Discrete element modeling of planetary ice analogs: mechanical behavior upon sintering

• Published in: Granular matter 2022-02, Vol.24 (1), Article 12
• Main Authors: Dhaouadi, W., Marteau, E., Kolvenbach, H., Choukroun, M., Molaro, J. L., Hodyss, R., Schulson, E. M.
• Format: Article
• Language: English
• Subjects: Analogs; Bonding strength; Coefficient of friction; Complex Fluids and Microfluidics; Discrete element method; Enceladus; Engineering Fluid Dynamics; Engineering Thermodynamics; Flux density; Foundations; Geoengineering; Heat and Mass Transfer; Hydraulics; Industrial Chemistry/Chemical Engineering; Locomotion; Materials Science; Mathematical models; Mechanical properties; Original Paper; Parameter sensitivity; Physics; Physics and Astronomy; Planetary evolution; Probabilistic methods; Robustness (mathematics); Sensitivity analysis; Sintering; Sintering (powder metallurgy); Soft and Granular Matter; Solar system
• ISSN: 1434-5021; 1434-7636
• DOI: 10.1007/s10035-021-01167-6

Potentially habitable icy Ocean Worlds, such as Enceladus and Europa, are scientifically compelling worlds in the solar system and high-priority exploration targets. Future robotic exploration of Enceladus and Europa by in-situ missions would require a detailed understanding of the surface material and of the complex lander-surface interactions during locomotion or sampling. To date, numerical modeling approaches that provide insights into the icy terrain’s mechanical behavior have been lacking. In this work, we present a Discrete Element Model of porous planetary ice analogs that explicitly describes the microstructure and its evolution upon sintering. The model dimension is tuned following a Pareto-optimality analysis, the model parameters’ influence on the sample strength is investigated using a sensitivity analysis, and the model parameters are calibrated to experiments using a probabilistic method. The results indicate that the friction coefficient and the cohesion energy density at the particle-scale govern the macroscopic properties of the porous ice. Our model reveals a good correspondence between the macroscopic and bond strength evolutions, suggesting that the strengthening of porous ice results from the development of a large-scale network due to inter-particle bonding. This work sheds light on the multi-scale nature of the mechanics of planetary ice analogs and points to the importance of understanding surface strength evolution upon sintering to design robust robotic systems. Graphic abstract