CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > ANSYS > CFX

Positive displacement pump moving mesh

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Search this Thread Display Modes
Old   May 29, 2016, 02:22
Default Positive displacement pump moving mesh
Join Date: Feb 2011
Posts: 37
Rep Power: 15
eng_norouzi is on a distinguished road
I am working on a positive displacement pump (piston pump) using Ansys CFX. The inlet and outlet ports are opened and closed respectively based on the movement of piston. I am using moving mesh for the entire fluid domain. The problem is that when the inlet port is completely closed an error occurs. Therefore always a small gap should exist. How can I remedy this problem? I guess I should use remeshing but I am not familiar with this process.
My case is similar to the movement of internal combustion engine which is a tutorial of CFX. In that example the outlet port is not completely closed. But this does not agree with real condition.
best regards,
eng_norouzi is offline   Reply With Quote

Old   May 29, 2016, 07:29
Super Moderator
Glenn Horrocks
Join Date: Mar 2009
Location: Sydney, Australia
Posts: 17,688
Rep Power: 143
ghorrocks is just really niceghorrocks is just really niceghorrocks is just really niceghorrocks is just really nice
There are a few possible approaches:

1) Move the valve to almost closed and stop - so never totally close the valve.
2) You can improve option 1 by putting a momentum source term on the valve curtain and when the valve is shut you use a momentum source term to stop flow.
3) You can use an interface which you can slide shut. This allows you to totally shut the valve, but you will have to change the geometry a bit to fit a sliding interface in.
4) You can move the valve to almost shut and then remesh such that you do not mesh the valve curtain so the valve is completely shut. This approach means you shut the valve a little earlier than it should, which can be offset somewhat by modifying the timing at valve closed to give a similar effective flow.

There are probably more options as well. But there is some for you to think about.
ghorrocks is offline   Reply With Quote


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
[snappyHexMesh] Error snappyhexmesh - Multiple outside loops avinashjagdale OpenFOAM Meshing & Mesh Conversion 53 March 8, 2019 09:42
[mesh manipulation] Importing Multiple Meshes thomasnwalshiii OpenFOAM Meshing & Mesh Conversion 18 December 19, 2015 18:57
Moving mesh Niklas Wikstrom (Wikstrom) OpenFOAM Running, Solving & CFD 122 June 15, 2014 06:20
[snappyHexMesh] 2D AMI Moving Mesh with sHM; How hard can this be? ADGlassby OpenFOAM Meshing & Mesh Conversion 18 June 18, 2013 06:07
Periodic displacement // Moving Mesh Badi CFX 0 April 10, 2013 07:50

All times are GMT -4. The time now is 09:27.