Molecular Dynamics Simulations

	Molecular Dynamics Simulations for Atomic Oxygen Effects on Carbon Based Materials in Space Koji Uenishi Department of Aeronautics and Astronautics, The University of Tokyo, Tokyo, Japan

Summary

One of the important problems for the spacecraft in the Low Earth Orbit is degradations of materials caused by atomic oxygen. In this study, the effects of atomic oxygen on carbon-based materials which will be used for long duration structures are simulated numerically using molecular dynamics method. The graphite structure is chosen as the target material in the analysis. The interactions between each of the carbon atoms, atomic oxygen, carbon monoxide and carbon dioxide which are produced by chemical reactions, are approximated by a two-body potential (the Lennard-Jones potential) function. The energy changes in chemical reactions (oxidation) are regarded as the changes of the potential energy functions. The numerical analysis is shown for the arrival of single atomic oxygen with high energy, its reaction with a carbon in the graphite and the atomic rearrangement in the graphite. The results giving some examples in a specified condition, this method can generally show the effects of kinetic energy of atom, reaction processes, target materials, surface temperatures etc., suggesting a new approach to the study of material degradations in space.

Keywords

Degradations of materials, Effects of atomic oxygen, Simulation, Space engineering.

Related Publication

Shioya, T., and K. Uenishi (1994). A Molecular Dynamics Simulation for Atomic Oxygen Effects on Carbon Based Materials in Space. J. Japan Soc. Aeronautical & Space Sci., 42(486), 436-443 (in Japanese).

Go back to the "Research Topics" Page.