Experimental investigation of mixing in a stratified fluid due to diffusion-driven flows in a loosely-packed particle layer

An experimental study was undertaken to investigate if a loosely-packed particle layer can induce mixing due to diffusion-driven Phillips-Wunsch boundary flows in a quiescent stratified fluid. Diffusion-driven flows can exist along a sloped boundary in a fluid with a density gradient that varies with height, so these flows will also exist along the curved surface of a spherical boundary. A particle layer was created using 6.35 mm diameter Polystyrene spheres in a salt-stratified fluid. A linear density stratification was pumped into an acrylic tank from below using a double-bucket system. A calibrated salinity probe, mounted on a computer-controlled traverse, was used to measure the evolution of the density profile in the tank over time. The results of the density profiles showed a measurable change in the density profile in the tank over several weeks. The density profile in the area vertically adjacent to the particle layer was nonlinear due to mixing induced by the Phillips-Wunsch boundary flows created by the spherical particles.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Etheridge, William B. (William Bruce)

Advisor dc:contributor.advisor

• Thomas Peacock.

• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/40426

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/40426