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https://hdl.handle.net/11681/42761| Title: | The mechanics of snow friction as revealed by micro-scale interface observations |
| Authors: | Lever, J. H. Taylor, Susan Song, Arnold J. Courville, Zoe R. Lieblappen, Ross M. Weale, Jason C. |
| Keywords: | Abrasion High-resolution thermography Inter-granular bond failure Self-lubrication Snow sliding friction Wear |
| Publisher: | Cold Regions Research and Engineering Laboratory (U.S.) Engineer Research and Development Center (U.S.) |
| Series/Report no.: | Miscellaneous Paper (Engineer Research and Development Center (U.S.)) ; no. ERDC/CRREL MP-21-35 |
| Is Version Of: | Lever, James H., Susan Taylor, Arnold J. Song, Zoe R. Courville, Ross Lieblappen, and Jason C. Weale. "The mechanics of snow friction as revealed by micro-scale interface observations." Journal of Glaciology 64, no. 243 (2018): 27-36. https://doi.org/10.1017/jog.2017.76 |
| Abstract: | The mechanics of snow friction are central to competitive skiing, safe winter driving and efficient polar sleds. For nearly 80 years, prevailing theory has postulated that self-lubrication accounts for low kinetic friction on snow: dry-contact sliding warms snow grains to the melting point, and further sliding produces meltwater layers that lubricate the interface. We sought to verify that self-lubrication occurs at the grain scale and to quantify the evolution of real contact area to aid modeling. We used high-resolution (15 μm) infrared thermography to observe the warming of stationary snow under a rotating polyethylene slider. Surprisingly, we did not observe melting at contacting snow grains despite low friction values. In some cases, slider shear failed inter-granular bonds and produced widespread snow movement with no persistent contacts to melt (μ < 0.03). When the snow grains did not move and persistent contacts evolved, the slider abraded rather than melted the grains at low resistance (μ < 0.05). Optical microscopy revealed that the abraded particles deposited in air pockets between grains and thereby carried heat away from the interface, a process not included in current models. Overall, our results challenge whether self-lubrication is indeed the dominant mechanism underlying low snow kinetic friction. |
| Description: | Miscellaneous Paper |
| Gov't Doc #: | ERDC/CRREL MP-21-35 |
| Rights: | Approved for Public Release; Distribution is Unlimited |
| URI: | https://hdl.handle.net/11681/42761 http://dx.doi.org/10.21079/11681/42761 |
| Appears in Collections: | Miscellaneous Paper |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| ERDC-CRREL MP-21-35 .pdf | 1.31 MB | Adobe PDF |  View/Open |