# how to set y value(distance nearest to the wall) in blockMesh

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

 April 27, 2011, 07:20 how to set y value(distance nearest to the wall) in blockMesh #1 Member   Robert Ong Join Date: Aug 2010 Posts: 68 Rep Power: 8 Hi All, I've been playing around with the simpleGrading, unfortunately the y I'm after is still far compared to what I want. Another thing is I have different y values throughout my domain (inlet, outlet, bottom, etc), so do I need to average them out or just consider the highest y value in a particular domain? Thanks very much for your time and attention. Regards, Robert

 April 27, 2011, 08:47 #2 Senior Member     Roman Thiele Join Date: Aug 2009 Location: London, UK Posts: 368 Rep Power: 13 what do you mean with y value, do you mean your yPlus value? what kind of mesh are you working with? just simple blocks? __________________ ~roman

 April 27, 2011, 09:04 #3 Member   Robert Ong Join Date: Aug 2010 Posts: 68 Rep Power: 8 Hi Roman, I meant the y value (not yPlus) used in this formula yPlus=uStar*y/nu. Alternatively, you can also use this http://geolab.larc.nasa.gov/APPS/YPlus/ Yes, I am just dealing with the simple hexagonal blocks with a hemipshere object in the middle which I meshed using cellSet and setSet command after having exported it from the STL file. Thanks and regards, Robert

 April 28, 2011, 03:24 #4 Senior Member     Roman Thiele Join Date: Aug 2009 Location: London, UK Posts: 368 Rep Power: 13 you can calculate your dimension of the cell in wall direction with this yDim = r / [nCells *{ (l/s)+1} ] where r is the block length in direction of stretching, nCells, the number cells you want in this direction (l/s) is the ratio between largest an smallest cell, meaning your expansion ratio. the center will the be the y that you need for the yStar or yPlus calculation your are looking. Therefore, just divide by 2. if you think you get too many cells you can use the tool Code: `refineWallLayer` to split only the cells at the wall. __________________ ~roman

 Thread Tools 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 On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post H.P.LIU Phoenics 7 July 13, 2010 04:31 piprus OpenFOAM Installation 22 February 25, 2010 14:43 gruber2 OpenFOAM Installation 5 December 30, 2005 05:27 Michal FLUENT 6 February 13, 2001 15:49 Abhijit Tilak Main CFD Forum 6 February 5, 1999 02:16

All times are GMT -4. The time now is 16:58.