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Editorial: Tribology in Snow and Ice
Environments
Igor Velkavrh
1
*, Werner Nachbauer
2
and Thomas G. Mathia
3
1
V-Research GmbH, Dornbirn, Austria,
2
Department of Sport Science, University of Innsbruck, Innsbruck, Austria,
3
UMR5513
Laboratoire de Tribologie et Dynamique des Systèmes (LTDS), Écully, France
Keywords: friction mechanisms, cold environment, winter sports, ice, snow, tribology
Editorial on the Research Topic
Tribology in Snow and Ice Environments
Tribology in Snow and Ice Environments belongs to the most unknown parts of Tribology as the
science of friction and wear. There are several reasons for it: the environment is hostile, the cost of
on-site experimental investigations is very high and in a great number of cases results are confidential
due to the competitive nature of the target applications in fields such as professional sports,
automotive, aerospace, or naval industries as well as military. The dissemination of scientificfindings
is therefore limited. At the same time, snow and ice friction represent some of the most complex
tribological phenomena with ambiguities in the understanding of the basic friction mechanisms. This
is due to a myriad of influencing parameters, the unstable structure of snow and ice and the relatively
vaguely understood properties of the interface that enables their low friction properties. Scientists are
confronted with a multi-scale multi-disciplinary approach involving physics, mechanics,
meteorology, rheology, kinesiology, geology, nivology, glaciology, and mathematics of
transitional irreversible phenomena. In the last decade, new theoretical and experimental
findings have challenged the existing theories and postulated a need for complete reformulation
of the frameworks describing snow and ice friction. At present, novel hypotheses were put forward,
which are supported by advanced analytical models and experimental procedures, but they are
scattered throughout the literature.
This Research Topic on “Tribology in Snow and Ice Environments”collects the last developments
in the field, written by researchers who have contributed significantly to the characterization of the
properties of snow and ice concerning their friction mechanisms. The articles address various areas
of the respective field but can roughly be ordered into three main groups: 1) topography and the
calculation and measurement of the real contact area for ice and snow surfaces, 2) the use of
specialized test-rigs for measuring of friction and tribological effects in snow and ice environments
and 3) review of existing mechanisms.
Scherge et al. present the results of sliding tests with five typical grinding structures and
compare them to calculations of the real area of contact. The measured ski base profiles and the
measured grain size distribution of granular snow were employed within a bearing model for a
rough surface in contact with loose and freely moving snow grains treated as ice spheres. For the
analyzed structures, this model revealed a good correlation of the real area of contact between ski
and snow with run times in lab-condition sliding tests. The results indicate that the snow-
containing volume of the grinding structure is pivotal for tailoring the sliding behavior.
Lungevics et al. provide a review of the existing surface measurement methods related to ice
tribology and present a holistic approach towards surface topography measurements for ice
tribology applications. The entire sample surfaces are scanned, and the measured data is
analyzed on different magnitude levels. This approach was applied to steel samples with
different topographies which were tested on two different ice tribometers. A more
Edited and reviewed by:
Roman Pohrt,
Technical University of Berlin,
Germany
*Correspondence:
Igor Velkavrh
igor.velkavrh@v-research.at
Specialty section:
This article was submitted to
Tribology,
a section of the journal
Frontiers in Mechanical Engineering
Received: 29 November 2021
Accepted: 20 December 2021
Published: 31 January 2022
Citation:
Velkavrh I, Nachbauer W and
Mathia TG (2022) Editorial: Tribology in
Snow and Ice Environments.
Front. Mech. Eng 7:824874.
doi: 10.3389/fmech.2021.824874
Frontiers in Mechanical Engineering | www.frontiersin.org January 2022 | Volume 7 | Article 8248741
EDITORIAL
published: 31 January 2022
doi: 10.3389/fmech.2021.824874
straightforward correlation between the sample surface
topography and its ice friction response was enabled. Brown
provides explanations of how to apply recent advances in
surface metrology science to understanding friction with
snow and ice. Building on four decades of research using
multiscale methods, in his article, two new surface
metrology axioms and corollaries are proposed and
potential applications of multiscale characterizations and
analyses with good potential to provide new technological
insights are provided.
Lemmettylä et al. present a custom-made ski tester, that was
developed for measuring of friction of skis on real snow under
laboratory conditions. Their ski tester is capable of glide testing
cross-country and skate skis as well as kick simulation for the testing
of grip waxes. In the presented study, glide testing precision was
completed under three different conditions. The ski tester can
distinguish the frictional differences between cross-country and
skate skis under gliding and kick testing conditions. However,
certain limitations due to the variations caused by the track
preparation process need to be considered. Wolfsperger et al.
present a novel approach towards the calculation of the speed of
freestyle skiers or snowboarders during the in-run of a jump. Their
work combines kinematic athlete data and comprehensive snow
surface measurements to infer the coefficient of friction of freestyle
skis and snowboards across a wide range of snow conditions. The air
drag and lift of athletes were deployed from wind tunnel
measurements. To solve the equation of motion for the
coefficient of friction between ski/snowboard and snow, a
mechanical model of the athlete was established. In their work,
Hasler et al. aim to find indications or evidence for the presence of
frictional meltwater in a ski/snow contact. The friction between the
snow and a cross-country as well as a flat ski is measured on a large-
scale linear snow tribometer at realistic skiing speeds from 5 to 25 m/
s. An infrared camera is used to analyze the snow temperature
behind the skis. From the maximum snow surface temperature, the
temperature at the spots where ski and snow are contacted are
estimated. Heat flow considerations lead to the conclusion that more
energy is dissipated into ski and snow than measured with heat flow.
The most obvious mechanism for the additional energy dissipation is
through snow melting. A second explanation may be provided by
deformations of the snow bulk or ice grains; however, a detailed
analysis of the energy consumption paths is currently not possible.
In their work, Lever et al. aim to assess our knowledge of the
mechanics underlying ice and snow friction. In the article, a
summary of the mechanical behavior of ice and snow substrates,
behavior which perhaps has not received sufficient attention in
friction studies is first presented. Afterwards, the strengths and
weaknesses of five ice- and snow-friction hypotheses: pressure-
melting, self-lubrication, quasi-liquid layers, abrasion, and ice-
rich slurries are assessed. Their assumptions are discussed and
evidence to determine whether they are consistent with the
postulated mechanics reviewed. Lastly, the key issues that
warrant additional research to resolve the specific mechanics
and the transitions between them that control ice and snow
friction across regimes of practical interest are identified.
We hope you will enjoy this Research Topic and we wish you
plenty of reading pleasure on the latest findings in “Tribology in
Snow and Ice Environments”.
AUTHOR CONTRIBUTIONS
All authors contributed to the conception and design of the
editorial.
Conflict of Interest: IV is employed by the company V-Research GmbH.
The remaining authors declare that the research was conducted in the absence of
any commercial or financial relationships that could be construed as a potential
conflict of interest.
Publisher’s Note: All claims expressed in this article are solely those of the authors
and do not necessarily represent those of their affiliated organizations, or those of
the publisher, the editors and the reviewers. Any product that may be evaluated in
this article, or claim that may be made by its manufacturer, is not guaranteed or
endorsed by the publisher.
Copyright © 2022 Velkavrh, Nachbauer and Mathia. This is an open-access article
distributed under theterms of the CreativeCommons Attribution License (CCBY). The
use, distribution or reproduction in other forums is permitted, provided the original
author(s) and the copyright owner(s) are credited and that the original publication in
this journal is cited, in accordance with accepted academic practice. No use,
distribution or reproduction is permitted which does not comply with these terms.
Frontiers in Mechanical Engineering | www.frontiersin.org January 2022 | Volume 7 | Article 8248742
Velkavrh et al. Editorial: Tribology in Snow and Ice Environments