Polyhedra and sliding mesh?

rockewan · March 27, 2009, 18:30

I am doing some simulation in mixing tank using FLUENT. Because the impeller is a close clearance impeller, it has very small gap between the impeller and the tank wall. The impeller blades are quite thin too. All these create a lot of trouble for grid generation. Usually, there would be a couple of grids have a skewness of higher than 0.9 (less than 0.95, though), and a dozen of grids higher than 0.85. Using smaller mesh size doesn't really help reducing the skewness. If I run sliding mesh method on this mesh, usually there would be some convergence problem sooner or later, probably due to the left-handed faces created during the movement of the rotating zone. I tried converting the whole domain to polyhedra mesh. It would run fine and much faster because of much less grids. However, I found that the velocity profile is not physically reasonable on the interface between the rotating zone and the stationary zone. So I was wandering whether I could use polyhedra with sliding mesh, is there any compatability problem? It is also welcome if anyone know how to reduce the skewness effectively without using too much grids. I am already getting about 2 million grids at the moment.

P.S.: I checked the FLUENT user's guide on the polyhedra limitations. It does not say anything on sliding mesh or MRF. FLUENT model compatibility chart didn't say anything about polyhedra mesh either.

panda · March 28, 2009, 19:10

Currently, polyhedral mesh cannot be used in any moving or sliding mesh model

Freeman · March 29, 2009, 12:31

I agree with panda, Fluent user guide is clear at this point: for now, no capability for sliding mesh with polyhedra mesh

...

Greetings,

Freeman

Monker1980 · July 3, 2009, 05:36

Could either of you point me to where in the user guide it says that the polyhedral approach can't be used with sliding meshes? I can only find reference to deforming/dynamic meshes, not sliding meshes.

sheikh nasir · February 21, 2012, 07:00

hello
i am not able to apply sliding mesh in train moving in tunnel. can any body help me.
my email sheikhnasir39@gmail.com
thanks

LUMBERJACK17 · December 1, 2018, 20:07

u need to set the interfaces as non sharing faces, then it will let you create a non conformal interface, thats the thing with sliding mesh

March 27, 2009, 18:30	Polyhedra and sliding mesh?	#1
rockewan New Member Ewan Join Date: Mar 2009 Posts: 3 Rep Power: 17	I am doing some simulation in mixing tank using FLUENT. Because the impeller is a close clearance impeller, it has very small gap between the impeller and the tank wall. The impeller blades are quite thin too. All these create a lot of trouble for grid generation. Usually, there would be a couple of grids have a skewness of higher than 0.9 (less than 0.95, though), and a dozen of grids higher than 0.85. Using smaller mesh size doesn't really help reducing the skewness. If I run sliding mesh method on this mesh, usually there would be some convergence problem sooner or later, probably due to the left-handed faces created during the movement of the rotating zone. I tried converting the whole domain to polyhedra mesh. It would run fine and much faster because of much less grids. However, I found that the velocity profile is not physically reasonable on the interface between the rotating zone and the stationary zone. So I was wandering whether I could use polyhedra with sliding mesh, is there any compatability problem? It is also welcome if anyone know how to reduce the skewness effectively without using too much grids. I am already getting about 2 million grids at the moment. P.S.: I checked the FLUENT user's guide on the polyhedra limitations. It does not say anything on sliding mesh or MRF. FLUENT model compatibility chart didn't say anything about polyhedra mesh either.

February 21, 2012, 07:00	sliding mesh , plz help	#5
sheikh nasir Member Join Date: Jan 2012 Posts: 58 Rep Power: 14	hello i am not able to apply sliding mesh in train moving in tunnel. can any body help me. my email sheikhnasir39@gmail.com thanks

March 28, 2009, 19:10		#2
panda Member Join Date: Mar 2009 Posts: 35 Rep Power: 17	Currently, polyhedral mesh cannot be used in any moving or sliding mesh model

March 29, 2009, 12:31		#3
Freeman New Member Join Date: Mar 2009 Posts: 29 Rep Power: 17	I agree with panda, Fluent user guide is clear at this point: for now, no capability for sliding mesh with polyhedra mesh ... Greetings, Freeman

July 3, 2009, 05:36		#4
Monker1980 New Member Join Date: Jul 2009 Posts: 7 Rep Power: 17	Could either of you point me to where in the user guide it says that the polyhedral approach can't be used with sliding meshes? I can only find reference to deforming/dynamic meshes, not sliding meshes.

December 1, 2018, 20:07		#6
LUMBERJACK17 New Member jose antonio guzman santana Join Date: Dec 2017 Posts: 7 Rep Power: 9	u need to set the interfaces as non sharing faces, then it will let you create a non conformal interface, thats the thing with sliding mesh