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Capillary-pressure driven adhesion of rigid-planar surfaces
1Department of Mechanical and Aerospace Engineering, North Carolina State University, Raleigh, NC 27695-7910, United States. tward@ncsu.edu
Journal of Colloid and Interface Science
|December 22, 2010
Summary
This study investigates fluid adhesion between parallel plates. Under specific conditions, a suspended load can be held indefinitely as the gap spacing decreases, indicating stable adhesion.
Area of Science:
- Fluid mechanics
- Surface science
- Adhesion science
Background:
- Understanding adhesion of viscous fluids between surfaces is crucial in various industrial applications.
- Previous studies have focused on different parameter regimes, leaving gaps in knowledge for small gap spacings and specific fluid properties.
Purpose of the Study:
- To determine the conditions for adhesion of a viscous-Newtonian fluid film between parallel plates.
- To develop a theoretical model and validate it experimentally for small gap spacings.
Main Methods:
- Theoretical analysis using an analytical solution in the limit of small Reynolds and zero capillary numbers.
- Experimental investigation with viscous fluids (viscosity ~1000 cSt) at small gap spacings (10-100 μm) and applied loads (2.7N or 4.9N).
Main Results:
- An analytical solution was derived for the change in gap height over time.
- The load was observed to be suspended for extended periods, approaching indefinite suspension as gap spacing reached a critical value.
- Experimental results showed good agreement with the theoretical predictions.
Conclusions:
- The study successfully identified conditions for fluid adhesion under the investigated parameters.
- The findings suggest that for gap spacings below a critical value, indefinite load suspension is possible, demonstrating stable adhesion.
- The theoretical model provides a reliable framework for predicting adhesion behavior in such systems.
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