Non-positive volumes

KPraveen · June 22, 2015, 08:42

When I read the mesh , i get this warning: non-positive elements exist.

Please help

pakk · June 22, 2015, 08:53

What do you want help with?
What is not clear to you?
The error message you get seems clear to me, I don't understand which part you don't get.

KPraveen · June 22, 2015, 08:58

how can I remove these non positive volumes??

pakk · June 22, 2015, 08:59

In the meshing program that you used. Something went wrong in meshing.

KPraveen · June 22, 2015, 09:07

I am using ICEM. I tried smoothing the mesh. But I keep on getting the same problem

pakk · June 22, 2015, 09:16

I am not experienced in Icem.
But probably it has some option to show cell sizes. And you have to fix the parts that have negative cell sizes. But you are in the Fluent forum; this is not a Fluent problem but an ICEM problem, so maybe you should ask in the ICEM forum?

linh nguyen · June 22, 2015, 09:50

I think 2 problems might happened:
1) The mesh around the body did not deform. You can change the option in dynamic mesh options.
2) Your time step size is too big, hence, the movement of your body is bigger than rate of deformation of the mesh.

When the dynamic mesh appear, that should be something wrong with you mesh or mesh setup. I do not recommend you fix your negative mesh domain

Hope it helps

pakk · June 22, 2015, 09:55

Is KPraveen using a dynamic mesh? That would have been relevant information to mention in his first post...

June 22, 2015, 08:42	Non-positive volumes	#1
KPraveen New Member Praveen Join Date: Jun 2015 Posts: 8 Rep Power: 11	When I read the mesh , i get this warning: non-positive elements exist. Please help

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June 22, 2015, 08:53		#2
pakk Senior Member Join Date: Nov 2013 Posts: 1,965 Rep Power: 27	What do you want help with? What is not clear to you? The error message you get seems clear to me, I don't understand which part you don't get.

June 22, 2015, 08:58		#3
KPraveen New Member Praveen Join Date: Jun 2015 Posts: 8 Rep Power: 11	how can I remove these non positive volumes??

June 22, 2015, 08:59		#4
pakk Senior Member Join Date: Nov 2013 Posts: 1,965 Rep Power: 27	In the meshing program that you used. Something went wrong in meshing.

June 22, 2015, 09:07		#5
KPraveen New Member Praveen Join Date: Jun 2015 Posts: 8 Rep Power: 11	I am using ICEM. I tried smoothing the mesh. But I keep on getting the same problem

June 22, 2015, 09:16		#6
pakk Senior Member Join Date: Nov 2013 Posts: 1,965 Rep Power: 27	I am not experienced in Icem. But probably it has some option to show cell sizes. And you have to fix the parts that have negative cell sizes. But you are in the Fluent forum; this is not a Fluent problem but an ICEM problem, so maybe you should ask in the ICEM forum?

June 22, 2015, 09:50		#7
linh nguyen New Member Linh Tuan The Nguyen Join Date: Nov 2012 Posts: 9 Rep Power: 14	I think 2 problems might happened: 1) The mesh around the body did not deform. You can change the option in dynamic mesh options. 2) Your time step size is too big, hence, the movement of your body is bigger than rate of deformation of the mesh. When the dynamic mesh appear, that should be something wrong with you mesh or mesh setup. I do not recommend you fix your negative mesh domain Hope it helps

June 22, 2015, 09:55		#8
pakk Senior Member Join Date: Nov 2013 Posts: 1,965 Rep Power: 27	Is KPraveen using a dynamic mesh? That would have been relevant information to mention in his first post...