Numerical investigations of the particle deposition in the human terminal alveoli under the Martian gravity

With the expectation of human landing on Mars in the near future, it is critical to understand how the Martian particles deposit in the human terminal alveoli to prevent the astronauts from health damage by the Martian toxic particles. Therefore, this study has numerically investigated the micro-particle behaviours in an alveolar model under Martian gravity using an Euler-Lagrangian method considering several physical and physiological factors. The important findings are as following: 1) Martian particle deposition is sensitive to the alveolar direction and respiratory depth significantly, but not sensitive to the wall motion pattern; 2) both the particle size and density affect the deposition starting time and duration; 3) compared with the earth gravity, the total deposition efficiency decreases and the total deposition time is much extended under the Martian gravity. It concludes that the particle deposition under Martian gravity environment are obviously different from the one under the earth gravity environment.