Dispersal passive tracer

In whichever approach, the common denominator of most operations in stirred vessels is the common notion that the rate e of dissipation of turbulent kinetic energy is a reliable measure for the effect of the turbulent-flow characteristics on the operations of interest such as carrying out chemical reactions, suspending solids, or dispersing bubbles. As this e may be conceived as a concentration of a passive tracer, i.e., in terms of W/kg rather than of m2/s3, the spatial variations in e may be calculated by means of a usual transport equation. 

Figure 8.6 Convective dispersal of a passive tracer located at t=0 inside the circle in the upper right corner by the velocity field described by equations (8.3.11).

Britter, R.E., Caton, F., Di Sabatino, S., Cooke, K.M., Simmonds, P.G., and Nickless, G. (2000) Dispersion of a passive tracer within and above an urban canopy. In Proceedings of the Third Symposium on the Urban Environment, American Meteorological Society. 

V. Artale, G. Boffetta, A. Celani, M. Cencini, and A. Vulpiani. Dispersion of passive tracers in closed basins Beyond the diffusion coefficient. Phys. Fluids, 9 3162-3171, 1997. 

M.C. Jullien, P. Castiglione, and P. Tabeling. Experimental observation of Batchelor dispersion of passive tracers. Phys. Rev. Lett., 85 3636, 2000. 

Taylor dispersion phenomenon in microchannel consists of dispersion of a passive tracer in the flow. The schematic of a Taylor dispersion problem is shown in Figure 4.6. 

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