CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > OpenFOAM

pimpleDyMFoam - harmonic motion of a plate - wrong pressure distribution

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

LinkBack Thread Tools Search this Thread Display Modes
Old   April 30, 2014, 08:28
Default pimpleDyMFoam - harmonic motion of a plate - wrong pressure distribution
New Member
Join Date: Apr 2014
Posts: 1
Rep Power: 0
adii is on a distinguished road
Dear all,

I am working on a plate with a simple harmonic motion. This plate is located in an entirely closed box full of water. It is an axisymmetric geometry.
By using pimpleDyMFoam solver and uncoupledSixDoFRigidBodyDisplacement on the plate in the pointDisplacement file I achieved to perform the simple harmonic motion of the plate.
A picture representing the geometry and the patches is enclosed.
I also enclosed my pointDisplacement and U files.
And here is my p file :

 dimensions      [0 2 -2 0 0 0 0];

internalField   uniform 0;


        type zeroGradient;     

       type zeroGradient;

        type zeroGradient;

        type zeroGradient;    

        type zeroGradient; 

    type symmetryPlane; 

        type zeroGradient;           

        type    wedge;    


        type   wedge;  

The velocity comportment seems physical with eddies moving the way I expected (cf picture "Velocity" enclosed)

But for the pressure, my results are not correct. When the plate goes up, there is a depression on the top of the plate and an overpressure on the bottom of the plate... (you can see it on the "Pressure" picture enclosed)
And the same reversed illogical presure distribution occurs when the plate goes down.

At the previous step of my work, I made the plate moves only at an uniform velocity and the pressure distribution was totally fine.
So I guess the problem comes from the use of the uncoupledSixDoFRigidBodyDisplacement but I can't figure how to fix it to obtain a correct pressure distribution for the simple harmonic motion.

Does anyone has experienced this kind of pressure distribution problem with simple harmonic motion?

Thanks in advance,

Attached Images
File Type: png Geometry.png (48.1 KB, 19 views)
File Type: png Pressure.png (88.7 KB, 16 views)
File Type: png Velocity.png (65.0 KB, 19 views)
Attached Files
File Type: txt pointDisplacement.txt (3.7 KB, 9 views)
File Type: txt U.txt (1.6 KB, 3 views)
adii 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
Correct lift but wrong pressure drag - possible? zx Main CFD Forum 4 July 27, 2007 23:38
Pressure distribution over an airfoil-help Andrew Parker FLUENT 4 February 13, 2002 11:51
Pressure contour seems wrong??? Harry Qiu FLUENT 1 June 29, 2001 05:53
Hydrostatic pressure in 2-phase flow modeling (CFX4.2) HB &DS CFX 0 January 9, 2000 13:19
Hydrostatic pressure in 2-phase flow modeling (long) DS & HB Main CFD Forum 0 January 8, 2000 15:00

All times are GMT -4. The time now is 05:16.