Hybrid molecular dynamics simulation approach for hypervelocity gas–surface interactions with first-principles accuracy

• Published in: Physics of fluids (1994) Vol. 37; no. 8
• Main Authors: Li, Jiashuo, Yan, Zixiang, Fang, Ming, Kang, Wei
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 01.08.2025
• Subjects: Accuracy; Design optimization; First principles; Gas-surface interactions; Helium atoms; Hypervelocity; Interaction models; Molecular dynamics; Simulation; Thermal analysis
• ISSN: 1070-6631; 1089-7666
• DOI: 10.1063/5.0276489

We show that it is possible to perform a first-principles precision molecular dynamics (MD) investigation of hypervelocity gas–surface interaction (HGSI) with the help of deep potential (DP) type interaction model as a bridge. A DP type interaction model specifically designed for HGSI is trained based on dataset generated from high-precision first-principles MD (FPMD) simulations of HGSI processes at a relatively small spatial scale, and then is directly integrated into MD simulations of large spatial and temporal scales to simulate complete HGSI processes. Special care is taken in the FPMD simulations to correctly describe the van der Waals interaction, which is of particular importance to HGSI. As an illustrating example, the HGSI process of helium atoms and aluminum surface is investigated with incident velocity ranging from 5.0 to 15.0 km/s. Accommodation coefficients and reflected velocity distributions of He atoms are calculated and show significant differences with MD simulations using empirical interaction potentials, which highlights the necessity for high-accuracy interaction model in HGSI investigations. In addition, we find that it is necessary to include high-incident velocity collision data in the generation of DP type interaction potential to guarantee the accuracy of interaction model in the context of HGSI. Results of this work may help to provide more accurate theoretical benchmarks for the prediction of aerodynamic properties and thermal loads, which is essential for the design and optimization of hypervelocity vehicles.