In a distance above the ground, my LES result is not good

panda60 · January 22, 2010, 05:03

Dear foamers:

I am confused by my LES result. My simulation is a wind engineering problem. I use Smagorinsky model with Van Driest damping function, and Wall function the same time. Through my compration along a horizontal line behind building, my result is good near building, but smaller and smaller farer from building.

Who khows why like this ?
my simulation dt=5e-5, now the interation steps is about 60000 steps, total time is 3 second. Although the total time is not enough ,but I think my result has problem, compared to RANS result and experiment data.

panda60 · January 22, 2010, 05:19

my comparetion is along AB line. in the weak region behind building ,The LES result is good ,bu why it is not good far from building ? my positon is near ground ,if it is affected by wall function ? or by my symmetry side boundary?

AirS · January 22, 2010, 08:52

Hi panda60,
why are you using both the VanDriest damping and wall functions ?

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January 22, 2010, 05:19		#2
panda60 Senior Member Jiang Join Date: Oct 2009 Location: Japan Posts: 186 Rep Power: 17	my comparetion is along AB line. in the weak region behind building ,The LES result is good ,bu why it is not good far from building ? my positon is near ground ,if it is affected by wall function ? or by my symmetry side boundary?

January 22, 2010, 08:52		#3
AirS Member Join Date: Sep 2009 Posts: 45 Rep Power: 17	Hi panda60, why are you using both the VanDriest damping and wall functions ?