How to simulate a sphere moving inside a fluid region

jsb12136 · April 17, 2015, 17:40

Hi all,
I am planning to do a simulation about a sphere moving inside a fluid region. My question is, under this condition, I can not observe the fluid characteristic by using scalar scene because the sphere is inside the block

. Should I use DFBI motion with a linear spring? Thanks.

ggulgulia · April 18, 2015, 02:02

Hi Xiasong

The motion of the sphere depends on what exactly you want to simulate. If it's the motion of the sphere due to the fluid forces, then DFBi would be appropriate physics.

However, if you simply want to have the sphere moved using user defined motion, you should go for translation/translation+rotation in the motions manager under the Tools option.

Note that in both cases you'll need overset mesh.

jsb12136 · April 18, 2015, 07:53

Hi, ggulgulia
Thanks for the reply. Now I know what to do with the motion. Can you explain more about overset mesh? How can I set up a mesh that I can see trough the section. I have made a cube fluid region and the sphere is inside the cube which I can not observe. Thanks.

ggulgulia · April 18, 2015, 11:59

Hello

I really would have loved explaining overset mesh technique but the procedure is a bit lengthy and conveying it by words will lead to more confusion. I suggest you go through the tutorials that have detailed step by step demonstration to set up motion using overset mesh. They are really amazing, especially the advancements in the overset mesh incorporated in 9.06 are very useful.

April 17, 2015, 17:40	How to simulate a sphere moving inside a fluid region	#1
jsb12136 New Member Xiaosong Zhang Join Date: Oct 2014 Posts: 14 Rep Power: 11	Hi all, I am planning to do a simulation about a sphere moving inside a fluid region. My question is, under this condition, I can not observe the fluid characteristic by using scalar scene because the sphere is inside the block. Should I use DFBI motion with a linear spring? Thanks.

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April 18, 2015, 02:02		#2
ggulgulia Senior Member Gajendra Gulgulia Join Date: Apr 2013 Location: Munich Posts: 144 Rep Power: 13	Hi Xiasong The motion of the sphere depends on what exactly you want to simulate. If it's the motion of the sphere due to the fluid forces, then DFBi would be appropriate physics. However, if you simply want to have the sphere moved using user defined motion, you should go for translation/translation+rotation in the motions manager under the Tools option. Note that in both cases you'll need overset mesh.

April 18, 2015, 07:53		#3
jsb12136 New Member Xiaosong Zhang Join Date: Oct 2014 Posts: 14 Rep Power: 11	Hi, ggulgulia Thanks for the reply. Now I know what to do with the motion. Can you explain more about overset mesh? How can I set up a mesh that I can see trough the section. I have made a cube fluid region and the sphere is inside the cube which I can not observe. Thanks.

April 18, 2015, 11:59		#4
ggulgulia Senior Member Gajendra Gulgulia Join Date: Apr 2013 Location: Munich Posts: 144 Rep Power: 13	Hello I really would have loved explaining overset mesh technique but the procedure is a bit lengthy and conveying it by words will lead to more confusion. I suggest you go through the tutorials that have detailed step by step demonstration to set up motion using overset mesh. They are really amazing, especially the advancements in the overset mesh incorporated in 9.06 are very useful.