# Taylor Couette Setup and Boundary Conditions

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 August 22, 2013, 06:53 Taylor Couette Setup and Boundary Conditions #1 New Member   Danesh S Join Date: Jul 2013 Location: Bochum, Germany Posts: 27 Rep Power: 11 Hello Fellow-FOAMers, I am currently working on a setup for LES of a Taylor Couette flow. To test my setup and mesh, I start out with a laminar simulation (turbulence properties set to laminar). I want to create both laminar couette flow and laminar taylor vortex flow. I use a setup with eta = 0.5, so I have a critical Reynoldsnumber of about 78. The problem is, that I can see vortices on both ends of the cylinder for Reynolds = 50 (smaller than Re_crit) by visualising the y-compinents of velocitiy, like this: Of course for laminar couette flow, there should be no velocities in y-direction. I use icoFoam as laminar solver. Boundary conditions for p are all zeroGradient for innerWall outerWall and upper and lower end. For U all are fixedValue ( 0 0 0 ), just innerWall is rotatingWallVelocity origing (0 0 0) axis (0 1 0) omega 0.004; (rad/s, which leads to 0.002 m/s and Re = 50; viscosity 2e-5) Has anybody got an idea how to improve the setup, or why i get these vortices at low Re? Maybe cyclic BC at top and bottom are necessary? I am grateful for any kind of help! Regards, DaSh

 August 22, 2013, 06:55 #2 New Member   Danesh S Join Date: Jul 2013 Location: Bochum, Germany Posts: 27 Rep Power: 11 I have tried cyclic BC and symmetryPlane BC, which produces even worse results concerning velocity in y-direction. Has somebody got an idea, why I see y-Velocity (v) in laminar case with Re smaller Re_crit? Thanks in advance! Danesh

September 28, 2017, 12:02
Did you sort this out?
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Join Date: Feb 2013
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Quote:
 Originally Posted by DaSh I have tried cyclic BC and symmetryPlane BC, which produces even worse results concerning velocity in y-direction. Has somebody got an idea, why I see y-Velocity (v) in laminar case with Re smaller Re_crit? Thanks in advance! Danesh
Hello Danesh,

did you sort this out? I am getting Uy values for laminar Couette flow as well using simpleFoam solver..

And also why did you use "rotatingWallVelocity" on inlet BC?

Regards,

Lisandro