Soltys, Michael听1听;听Crimaldi, John听2
1听University of Colorado
2听University of Colorado
Turbulent fluid flow plays an important role in many physical and biological mixing processes. This is exemplified by broadcast spawning, the reproductive strategy used by corals and many other marine invertebrates. Current biological models predict that the efficiency of broadcast spawning is vastly insufficient to sustain coral populations (Denny, 1988), but the existence of these animals suggests otherwise. These models rely on time-averaged processes over long timescales. Recent research on the structure of turbulent plumes has revealed that over short timescales structured filaments of high concentration form in turbulent flow before being dispersed to low concentrations at longer timescales (Crimaldi et. Koseff, 2006). This breakthrough in the understanding of turbulent flows has led to models that help explain the success of broadcast spawning and other mixing processes. In a two-dimensional model by Crimaldi et. al. (2009), it has been shown that vortex stirring helps scalars to coalesce therefore increasing their reaction rate, however until this time no laboratory procedure has been developed to confirm these findings.
This poster will present a novel two-dye planar laser induced fluorescence (PLIF) system which can be used to study the interactions between two passive scalars separated by a third passive scalar in a turbulent flow. This system uses an argon-ion and a krypton-ion laser each paired with a fluorescent dye, much like traditional PLIF systems discussed in Crimaldi (2008). A pair of high-speed cameras collect images of the plumes which are then post-processed to determine concentration fields of the individual plumes. The system will be used to better understand the processes that result in the success of broadcast spawning and other mixing phenomena.
Denny, M., 1988. Biology and the Mechanics of the Wave-Swept Environment. Princeton Univ. Press, Princeton, NJ.
Crimaldi, JP. 鈥淧lanar laser induced fluorescence in aqueous flows.鈥� EXPERIMENTS IN FLUIDS 44.6 (2008): 851-863.
Crimaldi, JP, JR Cadwell, and JB Weiss. 鈥淩eaction enhancement of isolated scalars by vortex stirring.鈥� PHYSICS OF FLUIDS 20.7 (2008). 22 Feb 2009
Crimaldi JP, Koseff JR. 2006. Structure of turbulent plumes from a momentumless source in a smooth bed. Environ Fluid Mech 6:573 鈥� 592.