Physics Department Seminar University of Alaska Fairbanks

J O U R N A L    C L U B

Toward the characterization and understanding of turbulence and turbulent transport
David Newman
Physics Dept./Geophysical Institute

Recently, a nonlocal (quasilinear) renormalization scheme for turbulent transport of passive scalars has been formulated that allows one to derive renormalized transport equations for passive scalars in terms of fractional differential operators. As a result, this provides a method for obtaining fractional transport exponents for these problems by characterizing the statistics and correlations of the Lagrangian velocities along the characteristics trajectories of the flow. We will explore these methods to characterize tracer transport in fluid simulations of simple (drift-wave) turbulence in different physics limits. The simplified system allows us to concentrate on the role that the polarization and E X B nonlinearities play in determining the value of the effective fractional transport exponents.
In addition, we look at preliminary results from a gyro kinetic simulation that has much more physics in it to explore the characteristics of the tracer transport in that system.

(In other with turbulence simulations)

Friday, 4 May 2007
Globe Room, Elvey Building
3:45 PM