2:00–3:00 pm
KPTC 206 5720 S Ellis Ave
Buoyancy, diffusion, and immersed solids
Solid particles in the ocean play an important role in the carbon cycle and ecosystem. The ocean is vertically stratified by density differences arising from salinity and temperature, and unique behavior emerges when solid particles interact with these fields. This talk will focus on two phenomena governed by these interactions. In the first, neutrally buoyant particles create a disturbance in a background solute gradient, driving a fluid flow. Although a single spherical particle isn’t forced by this flow, multiple particles can be attracted and held together, providing a mechanism for particle aggregation in stratified fluids as observed in the ocean. In the second, porous particles exchange mass with the stratifying solute through diffusion, causing their density to change. In a regime where the particle transport is governed by this diffusive mass exchange, smaller particles settle faster, unlike in a uniform fluid. This characterization may improve prediction and control of nutrient transport processes in the ocean.
Speaker: Dr. Robert Hunt, Brown University
Host: Prof. Heinrich Jaeger, Dept. of Physics (jaeger@uchicago.edu)