero exit code of : 2
- Difference between K-epsilon and K-omega Turbulence Model
- Time Step Size and Courant Number
- Mesh Interfaces in ANSYS FLUENT
- error in cfd post
© 2023 Copyright ANSYS, Inc. All rights reserved.Ansys does not support the usage of unauthorized Ansys software. Please visit www.ansys.com to obtain an official distribution.