HR: 14:20h
AN: NG12B-03 INVITED     [PDF]
TI: Visualization Techniques in Laboratory Experiments: Resolving the Mechanics of Mixing in Complex flows
AU: * Jellinek, M
EM: markj@physics.utoronto.ca
AF: University of Toronto, Geophysical Laboratories Department of Physics, Toronto, ON M5S 1A7 Canada
AB: Many geological phenomena such as the emplacement of lava flows, the cooling and solidification of magma chambers, and the thermal evolutions of the core and mantle of the Earth involve mixing processes operating in a large range of dynamical regimes and acting over a wide range of time and length scales. Whereas turbulent stirring can play a role, say, in magma mixing processes that lead to volcanic eruptions, the compositional evolution of planetary mantles is largely due to three-dimensional (3D) unsteady laminar flow. Moreover, all such flows can involve fluids with strongly contrasting viscosities and densities. Inherent difficulties with simulating such flows numerically under appropriate conditions makes analog experiments essential to their understanding, the results of which may be incorporated into parameterized numerical models. In this talk I review some invasive and noninvasive laboratory approaches to visualizing and quantifying both the time-evolution and end result of mixing processes in complex convective flows. A particular experimental challenge is the precise resolution of 3D time-dependent overturning motions leading to mixing. Accordingly, I discuss some 2D and 3D particle image velocimetry (PIV) and particle tracking velocimetry (PTV) techniques for flow visualization that have been developed and applied to extract detailed information about the mechanics of mixing in a number of situations.
DE: 8130 Heat generation and transport
DE: 8147 Planetary interiors (5430, 5724)
DE: 8439 Physics and chemistry of magma bodies
DE: 8494 Instruments and techniques
SC: Nonlinear Geophysics [NG]
MN: 2003 Fall Meeting