Numerical Modeling of Kelvin-Helmholtz Instability

 

3D volumetric movies

Direct Numerical Simulations of
KH instability at Ri = 0.05, Re = 2,500
  

1. Mechanical and Thermal Dissipation Fields (side view)


(yellow/red is mechanical dissipation, blue is thermal dissipation)

2. Vorticity Dynamics with l_2 (side view)


3. Vorticity Dynamics with l_2 (combined views)



2D movies

A. Direct Numerical Simulations of KH instability
at Ri = 0.05, Re = 2,500 (large domain)
  

Vorticity magnitude (side view)



B. Large-Eddy Simulation of KH instability
at Ri = 0.05, Re = 10,000
  

Vorticity magnitude (side and top views)




Recent publications describing KH instability dynamics
and applications include:

Fritts, D. C., C. Bizon, J. A. Werne, and C. K. Meyer, 2003: Layering accompanying turbulence generation due to shear instability and gravity wave breaking, J. Geophys. Res., 108, D8, 8452, doi:10.1029/2002JD002406.
********** Text.PDF, Figures **********


Werne, J. T. Lund, B. A. Pettersson-Reif, P. Sullivan, and D. C. Fritts, 2005: CAP Phase II simulations for the Air Force HEL-JTO project: Atmospheric turbulence simulations on NAVO's 3000-processor IBM P4+ and ARL's 2000-processor Intel Xeon EM64T cluster, DoD HPCMO Conference, July.  ********  Paper.pdf  ***********


Franke, P. M., K. Wan, D. C. Fritts, J. Werne, and T. Lund, 2009: Computation of radar backscatter from realistic turbulence volumes, I: Radar backscatter computations and measurement biases,
J. Geophys. Res., to be submitted.

Fritts, D. C., P. Franke, K. Wan, T. Lund, and J. Werne, 2009: Computation of radar backscatter from realistic   turbulence volumes, II: Backscatter moments throughout the lifecycle of a Kelvin-Helmholtz instability,    J. Geophys. Res., to be submitted. 
********  Paper.pdf, Figures.pdf **********

Earlier publications addressing these dynamics:

Palmer, T. L., D. C. Fritts, O. Andreassen, and I. Lie, 1994:  Three-dimensional evolution of Kelvin-Helmholtz billows in stratified compressible flow, Geophys. Res. Lett., 21, 2287-2290.

Fritts, D. C., T. L. Palmer, O. Andreassen, and I. Lie, 1996:  Evolution and breakdown of Kelvin-Helmholtz billows in stratified compressible flows, I: Comparison of two- and three-dimensional flows, J. Atmos. Sci., 53, 3173-3191.

Palmer, T. L., D. C. Fritts, and O. Andreassen, 1996: Evolution and breakdown of Kelvin-Helmholtz billows in stratified compressible flows, II: Instability structure, evolution, and energetics  J. Atmos. Sci., 53, 3192-3212.

Werne, J. A., and D. C. Fritts, 1998: Turbulence in stratified and sheared fluids: T3E simulations, 8th DoD HPC User Group Symposium.

Werne, J. A., and D. C. Fritts, 1999: Stratified shear turbulence: Evolution and statistics, Geophys. Res. Lett., 26, 439-442.

Werne, J. A., and D. C. Fritts, 1999: Anisotropy in stratified shear turbulence , 9th DoD HPC User Group Symposium, Monterey, CA.

Werne, J. A., and D. C. Fritts, 2000: Structure functions in stratified shear turbulence , 10th DoD HPC User Group Symposium, Albequerque, NM.

Werne, J. A., and D. C. Fritts, 2001: Anisotropy in a stratified shear layer, Phys. Chem. Earth, 26, 263-268.

Werne, J.A., C. Bizon, and D. C. Fritts, 2001:  Wave breaking and shear turbulence simulations in support of the Airborne Laser, 11th DoD HPC User Group Symposium, Biloxi, MS.


Acknowledgments: Research described on this page was performed with support from several NSF grants and NASA, AFOSR, and MDA contracts.