Advisor

Derek C. Tretheway

Date of Award

1-1-2011

Document Type

Thesis

Degree Name

Master of Science (M.S.) in Mechanical Engineering

Department

Mechanical and Materials Engineering

Physical Description

1 online resource (x, 102 p.) : ill. (some col.)

Subjects

MicroPIV, Wetting, µPIV, Particle image velocimetry, Microfluidics, Fluid dynamic measurements

DOI

10.15760/etd.118

Abstract

A moving contact line is the idealized line of intersection between two immiscible fluids as one displaces the other along a solid boundary. The displacement process has been the subject of a large amount of theoretical and experimental research; however, the fundamental processes that govern contact line motion are still unknown. The challenge from an experimental perspective is to make measurements with high enough resolution to validate competing theories. An experimental method has been developed to simultaneously measure interface motion, dynamic contact angles, and local fluid velocity fields using micron-resolution Particle Image Velocimetry (µPIV). Capillary numbers range from 1.7 x 10^(⁻⁴) to 6.2 x 10^(⁻⁴). Interface velocities were measured between 1.7 µm/s and 33 µm/s. Dynamic contact angles were manually measured between 1.1 µm and 120 µm from the contact line, and calculated from µPIV data to within several hundred nanometers from the contact line. Fluid velocities were measured over two orders of magnitude closer to the contact line than published values with an increase in resolution of over 3400%. The appearance of a recirculation zone similar to controversial prediction below previously published limits demonstrates the power and significance of the method.

Description

Portland State University. Dept. of Mechanical and Materials Engineering

Persistent Identifier

http://archives.pdx.edu/ds/psu/7101

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