shrinking of a tube

ft2 · October 5, 2018, 06:25

hello,
i have a problem and i cannot find a solution: i would like to shrink a tube in a dynamic way in fluent.
the pipe has a inner diamiter of 2mm and a lenght of 4mm. i want to obtain a diameter of 0.01 mm and then return to the original geometry in a dynamic way. i would like a continue continuous cycle of shrinking and regaining the initial geometry.

could you please help me?

Leonardo.flores · October 17, 2018, 04:01

Wow, that's too much for me. I would try a long pipe with different sections.

RaiderDoctor · October 19, 2018, 10:28

Conceptually, I think you have at least two options:

Use a UDF to induce mesh motion along the wall of your pipe that will contract and expand. The motion will be controlled by an equation that you will have to derive, and the coding can get a bit tricky.
Simulate a 1-way FSI in which the motion is driven by Mechanical, and Fluent just solves for the flow. This, while not difficult to setup, can get very advanced, so make sure you do your research and download some tutorials.

Good luck!
RD

October 5, 2018, 06:25	shrinking of a tube	#1
ft2 New Member FT Join Date: Oct 2018 Posts: 1 Rep Power: 0	hello, i have a problem and i cannot find a solution: i would like to shrink a tube in a dynamic way in fluent. the pipe has a inner diamiter of 2mm and a lenght of 4mm. i want to obtain a diameter of 0.01 mm and then return to the original geometry in a dynamic way. i would like a continue continuous cycle of shrinking and regaining the initial geometry. could you please help me?

October 19, 2018, 10:28		#3
RaiderDoctor Senior Member Join Date: Dec 2016 Posts: 152 Rep Power: 10	Conceptually, I think you have at least two options: Use a UDF to induce mesh motion along the wall of your pipe that will contract and expand. The motion will be controlled by an equation that you will have to derive, and the coding can get a bit tricky. Simulate a 1-way FSI in which the motion is driven by Mechanical, and Fluent just solves for the flow. This, while not difficult to setup, can get very advanced, so make sure you do your research and download some tutorials. Good luck! RD

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
HLL Riemann Shock Tube Matlab Problem	Luke F	Main CFD Forum	2	May 20, 2016 02:10
double tube heat exchanger	mehyan	CFX	4	December 8, 2015 16:44
[OpenFOAM] Tube filter in Paraview	werweisswas	ParaView	0	December 10, 2012 06:18
[Other] How to set up a dynamic mesh for a piston moving through a tube of variable diameter?	karkar	OpenFOAM Meshing & Mesh Conversion	0	July 4, 2012 06:54
Tube inside a tube simulation	Rashmichem	Main CFD Forum	0	December 14, 2010 01:52

October 17, 2018, 04:01		#2
Leonardo.flores Member Leonardo Join Date: Nov 2017 Posts: 37 Rep Power: 8	Wow, that's too much for me. I would try a long pipe with different sections.