CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   Main CFD Forum (http://www.cfd-online.com/Forums/main/)
-   -   IMPINGING JET PROBLEM (http://www.cfd-online.com/Forums/main/479-impinging-jet-problem.html)

Chuck Leakeas January 21, 1999 14:46

IMPINGING JET PROBLEM
 
I have some questions about a circular impinging jet problem that I am working on. Here it is:

I have a axisymmetric jet in which the Reynolds number inside the jet is 93, and the velocity profile given is for a laminar flow. When the flow leaves the nozzle and expands normally into a wall some distance away will the entire flow field still be laminar, or is there a chance that there may be some turbulence generated? If so, how would I know that there is turbulence?

Any comments or suggestions would be greatly appreciated. Thanks in advance.

Chuck

Achuth Rao January 22, 1999 09:21

Re: IMPINGING JET PROBLEM
 
Is your jet impinging on to a wall or expanding in free space. Are you interested in cfd or experiments.

If the jet is impinging against a wall then depending on the distance between the nozzle and the wall it could develope disturbances which could make it turbulent.

Chuck Leakeas January 22, 1999 12:56

Re: IMPINGING JET PROBLEM
 
Thanks for the response Achuth, actually I am numerically modeling this problem. The Reynolds number inside the jet is 93 with a fully developed and laminar velocity profile. The centerline velocity is 100 m/s while the impinging surface is located 4 nozzle diameters away from the nozzle exit. Is there anyway to say for sure if there is turbulence generated near the impinging surface? Any comments would be greatly appreciated.

Chuck Leakeas January 23, 1999 01:19

Re: IMPINGING JET PROBLEM
 
Sorry, my mistake, the centerline velocity is 1.0 m/s.

John C. Chien January 29, 1999 18:43

Re: IMPINGING JET PROBLEM
 
The formation of the shear layer is relatively unstable because of the profile shape and the growth of the shear layer. So, you may want to look into this area more closely.


All times are GMT -4. The time now is 09:00.