Can an inviscid flow rotational? Potential Flow?

Click For Summary
SUMMARY

The discussion centers on the relationship between viscosity and vorticity in fluid dynamics, specifically questioning whether an inviscid flow can be rotational. Participants agree that in the case of a shear flow defined by U[y] = k*y, the vorticity remains constant and non-zero regardless of viscosity. This indicates that inviscid flows can indeed be rotational, challenging the conventional understanding that vorticity arises solely from viscosity. The conversation also explores the implications of zero shear stress alongside non-zero vorticity, highlighting the complexities of fluid behavior in different flow conditions.

PREREQUISITES
  • Understanding of fluid dynamics principles
  • Familiarity with vorticity and shear flow concepts
  • Knowledge of the distinction between viscous and inviscid flows
  • Basic grasp of angular momentum in fluid systems
NEXT STEPS
  • Research the mathematical formulation of vorticity in inviscid flows
  • Study the implications of shear stress in viscous versus inviscid flows
  • Explore the concept of potential flow and its requirements
  • Investigate the behavior of Tesla turbines in relation to fluid dynamics
USEFUL FOR

Students and professionals in fluid dynamics, mechanical engineers, and anyone interested in the theoretical aspects of flow behavior and vorticity in both viscous and inviscid contexts.

hanson
Messages
312
Reaction score
0
Hi all.
It seems to me that the origin of vorticity comes from viscosity, right?
So, if a flow is inviscid, can it be rotational?

For the example of a shear flow, U[y] = k*y, the vorticity a non-zero constant, k, everywhere, right? And we actually did not consider whether the flow is viscous or not when considering this shear flow. If the flow is inviscid, the vorticity is still constant and non-zero, right? So, it seems that an inviscid flow can still be rotational, right?

So, in the shear flow case, what is the difference between having the fluid being viscous and non-viscous? If the viscosity being zero but vorticity being non-zero, that means there is angular momentum (from non-zero vorticity) but no shear stress? Since the coefficient of viscosity is zero? It seems rather non-intuitive to me...We can have a zero shear stress but non-zero vorticity or angular momentum?

Also, why a potential flow must be inviscid? can it be just irrotational? Is that a viscous flow must be rotational?

Please kindly address my confusion. Thanks.
 
Engineering news on Phys.org
Good questions and all over my head, I'll be watching for an intelligent reply. You did get me thinking about Tesla turbines at 8:30 in the morning, now I'll get nothing done the rest of the day.:cool:
 
Please help.
What is the difference between a viscous shear flow and an inviscid shear flow?
 

Similar threads

Election of cut placement for Shear flow -- Hibbeler's example
  • · Replies 1 ·
Replies
1
Views
2K
Inviscid flows and the turbulent (eddy) viscosity
  • · Replies 1 ·
Replies
1
Views
2K
Can Inviscid Flows Be Rotational?
  • · Replies 7 ·
Replies
7
Views
20K
Graduate Navier-Stokes solutions: Beltrami flow
  • · Replies 0 ·
Replies
0
Views
3K
Doublet flow in Fluid Dynamics between two spheres or cylinders
  • · Replies 0 ·
Replies
0
Views
2K
Need some intuition for laminar flow in different geometries
  • · Replies 10 ·
Replies
10
Views
3K
Undergrad Air flow between sphere/cylinder and membrane
  • · Replies 1 ·
Replies
1
Views
1K
Graduate Stressing Over Stress Tensor Symmetry in Navier-Stokes
  • · Replies 2 ·
Replies
2
Views
2K
Potential flows and Helmholtz decomposition
  • · Replies 5 ·
Replies
5
Views
2K
Graduate Potential flow, inviscid flow, incompressible flow
  • · Replies 17 ·
Replies
17
Views
4K