1:45 PM - 3:15 PM
[O08-P97] Analysis of Water Flow on the Martian Surface with a Gravity Variable Apparatus: 2nd Report
Keywords:Gravity Variable Apparatus, Mars Gravity, Water penetration, Capillary phenomenon
This study was conducted as a collaboration of three high school science clubs.
In previous experiments, the release of the " gravity variable apparatus " ascending capsule was operated by hand. To ensure identical conditions for release, an apparatus was fabricated to hold and release the ascending capsule. A urethane sheet is attached to the side of the ascending capsule. The ascending capsule is sandwiched by a board with a urethane sheet attached. Vibration was absorbed by moderate friction of the urethane sheets. For about 0.6 seconds, it was able to generate a gravitational environment of 0.362 ± 0.014 G, which is comparable to the gravity of the Martian surface.
Using this "gravity variable apparatus", a water penetration experiment was conducted to investigate the behavior of water on the Martian surface. The experimental apparatus was constructed using a plastic container, a rubber stopper and a chain. Water penetration into sand under terrestrial gravity was compared with water penetration into sand under Martian gravity. The water penetration velocity was clearly different between Earth gravity and Mars gravity. The water penetration velocity became the terminal velocity within the experimental time. For sand with a grain size of 1.5 to 2.5 mm diameter, the water penetration velocity was about 64.9 mm/s in terrestrial gravity and about 56.1 mm/s in Martian gravity. The water penetration velocity was about 26.6 mm/s for terrestrial gravity and about 24.6 mm/s for Martian gravity for sand with a grain size of 0.71-0.99 mm diameter. The water penetration velocity at terrestrial gravity was larger in both cases. Based on these results, we are attempting to theoretically consider the effects of gravity and sand grain size on penetration velocity.
In previous experiments, the release of the " gravity variable apparatus " ascending capsule was operated by hand. To ensure identical conditions for release, an apparatus was fabricated to hold and release the ascending capsule. A urethane sheet is attached to the side of the ascending capsule. The ascending capsule is sandwiched by a board with a urethane sheet attached. Vibration was absorbed by moderate friction of the urethane sheets. For about 0.6 seconds, it was able to generate a gravitational environment of 0.362 ± 0.014 G, which is comparable to the gravity of the Martian surface.
Using this "gravity variable apparatus", a water penetration experiment was conducted to investigate the behavior of water on the Martian surface. The experimental apparatus was constructed using a plastic container, a rubber stopper and a chain. Water penetration into sand under terrestrial gravity was compared with water penetration into sand under Martian gravity. The water penetration velocity was clearly different between Earth gravity and Mars gravity. The water penetration velocity became the terminal velocity within the experimental time. For sand with a grain size of 1.5 to 2.5 mm diameter, the water penetration velocity was about 64.9 mm/s in terrestrial gravity and about 56.1 mm/s in Martian gravity. The water penetration velocity was about 26.6 mm/s for terrestrial gravity and about 24.6 mm/s for Martian gravity for sand with a grain size of 0.71-0.99 mm diameter. The water penetration velocity at terrestrial gravity was larger in both cases. Based on these results, we are attempting to theoretically consider the effects of gravity and sand grain size on penetration velocity.