# spanwise averaging for LES backward facing step

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

 July 21, 2008, 12:06 spanwise averaging for LES backward facing step #1 Sungho Yoon Guest   Posts: n/a I completed my LES calculation for a backward facing step and I'm processing the data. I want to average the data in the spanwise direction but don't know how to do it. Can anyone let me know how to do it? Sungho

 July 22, 2008, 09:37 Re: spanwise averaging for LES backward facing ste #2 Rogerio Fernandes Brito Guest   Posts: n/a I´m not sure, but you can make this on CFX-Pre, "Output Control", "Trn Stats" tab, for a transient simulation. In "Transient Statistics 1", choose "Arithmetic Average". In "Output Variables List", choose "Velocity". Do u wanna calculate the recirculation point´in the average time? I did it and my result is about 6.

 July 23, 2008, 03:16 Re: spanwise averaging for LES backward facing ste #3 Sungho Yoon Guest   Posts: n/a Thank you. I will try it. My recirculation point is about 7 based on mid span data. (experimental data indicates 6 as you predicted) I may need to refine the grid. By the way, do you think it is better to average in spanwise direction rather than just process the data at mid span? Le, Moin and Kim(1997) averaged in spanwise direction in their DNS calculation.

 July 23, 2008, 06:05 Re: spanwise averaging for LES backward facing ste #4 Sungho Yoon Guest   Posts: n/a I thoguth about it and realised that it is averaging in time rather than spanwise averaging. Thanks anyway.

 July 23, 2008, 07:54 Re: spanwise averaging for LES backward facing ste #5 Rogerio Fernandes Brito Guest   Posts: n/a So, my results were about 7.2, using a FORTRAN code in 2D dimension. I used the finite element method, using triangle elements, Galerking scheme with LES and structure function sub-grid scale model. I did an average in time for each x location. You said: "...to average in spanwise direction rather than just process the data at mid span...", I didn´t understand you, sorry, my english is bad. What does "spanwise" mean?

 July 23, 2008, 09:39 Re: spanwise averaging for LES backward facing ste #6 Sungho Yoon Guest   Posts: n/a I did a three-dimensional calculation with u(y) inlet profile. To explain in more detail, my backward facing step is generated in (x,y) coordinate but it was extended in z (spanwise) direction with periodic condition in both z boundaries. I wanted to average in z direction to get a data similar to two-dimensional calculation. Since I don't know how to do the spanwise average in a simple way, I currently process data at mid z plane only. Regards, Sungho

 July 23, 2008, 10:34 Re: spanwise averaging for LES backward facing ste #7 Rogerio Fernandes Brito Guest   Posts: n/a I understood now your problem! u have to average the componentes of your velocities in 3 directions, by the projection of the area of the element in each plane. The researches in Federal University of Uberlandia (www.ufu.br), in Brazil, probably did this type of simulation. Look for Professor Dr. Ellie Padilla or Professor Dr. Aristeu da Silveira Neto.

 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 xiuying OpenFOAM Running, Solving & CFD 8 August 27, 2013 15:33 Fluids Main CFD Forum 7 December 4, 2012 12:28 bookie56 OpenFOAM Installation 8 August 13, 2011 04:03 msrinath80 OpenFOAM Running, Solving & CFD 9 July 22, 2007 02:58 liugx212 OpenFOAM Running, Solving & CFD 3 January 4, 2006 19:07

All times are GMT -4. The time now is 15:40.