Abrasion of flat rotating shapes
A E Roth1, C M Marques, D J Durian
1Department of Physics & Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6396, USA.
Summary
Flat linoleum "pebbles" erode into circles when rotated in abrasive grit. A new imaging method quantifies shape evolution, confirming a model of radial inward movement.
Area of Science:
- Materials Science
- Tribology
- Fluid Dynamics
Background:
- Understanding material erosion is crucial for predicting component lifespan.
- Quantifying shape changes during abrasive processes requires precise measurement techniques.
Purpose of the Study:
- To develop and validate a general method for quantifying the shape evolution of eroding objects.
- To investigate the dynamics of flat linoleum erosion in an abrasive slurry.
- To compare experimental results with a theoretical model of erosion.
Main Methods:
- Utilized digital photography from multiple angles to capture pebble contours.
- Developed a method to compute local curvature with controllable uncertainty.
- Employed shape descriptors to track changes over time.
- Compared experimental data to a proposed radial inward movement model.
Main Results:
- Observed consistent erosion of various initial shapes towards a circular form.
- Demonstrated that abrasion effectively halts once a circular shape is achieved.
- Achieved good quantitative agreement between experimental data and the proposed erosion model.
Conclusions:
- The developed imaging and analysis method accurately quantifies erosion-induced shape changes.
- The study confirms that abrasive erosion drives objects towards a stable circular shape.
- The proposed model provides a reliable prediction for the rate and pattern of erosion.
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