Polymer-induced turbulence modifications in an impinging jet

This effort explores the impact of dilute polymer solutions on the turbulence characteristics in a submersed liquid impinging-jet configuration. Turbulent impinging jets are commonly used in technological applications such as drying, scouring, cooling or heating due to an enhancement in transport characteristics in the impingement region under certain nozzle-to-wall configurations. Previous efforts have identified significant turbulence modifications in the presence of dilute concentrations of polymer (i.e., the Toms effect) in both bounded (suppression) and unbounded (either suppression or enhancement) flows. To this end, particle-image velocimetry measurements were made for an axisymmetric turbulent impinging jet with a nozzle-to-wall distance H/D=6.8 and Reynolds number Re_D=23000. Measurements were made for both plain water and dilute polymer solutions of polyethylene oxide at concentrations of 50 and 100 ppm. The mean and turbulence characteristics of these three flows are contrasted and it is observed that the 50 ppm case yields a slight enhancement of the turbulence while the 100 ppm case exhibits clear suppression of the turbulence.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Theoretical & Applied Mechans

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2010

Author dc:creator

• Mejia Alvarez, Ricardo

Contributors dc:contributor

• Christensen, Kenneth T.

• impinging jet
• polymers
• Particle-image velocimetry (PIV)

Statement dc:rights

• Copyright 2010 Ricardo Mejia Alvarez

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/16174

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/16174