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Experimental Investigation of Secondary Flow Structures Downstream of a Model Type IV Stent Failure in a 180° Curved Artery Test Section
Published on: July 19, 2016
Energy dissipating structures produced by walls in two-dimensional flows at vanishing viscosity
Romain Nguyen van Yen1, Marie Farge, Kai Schneider
1LMD-CNRS-IPSL, École Normale Supérieure, Paris, France.
Physical Review Letters
|June 4, 2011
Summary
Numerical experiments reveal persistent energy dissipating structures in 2D incompressible flows. As a dipole impacts a wall, these structures form in a thin vorticity sheet, independent of viscosity in the limit.
Area of Science:
- Fluid dynamics
- Computational physics
Background:
- Understanding energy dissipation in fluid flows is crucial for various scientific and engineering applications.
- Incompressible flows with solid boundaries are common in nature and technology.
Purpose of the Study:
- To investigate the behavior of energy dissipation during a dipole impact with a wall in 2D incompressible flows.
- To explore the role of Reynolds number (Re) and viscosity on energy dissipation structures.
Main Methods:
- Numerical experiments were conducted simulating a dipole crashing into a wall.
- Reynolds number (Re) was varied from 985 to 7880.
- Navier boundary conditions approximated no-slip conditions, with slip length proportional to Re(-1).
Main Results:
- Energy dissipation was observed to initiate within a vorticity sheet near the wall.
- This sheet subsequently rolled into a spiral and detached from the wall.
- The integrated energy dissipation rate approached Re-independent values, suggesting persistent structures.
Conclusions:
- Energy dissipating structures exist in 2D incompressible flows near walls.
- These structures persist even as viscosity approaches zero (vanishing viscosity limit).
- The findings offer insights into fundamental fluid dynamics phenomena.
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