Dear,

I need to do a calculation of the dispersion of droplet carried with the wind on a flat field, no buildings around. I am not sure how to set the boundary conditions of the wind.

Is there any general accepted velocity profile of the wind?

Is there any standard for setting k and epsilon.

What about the wall boundary conditions at the ground, can it be regarded as a smooth wall , or is it common to change the roughness.

I want to focus on the flow from ground and up to around 8 meters. How fare away should I set the upper boundary conditions 100m?? and what kind, pressure boundary ?

Any help and/or link will be appreciated, Thanks Anders

Hi Anders,

information on the velocity profile (it is a logarithmic one up to a heigt of about 100-200m or even higher, depending on stratification) and turbulence properties can be found in the book "Atmospheric Turbulence" by H.A. Panofsky and J.A. Dutton.

Regards,

-Thomas