Moving PIPE

Martin_Sz · November 6, 2014, 07:49

Hello everyone,
I have to make a moving pipe into fluid domain. Can anyone help how to model
this problem. Do you have any tutorials which will help to make this problem?
Visualisation of this problem is on attachment.
Best regards

ghorrocks · November 6, 2014, 17:02

Why are you modelling the pipe? This sounds like a simple moving mesh simulation.

Martin_Sz · November 7, 2014, 02:29

I need to simulate heat transfer on moving pipe . I must make boolean operation (substract) on fluid domain to make interfaces between pipe and fluid domain ??On the sources I define a move of the pipe ? This is my first time to simulite moving parts in cfx. Earlier I only simulate immersed solid
Have You any tutorials or any links for similar simulations ?
Best regards

ghorrocks · November 7, 2014, 05:23

CFX comes with a number of tutorial examples on moving mesh.

In this case I would start with just a moving mesh simulation of the fluid domain to get that motion working and the flow correct. Once that is working then add the solid domain and its motion.

Note that this simulation will only work on CFX V15. You need to have motion in a solid to do this and V15 was the first version to support this.

Martin_Sz · November 7, 2014, 06:32

hello Glen
Can You give me a title of moving mesh tutorial which I could start first
Sorry for my poor english
Best regards

ghorrocks · November 8, 2014, 05:12

"Modeling a Ball Check Valve using Mesh Deformation and the CFX Rigid Body Solver"
"Oscillating Plate with Two-Way Fluid-Structure Interaction"
"Modeling a Gear Pump using an Immersed Solid" (This one is actually immersed solids but is very useful to know as an alternate approach)
"Modeling a Buoy using the CFX Rigid Body Solver"

Martin_Sz · November 12, 2014, 09:26

Hello Glenn,
I have another question for this problem.
This tutorials which You wrote on the last post are for immersed moving parts.
All these parts on t = 0 s are on the fluid. On my problem on t= 0 s pipe haven't got any connection with fluid. I define velocity on pipe 0.2 m/s and on the next delta t pipe going into fluid. How to define connections between these two domains?
I need to make cooling process for this moving pipe on the fluid domain.
Do i must make a boolean operation on fluid domain (substract area equal of pipe diameter)?
Best regards

ghorrocks · November 12, 2014, 17:53

Quote:

This tutorials which You wrote on the last post are for immersed moving parts.

Incorrect. The only one which uses immersed solids is the third (as I mentioned in the post). The other 3 use mesh motion. These tutorials will give you an introduction of how to do it.

Martin_Sz · November 13, 2014, 02:48

I know Glenn,
I wanted to say that on the all of these tutorials on time (for example) t = 0 s or on initial boundary conditions (steady state) all moving parts are on fluid domain.
In my case pipe on time t = 0 s hasn't got any contact with fluid domain.
Best regards

ghorrocks · November 13, 2014, 04:23

When the tube advances into the domain does it stop somewhere or does it go until it hits the other wall?

Martin_Sz · November 13, 2014, 04:44

Pipe passes through the entire domain . There are no collision on pipe way.

ghorrocks · November 13, 2014, 18:23

Your image shows a wall which the pipe will hit eventually. Does the pipe pass through this wall? Or is the far wall a long way away? Can you post some images of what you expect the pipe to do.

This is important as it will affect the way you model this.

Martin_Sz · November 14, 2014, 02:48

I post below explanation of my problem

ghorrocks · November 14, 2014, 05:15

OK, thanks for the clarification. The way to model this is obvious now. Have a look at the quick drawing I have done.

Put the tube in a solid domain (domain 1). Put the tube inside a long cylinder, long enough to enclose the entire motion of the tube (this is domain 2). And cut a tube out of the box for domain 2 to slide through (this is domain 3).

Domain 3 is a fluid domain, stationary mesh with a transient rotor stator GGI interface. Domain 2 is a fluid domain, moving mesh with a TRS GGI to domain 3 and a static solid/fluid GGI to domain 1. Domain 3 is a moving mesh solid domain with a static solid/fluid GGI to domain 2.

Then move the mesh of domain 2 and 3 to generate the translational motion of the tube.

Martin_Sz · November 14, 2014, 05:44

pipe is empty inside. This is not a tube, this is a pipe
will there be a difference if this is a pipe ??
Below is a schematic cross section of pipe .

ghorrocks · November 14, 2014, 07:14

That does not change anything. Just means the solid domain is a tube and the translating fluid domain (2) has a bit which includes the inside of the tube.

Martin_Sz · November 14, 2014, 07:33

Thanks a lot Glenn,
I try your method and reply ASAP
Best regards from Poland

Martin_Sz · November 20, 2014, 04:15

Quote:

Originally Posted by ghorrocks

OK, thanks for the clarification. The way to model this is obvious now. Have a look at the quick drawing I have done.

Put the tube in a solid domain (domain 1). Put the tube inside a long cylinder, long enough to enclose the entire motion of the tube (this is domain 2). And cut a tube out of the box for domain 2 to slide through (this is domain 3).

Domain 3 is a fluid domain, stationary mesh with a transient rotor stator GGI interface. Domain 2 is a fluid domain, moving mesh with a TRS GGI to domain 3 and a static solid/fluid GGI to domain 1. Domain 3 is a moving mesh solid domain with a static solid/fluid GGI to domain 2.

Then move the mesh of domain 2 and 3 to generate the translational motion of the tube.

Hello Glenn
Can You describe in more detail ?
Best regards

ghorrocks · November 20, 2014, 05:48

Which bit don't you understand?

Martin_Sz · November 20, 2014, 06:06

1 ) on frame change/mixing model (on interface) i choose option transient rotor stator.?
2) domain 2 (on Your drawing) is moving domain ?
3) domain 1 and 3 are stationary domains?
4) solid domain have a defined solid motion on solid models option?
5) which domains have turn on mesh deformation?
6) on the interface (on fluid domain) which options i need to define ??
Best regards

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November 6, 2014, 17:02		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	Why are you modelling the pipe? This sounds like a simple moving mesh simulation.

November 7, 2014, 02:29		#3
Martin_Sz Senior Member Marcin Join Date: May 2014 Location: Poland, Swiebodzin Posts: 313 Rep Power: 13	I need to simulate heat transfer on moving pipe . I must make boolean operation (substract) on fluid domain to make interfaces between pipe and fluid domain ??On the sources I define a move of the pipe ? This is my first time to simulite moving parts in cfx. Earlier I only simulate immersed solid Have You any tutorials or any links for similar simulations ? Best regards

November 7, 2014, 05:23		#4
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	CFX comes with a number of tutorial examples on moving mesh. In this case I would start with just a moving mesh simulation of the fluid domain to get that motion working and the flow correct. Once that is working then add the solid domain and its motion. Note that this simulation will only work on CFX V15. You need to have motion in a solid to do this and V15 was the first version to support this.

November 7, 2014, 06:32		#5
Martin_Sz Senior Member Marcin Join Date: May 2014 Location: Poland, Swiebodzin Posts: 313 Rep Power: 13	hello Glen Can You give me a title of moving mesh tutorial which I could start first Sorry for my poor english Best regards

November 8, 2014, 05:12		#6
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	"Modeling a Ball Check Valve using Mesh Deformation and the CFX Rigid Body Solver" "Oscillating Plate with Two-Way Fluid-Structure Interaction" "Modeling a Gear Pump using an Immersed Solid" (This one is actually immersed solids but is very useful to know as an alternate approach) "Modeling a Buoy using the CFX Rigid Body Solver"

November 12, 2014, 09:26		#7
Martin_Sz Senior Member Marcin Join Date: May 2014 Location: Poland, Swiebodzin Posts: 313 Rep Power: 13	Hello Glenn, I have another question for this problem. This tutorials which You wrote on the last post are for immersed moving parts. All these parts on t = 0 s are on the fluid. On my problem on t= 0 s pipe haven't got any connection with fluid. I define velocity on pipe 0.2 m/s and on the next delta t pipe going into fluid. How to define connections between these two domains? I need to make cooling process for this moving pipe on the fluid domain. Do i must make a boolean operation on fluid domain (substract area equal of pipe diameter)? Best regards

November 13, 2014, 02:48		#9
Martin_Sz Senior Member Marcin Join Date: May 2014 Location: Poland, Swiebodzin Posts: 313 Rep Power: 13	I know Glenn, I wanted to say that on the all of these tutorials on time (for example) t = 0 s or on initial boundary conditions (steady state) all moving parts are on fluid domain. In my case pipe on time t = 0 s hasn't got any contact with fluid domain. Best regards

November 13, 2014, 04:23		#10
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	When the tube advances into the domain does it stop somewhere or does it go until it hits the other wall?

November 13, 2014, 04:44		#11
Martin_Sz Senior Member Marcin Join Date: May 2014 Location: Poland, Swiebodzin Posts: 313 Rep Power: 13	Pipe passes through the entire domain . There are no collision on pipe way.

November 13, 2014, 18:23		#12
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	Your image shows a wall which the pipe will hit eventually. Does the pipe pass through this wall? Or is the far wall a long way away? Can you post some images of what you expect the pipe to do. This is important as it will affect the way you model this.

November 14, 2014, 07:14		#16
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	That does not change anything. Just means the solid domain is a tube and the translating fluid domain (2) has a bit which includes the inside of the tube.

November 14, 2014, 07:33		#17
Martin_Sz Senior Member Marcin Join Date: May 2014 Location: Poland, Swiebodzin Posts: 313 Rep Power: 13	Thanks a lot Glenn, I try your method and reply ASAP Best regards from Poland

November 20, 2014, 05:48		#19
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	Which bit don't you understand?

November 20, 2014, 06:06		#20
Martin_Sz Senior Member Marcin Join Date: May 2014 Location: Poland, Swiebodzin Posts: 313 Rep Power: 13	1 ) on frame change/mixing model (on interface) i choose option transient rotor stator.? 2) domain 2 (on Your drawing) is moving domain ? 3) domain 1 and 3 are stationary domains? 4) solid domain have a defined solid motion on solid models option? 5) which domains have turn on mesh deformation? 6) on the interface (on fluid domain) which options i need to define ?? Best regards