[GTP] GTP MMM - Seminar at NCAR Thursday December 2, 2010

[Carolyn Mueller]

Just a reminder of tomorrow's seminar.

Carolyn Mueller
NCAR IMAGe
1850 Table Mesa Drive 
Boulder, CO 80305 
www.image.ucar.edu 
Tel: 303 497-2491
Fax: 303-497-2483



Carolyn Mueller wrote:
> Turbulent mixing and beyond: problems, concepts, solutions
>
> Snezhana I. Abarzhi
>
> University of Chicago
>
> Turbulent mixing plays an important role in a broad variety of natural 
> and artificial systems, spanning astrophysical to atomistic scales and 
> low to high energy densities. Examples include inertial confinement 
> fusion, supernovae, atmospheric and oceanic convection, non-canonical 
> boundary layers and optical free-space communications. Theoretical 
> description of non-equilibrium mixing transports is a challenging 
> problem due to singular aspects of the governing (Euler or 
> Navier-Stokes) equations. Furthermore these processes are 
> statistically unsteady and their fluctuating quantities are 
> essentially time-dependent and non-Gaussian. We apply the new 
> theoretical concept, the rate of momentum loss, to describe the 
> transports of mass, momentum and energy in turbulent mixing flow and 
> to capture its anisotropic and inhomogeneous character. It is shown 
> that invariant, scaling and spectral properties of unsteady turbulent 
> mixing differ substantially from those of isotropic and homogeneous 
> turbulence. Time- and scale-invariance of the rate of momentum loss 
> leads to non-dissipative momentum transfer, to 1/2 and 3/2 power-law 
> scale-dependencies of the velocity and Reynolds number and to 
> non-Kolmogorov spectra. Turbulent mixing exhibits more order compared 
> to isotropic turbulence, and its viscous and dissipation scales are 
> finite and set by flow acceleration. We describe the random character 
> of the unsteady turbulent flow and show that the rate of momentum loss 
> is the statistical invariant and a robust diagnostic parameter for 
> either sustained or time-dependent acceleration. Some criteria are 
> discussed for the estimate of the fidelity and information capacity of 
> the experimental and numerical data sets.
>
> December 2, 2010
> FL2 main Auditorium
> Room 1022
> Lecture 3:30 pm
>