# Y+ and negative cell volume

 User Name Remember Me Password
 Register Blogs Members List Search Today's Posts Mark Forums Read

 December 26, 2006, 06:41 Y+ and negative cell volume #1 Ashok kumar Guest   Posts: n/a Can anyone give me a clear definition on y+ and negative cell volume. Ashok

 December 26, 2006, 18:03 Re: Y+ and negative cell volume #2 hugo Guest   Posts: n/a y+ is the adimensional normal distance from de wall y+ = f(rho, mu, tao_w, y) rho, density (kg/m^3) mu, viscosity (kg/s*m) tao_w, shear strain in the wall (kg/s^2*m) y , normal distance from de wall (m) y+ = sqrt(rho*tao_w)*y/mu for example the transition from de sub-viscous layer to the logaritmic velocity profile near the wall is when y+ is near 11 if you want to define the sub-viscous layer you need y+ for the first node close 1, if you want to use wall function, maybe with y+ for the first node close to 20 is ok A negative cell volume is not good, you need to check the mesh, I don't now how fluent calculate the negative volume but I sure that it's wrong. good luck happy new year

 Thread Tools Search this Thread Search this Thread: Advanced Search Display Modes Linear Mode

 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 OffTrackbacks are Off Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post AlmostSurelyRob OpenFOAM 3 June 24, 2011 13:06 balkrishna OpenFOAM Pre-Processing 0 August 17, 2010 02:39 [blockMesh] BlockMesh FOAM warning gaottino OpenFOAM Meshing & Mesh Conversion 7 July 19, 2010 14:11 [blockMesh] Axisymmetrical mesh Rasmus Gjesing (Gjesing) OpenFOAM Meshing & Mesh Conversion 10 April 2, 2007 14:00 AB Siemens 6 November 15, 2004 04:41

All times are GMT -4. The time now is 04:00.

 Contact Us - CFD Online - Privacy Statement - Top