Turbulent Flow Fields / Large Eddy Simulation

Soaring attracts a remarkably diverse and talented group of people from a variety of technical fields. Maybe you are working in the subject or know someone who is. I would appreciate input in this regard.

Comments: While there is a large body of work regarding mountain wave and subsequent clear air turbulence (primarily because the scale and intensity of these events are large enough to substantially affect common and even large scale aircraft), there is a comparative paucity of detailed work in smaller scale events which are still large enough to scale according to mountain ranges, ridges, etc. A cursory examination reveals that CFD with much definition was not applied until something around the late 1980's. Progress since there does not appear to be rapid.

I have some algorithms I've developed and used to effectively in past research to predict stochastic turbulent fields and which are based on the 5/3 energy spectrum. These can be used for small scale up to medium scale integrations. NREL logarithms developed to aid in wind tunnel research might have enough flexibility to simulate large eddies in the medium to larger scale, but I'm guessing not on mountain scale very accurately.

I don't think that the RASP algorithms provide a high enough degree of resolution, but could be wrong in this regard as I don't know much about their implementation- and I am often wrong.

Once again, any help in this area would be appreciated. So as not to clog this newsgroup, please respond directly to me: gosoba at google dot com

Best Regards,

Gary Osoba

Hello Gary,

I don't know much of anything about RASP, but the base program is NCAR's WRF. I think you're correct in that resolution will limit it's application to large geographic area LES. Or maybe not. All you need is a really big computer. I do know about big computers .. but again, not much about the theoretical methods you're talking about.

Google "WRF large eddy" for some mesoscale results.

Best,
Sarah Anderson


On Friday, May 30, 2014 6:28:34 AM UTC-5, wrote:
Soaring attracts a remarkably diverse and talented group of people from a variety of technical fields. Maybe you are working in the subject or know someone who is. I would appreciate input in this regard.



Comments: While there is a large body of work regarding mountain wave and subsequent clear air turbulence (primarily because the scale and intensity of these events are large enough to substantially affect common and even large scale aircraft), there is a comparative paucity of detailed work in smaller scale events which are still large enough to scale according to mountain ranges, ridges, etc. A cursory examination reveals that CFD with much definition was not applied until something around the late 1980's. Progress since there does not appear to be rapid.



I have some algorithms I've developed and used to effectively in past research to predict stochastic turbulent fields and which are based on the 5/3 energy spectrum. These can be used for small scale up to medium scale integrations. NREL logarithms developed to aid in wind tunnel research might have enough flexibility to simulate large eddies in the medium to larger scale, but I'm guessing not on mountain scale very accurately.



I don't think that the RASP algorithms provide a high enough degree of resolution, but could be wrong in this regard as I don't know much about their implementation- and I am often wrong.



Once again, any help in this area would be appreciated. So as not to clog this newsgroup, please respond directly to me: gosoba at google dot com



Best Regards,



Gary Osoba