Effects of Covering Layer of Sand Particles on Particle‐Bed Collision and Aeolian Sand Transport. Issue 9 (14th September 2022)

• Record Type: Journal Article
• Authors: Zhang, C.; Dun, H.; Meng, X.; Huang, N.
• Is Part Of: Journal of geophysical research. Volume 127:Issue 9(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-09-14
• Subjects: covering layer of sand particle -- collision -- PTV -- recovery coefficient -- simulation; Planets -- Periodicals; Geophysics -- Periodicals; 559.9
• DOI: 10.1029/2022JE007267
• Languages: English
• ISSNs: 2169-9097

Abstract

Abstract: The movement of sand particles on the desert is the primary mechanism resulting in the development of sandstorms. Scientists have found that the physicochemical environments of terrestrial planets can cause the surface of sand particles to form a peelable covering layer, which may shed gradually during the movement of sand particles and affect the collision process between sand particles and bed surface, and finally affect aeolian sand transport itself. However, only a few studies have investigated these microscopic physical processes and conducted quantitative analysis of the relationship between covering layer mass and its coefficient of restitution (COR) when a particle impact desert surface. In this study, we collected four types of natural sand particles from the Badain Jaran, Mu Us, and Taklimakan deserts and the shoreside of the Yellow River respectively. A hydrochloric acid solution was used to dissolve the surface‐covering layer of sand particles, and high‐speed photography was used to capture the process of particle‐bed collision. The motion characteristics of the sand particles under different covering layers were analyzed using statistical analysis, and the quantitative formula between the COR and the covering layer mass was provided. This calculation result was further incorporated into an aeolian sand transport model to evaluate the effect of the covering layer on sand flux. Considering the ubiquity of covering layer on sand particle, the methodology proposed in this study can be used to simulate sand drift on Earth, Mars, and other terrestrial planets more accurately. Plain Language Summary: Aeolian sand on Earth, Mars, and other terrestrial planets is an important process that affects substance transport, landform evolution, and climate change. The sand grains are generally considered to be composed of only a single substance, and the material property affects their collision behavior and computational accuracy when assessing the sand hazards such as sandstorms. However, recent researches show that the surfaces of sand particles on terrestrial planets have 1–10 μm thick covering layers made out of metal oxides, which are different from the internal material and could be break off due to continuous collision and consequently change the collision behavior of sand particles. In this study, we collected natural sand particles from four different study areas. Chemical reagent was used to dissolve the covering layer and high‐speed photography was used to capture the process of collision. The motion characteristics of the sand particles were analyzed and a formula was proposed to describe this complex process. We built an improved calculation method for aeolian sand transport and may be used to simulate aeolian sand on Earth, Mars, and other terrestrial planets more accurately. Key Points: The collision processes between natural sand particles in four study areas and bed surface were recorded The quantitative formula between the coefficient of restitution and the covering layer mass was provided The methodology proposed in this study can be used to simulate sand drift on Earth, Mars, and other terrestrial planets more accurately