
[Sponsors] 
July 3, 2012, 09:23 
interFoam with centrifugal Force

#1  
New Member
Matthias P
Join Date: May 2010
Posts: 16
Rep Power: 7 
Dear Foamers,i try to simulate the development of a liquid parabola in a cylinder which is filled with water by one third. The other part is captured with air. For regarding the rotation of the fluid i included the centrifugal force in the solver interFoam like it is shown below.
Quote:


January 24, 2013, 06:11 

#2 
Member
Join Date: May 2012
Posts: 55
Rep Power: 6 
Hello MatP,
I think the formula in your Ueqn() is wrong. Why did you add rad_ ? How did you define rad_ and omega_? Last edited by styleworker; January 24, 2013 at 11:13. 

January 24, 2013, 12:30 

#3 
Member
Join Date: May 2012
Posts: 55
Rep Power: 6 
Actually I just have a little difference between MRFInterFoam and interFoam including centrifugal force for steady state and moderate angular velocities.
Modified UEqn: Code:
fvVectorMatrix UEqn ( fvm::ddt(rho, U) + fvm::div(rhoPhi, U)  fvm::laplacian(muEff, U)  (fvc::grad(U) & fvc::grad(muEff)) //+ Fcent + (rho*((2.0*M_PI/60.0*omega_vector)^((2.0*M_PI/60.0*omega_vector)^mesh.C()))) //omega_vector[1/s] in [rad/m] // fvc::div(muEff*(fvc::interpolate(dev(fvc::grad(U))) & mesh.Sf())) ); Code:
dimensionedVector omega_vector(twoPhaseProperties.lookup("omega_vector")); Code:
omega_vector omega_vector [ 0 0 1 0 0 0 0 ] (0 0 5); 

March 30, 2013, 14:14 

#4 
New Member
Eric Dalmau
Join Date: Mar 2013
Location: Catalonia
Posts: 20
Rep Power: 4 
Thanks a lot for your info styleworker, it was so helpful for my case. I had to add the centrifugal force to MRFInterFoam.


March 13, 2014, 22:39 

#5  
Senior Member
Huang Xianbei
Join Date: Sep 2013
Location: CAU,China
Posts: 277
Rep Power: 5 
Quote:
I tried your method, but the code can't be successfully compiled. Code:
omega^(omega^mesh.C()) Code:
omega omega [ 0 0 1 0 0 0 0 ] ( 0 0 0.01335 ); Code:
dimensionedVector omega ( transportProperties.lookup("omega") ); 

March 14, 2014, 03:54 

#6 
Member
Join Date: May 2012
Posts: 55
Rep Power: 6 
Without any error message, we can't give you an advice.
If you have just inserted this peace of code in your equation, your dimensions probably don't match. The dimension of the in the UEqn should be [kg/m^2s^2], because it is a volume force [N/m^3]. Your volume force should be implemented like this: Code:
fvVectorMatrix UEqn ( fvm::ddt(rho, U) + fvm::div(rhoPhi, U)  fvm::laplacian(muEff, U)  (fvc::grad(U) & fvc::grad(muEff)) + (rho*(omega ^ (omega ^ mesh.C()))) //Centrifugal Acceleration ); 

March 14, 2014, 07:48 

#7  
Senior Member
Huang Xianbei
Join Date: Sep 2013
Location: CAU,China
Posts: 277
Rep Power: 5 
Quote:
Thank you, but my UEqn is without rho, just looks like fvm::ddt(U), so this is no the exact reason. I have solved this problem by identify the centrifugal force as a vector field, so this works well. 

March 25, 2015, 12:16 

#8 
Member
Join Date: May 2012
Posts: 55
Rep Power: 6 
I've got a private message concerning this topic. In more recent releases of interFoam transportProperties isn't initiated explicitly in createFields.H.
Therefore this code snippet has to be implemented before dimensionedVector omega is set: Code:
IOdictionary transportProperties ( IOobject ( "transportProperties", runTime.constant(), mesh, IOobject::MUST_READ, IOobject::NO_WRITE ) ); 

Thread Tools  
Display Modes  


Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
ActuatorDiskExplicitForce in OF2.1. Help  be_inspired  OpenFOAM Programming & Development  8  July 3, 2014 10:54 
Problem with centrifugal force  norger  FLUENT  1  October 12, 2011 01:55 
Force can not converge  colopolo  CFX  13  October 4, 2011 22:03 
cyclone separator centrifugal force  kumar  FLUENT  2  May 29, 2008 03:33 
MRFZonesC questions what is the mesh_V and why only Coriolis force no centrifugal force  waynezw0618  OpenFOAM Running, Solving & CFD  49  April 8, 2008 04:23 