0
$\begingroup$

I made a 3D model and i get a numbers for the vorticity but i can't know if this numbers can used to determine if the flow is laminar or turbulent. and if yes what is the critical value of the vorticity which at it the flow became turbulent?

$\endgroup$
  • $\begingroup$ 3D model of what? How did you compute "numbers for the vorticity"? Laminar flow has vorticity in it too (consider simple shear flow for e.g.) but a turbulent flow has a very tangled three-dimensional structure of vortices in it. I recommend that you read a book like "Turbulence by P.A. Davidson" or "A first course in turbulence by Tennekes and Lumley". $\endgroup$ – Deep Apr 16 '18 at 4:00
  • $\begingroup$ the model was a 3D model of abdominal aorta, the scale of vorticity that i get in the results was from 0.0045 to 1290 $\endgroup$ – Radwa Attia Apr 17 '18 at 22:46
  • $\begingroup$ Usually biological flows are laminar. Determine the Reynolds number of the flow and compare with the critical Reynolds number for similar flows (perhaps pulsatile flow) in similar geometry (a pipe, flexible pipe, collapsible tubes) to determine whether the flow is turbulent. Vorticity numbers alone aren't of much help. The reason is that even if there is only one vortex-tube, vorticity being inversely proportional to cross-sectional area of the tube, vorticity can change drastically along the tube due to changes in area. $\endgroup$ – Deep Apr 18 '18 at 3:56
  • $\begingroup$ Maybe you can post a picture of the velocity field. If the flow field contains eddies ranging over various sizes then you may be able to call the flow turbulent. But being biological flow I would bet it's laminar. $\endgroup$ – Deep Apr 18 '18 at 3:56

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Browse other questions tagged or ask your own question.