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

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.

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.

Sorry, my mistake, the centerline velocity is 1.0 m/s.

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.