Boundary-layer analysis and measurement of Newtonian and non-Newtonian fluids

The velocity fields around a circular cylinder in a crossflow of drag-reducing polymeric solutions and water were experimentally investigated using a laser-Doppler velocimeter. Measured boundary-layer velocity profiles indicated that the flow parameter controlling the drag on a bluff body in drag-reducing flows is the turbulence intensity rather than the Reynolds number. For turbulence intensity less than 0.7% polymer addition induced delayed separation. For turbulence intensity over 1% the opposite effect was true. Time-averaged velocity profiles of water did not show any significant difference between self-induced and forced oscillatory flows. Heat, mass and momentum transfer of Newtonian and power-law non-Newtonian fluids were theoretically investigated using an implicit finite-difference scheme. The results clearly· indicated that shear-dependent non-Newtonian viscosity controls the entire transport processes of the power-law fluids. For the major portion of the boundary layer, it was found that the more shear thinning the material exhibits, the lower the skin friction and the higher the heat transfer result. Accounting for the motion of the stagnation point provided an improved prediction of heat transfer for Newtonian fluid.

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

doctoral

Department dc:contributor.department

Materials Engineering Science

Grantor

Virginia Polytechnic Institute and State University

Year dc:date.issued

1984

Author dc:creator

• Kim, Byung Kyu

Chairs dc:contributor.committeechair

• Telionis, Demetri P.
• Cramer, Mark S.

Committee members dc:contributor.committeemember

• Burton, Larry C.
• Diller, Thomas E.
• Baird, Donald G.
• Reifsnider, Kenneth L.
• McGrath, James E.

• Boundary layer
• Newtonian fluids
• Non-Newtonian fluids
• Fluid dynamic measurements
• Academic theses

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/10919/100792

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/100792