Molecular dynamics simulation of the lubricant conformation changes and energy transfer of the confined thin lubricant film

The lubrication system plays an important role in the reliability of moving links for spacecrafts while lubrication failure has emerged as one of the challenges in developing advanced spacecrafts with long life and high reliability. However, the process and mechanism of lubrication in space are still unclear due to a complex environment. In this study, the lubrication behavior under various pressure loads was studied by analyzing the lubricant conformation changes and energy transfer through molecular dynamics simulations. Results indicated that a “one-step” or “two-step” adjustment in the polymer conformations occurred, and the film exhibited different motion modes and temperature fields under different pressure loads. This work studied polymer thin film lubricant via energy transfer and molecular motion at a molecular level and gave a fundamental understanding on the lubrication behavior and lubrication failure of polymer thin film in space, providing theoretical guidance in developing advanced space lubrication technology.