CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

CFD-DEM Simulation - Particle Size compared to mesh cell size

Register Blogs Members List Search Today's Posts Mark Forums Read

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   February 24, 2016, 12:37
Default CFD-DEM Simulation - Particle Size compared to mesh cell size
  #1
Member
 
Nadish Saini
Join Date: Feb 2014
Location: Raleigh, North Carolina
Posts: 39
Rep Power: 12
90nash is on a distinguished road
Hello Foamers,
I have a conceptual question to which i am not able to find an answer.

I am performing ONE-WAY coupled simulation of micron sized particles suspended in a turbulent flow field. The concentration of particles is low enough for me to consider only one-way coupling. i am solving the flow field using LES. The mesh cell size is generally larger than the particle size. However, near the wall, since LES requires DNS type resolution, the mesh cells are smaller than the particle dimensions. My questions:

1. For one-way coupled simulations, is it necessary to have the condition that particles must be smaller than mesh cells?

2. There must be a way to deal with the situation where DEM particles are larger than mesh cells but i could not find any reference article for it. Can someone please guide me with this.

Thanks a ton!
90nash is offline   Reply With Quote

Old   February 24, 2016, 12:40
Default
  #2
Senior Member
 
Filippo Maria Denaro
Join Date: Jul 2010
Posts: 6,793
Rep Power: 71
FMDenaro has a spectacular aura aboutFMDenaro has a spectacular aura aboutFMDenaro has a spectacular aura about
I think your question is more general than an OF problem...

Specifically, I think there is no physical meaning in having a computational mesh size smaller than the particle diameter...
Do your particles have a relevant inertia?
FMDenaro is offline   Reply With Quote

Old   February 24, 2016, 12:51
Default
  #3
Member
 
Nadish Saini
Join Date: Feb 2014
Location: Raleigh, North Carolina
Posts: 39
Rep Power: 12
90nash is on a distinguished road
Quote:
Originally Posted by FMDenaro View Post
I think your question is more general than an OF problem...

Specifically, I think there is no physical meaning in having a computational mesh size smaller than the particle diameter...
Do your particles have a relevant inertia?
Hi. Thank for your reply.

I am not sure what you mean when you say:
"there is no physical meaning in having a computational mesh size smaller than the particle diameter".

The particles i am considering have a mean diameter of 200e-6 m. Thus their inertia would be small, no doubt. The smallest cell dimension (near wall) is 12e-6 m for LES simulation.
90nash is offline   Reply With Quote

Old   February 24, 2016, 13:16
Default
  #4
Senior Member
 
Filippo Maria Denaro
Join Date: Jul 2010
Posts: 6,793
Rep Power: 71
FMDenaro has a spectacular aura aboutFMDenaro has a spectacular aura aboutFMDenaro has a spectacular aura about
If the particle covers the computational cell You cannot solve the fluid equations there
FMDenaro is offline   Reply With Quote

Old   November 1, 2018, 15:12
Default
  #5
Senior Member
 
ali
Join Date: Jul 2016
Posts: 147
Rep Power: 9
ebtedaei is on a distinguished road
Quote:
Originally Posted by 90nash View Post
Hello Foamers,
I have a conceptual question to which i am not able to find an answer.

I am performing ONE-WAY coupled simulation of micron sized particles suspended in a turbulent flow field. The concentration of particles is low enough for me to consider only one-way coupling. i am solving the flow field using LES. The mesh cell size is generally larger than the particle size. However, near the wall, since LES requires DNS type resolution, the mesh cells are smaller than the particle dimensions. My questions:

1. For one-way coupled simulations, is it necessary to have the condition that particles must be smaller than mesh cells?

2. There must be a way to deal with the situation where DEM particles are larger than mesh cells but i could not find any reference article for it. Can someone please guide me with this.

Thanks a ton!
Dear Saini,
I have a problem similar to your problem but for two-way coupled simulation!
I have simulated the CFD step and now I want to run coupled CFD-DEM that DEM particles are larger than some mesh cells especially near wall.

What must I do? Did you find a solution?

Thank you
ebtedaei is offline   Reply With Quote

Old   November 1, 2018, 20:50
Default CFD vs PIV
  #6
New Member
 
bambang
Join Date: Jun 2018
Posts: 10
Rep Power: 8
wahonot is on a distinguished road
Hello, I am a newcomer in CFD. I have one question. What the weakness of PIV if compare to the CFD especially in in-cylinder engine flow. Thank you.
wahonot is offline   Reply With Quote

Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
[ICEM] Effect of globle mesh size and mesh independency sujay ANSYS Meshing & Geometry 20 September 29, 2019 07:36
[snappyHexMesh] crash sHM H25E OpenFOAM Meshing & Mesh Conversion 11 November 10, 2014 11:27
Inner geometry gets lost exporting mesh from ICEM CFD to CFX-Pre powpow CFX 3 December 20, 2012 09:14
critical error during installation of openfoam Fabio88 OpenFOAM Installation 21 June 2, 2010 03:01
Warning 097- AB Siemens 6 November 15, 2004 04:41


All times are GMT -4. The time now is 19:11.