Table 1 Snapshots of granular materials in microgravity. The hourglass image represents the final state of the flow when the granular media flows from the narrow area to the wide area (hopper angle is 60°) in 0.063 G. The mass of the granular media m summarised in Table 1 is determined by the following equation: m = V60 ρmin, where V60 represents 60 % of the total volume of the narrower space of the hopper (the side of the hopper angle being 60 degrees), and ρmin is the minimum bulk density of the granular media (Supplementary Table 1). The value of V60 (60 %) is conservatively determined to avoid the overflow of the granular media.
From: Granular flow experiment using artificial gravity generator at International Space Station
Granular material (Mass packed in the hourglass) | Microphotograph | Hourglass image |
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#01 Alumina beads (6.72 ± 0.01 g) |
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#02 Silica sand No. 5 (Tohoku sand) (4.66 ± 0.01 g) |
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#03 Toyoura sand (4.38 ± 0.01 g) |
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#04 Lunar regolith simulant (FJS-1, sieved) (4.76 ± 0.01 g) |
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Granular material (Mass packed in the hourglass) | Microphotograph | Hourglass image |
#05 Phobos regolith simulant (3.35 ± 0.01 g) |
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#06 Martian regolith simulant (JSC MARS-1A) (2.36 ± 0.01 g) |
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#07 Silica sand No. 8 (Tohoku sand) (3.71 ± 0.01 g) |
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#08 Lunar regolith simulant (FJS-1) (4.93 ± 0.01 g) |
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