Numerical simulation of jet-lifting under variable gravity field

Tryana Garza-Cruz, Masami Nakagawa, Kris Zacny

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

We conducted a series of numerical simulations to investigate the efficiency of a pneumatic method to convey lunar soil under earth (9.8 ms -2) and lunar (1.62 ms-2) gravity field. This numerical modeling was based on PFC2D with a fluid and particle coupling functions. During simulations, air jet at various pressures was injected into a 0.2 m diameter and 2m long tube that was filled with 8 mm diameter spherical particles. It was determined that the pressure of 5×103 Pa was enough to loft particles at lunar gravity but not at earth gravity. Thus the jet-lifting method under reduced gravity conditions will be more efficient and will require the utilization of less injected gas than when used under Earth gravity conditions. Increasing the pressure to 104 Pa was enough to loft particles at earth gravity. When the air injection pressure was decreased to 103 Pa, the lofting under both gravitational fields ceased. We postulate that one of the important parameters in the fluidization of a bed of particles is the friction acting between neighboring particles. If the injected fluid cannot overcome such frictional forces, the sample would not be fluidized. As the more detailed observation suggest, this may be the major reason why at lower air pressures only the particles subjected to lunar gravity can successfully be jet-lifted.

Original languageEnglish
Title of host publicationEarth and Space 2010
Subtitle of host publicationEngineering, Science, Construction, and Operations in Challenging Environments - Proceedings of the 12th International Conference
Pages1284-1294
Number of pages11
DOIs
Publication statusPublished - Nov 29 2010
Externally publishedYes
Event12th International Conference on Engineering, Science, Construction, and Operations in Challenging Environments - Earth and Space 2010 - Honolulu, HI, United States
Duration: Mar 14 2010Mar 17 2010

Publication series

NameProceedings of the 12th International Conference on Engineering, Science, Construction, and Operations in Challenging Environments - Earth and Space 2010

Other

Other12th International Conference on Engineering, Science, Construction, and Operations in Challenging Environments - Earth and Space 2010
CountryUnited States
CityHonolulu, HI
Period3/14/103/17/10

Fingerprint

Gravitation
Computer simulation
Earth (planet)
Air
Fluids
Fluidization
Pneumatics
Friction
Soils
Gases

All Science Journal Classification (ASJC) codes

  • Building and Construction
  • Environmental Engineering

Cite this

Garza-Cruz, T., Nakagawa, M., & Zacny, K. (2010). Numerical simulation of jet-lifting under variable gravity field. In Earth and Space 2010: Engineering, Science, Construction, and Operations in Challenging Environments - Proceedings of the 12th International Conference (pp. 1284-1294). (Proceedings of the 12th International Conference on Engineering, Science, Construction, and Operations in Challenging Environments - Earth and Space 2010). https://doi.org/10.1061/41096(366)116

Numerical simulation of jet-lifting under variable gravity field. / Garza-Cruz, Tryana; Nakagawa, Masami; Zacny, Kris.

Earth and Space 2010: Engineering, Science, Construction, and Operations in Challenging Environments - Proceedings of the 12th International Conference. 2010. p. 1284-1294 (Proceedings of the 12th International Conference on Engineering, Science, Construction, and Operations in Challenging Environments - Earth and Space 2010).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Garza-Cruz, T, Nakagawa, M & Zacny, K 2010, Numerical simulation of jet-lifting under variable gravity field. in Earth and Space 2010: Engineering, Science, Construction, and Operations in Challenging Environments - Proceedings of the 12th International Conference. Proceedings of the 12th International Conference on Engineering, Science, Construction, and Operations in Challenging Environments - Earth and Space 2010, pp. 1284-1294, 12th International Conference on Engineering, Science, Construction, and Operations in Challenging Environments - Earth and Space 2010, Honolulu, HI, United States, 3/14/10. https://doi.org/10.1061/41096(366)116
Garza-Cruz T, Nakagawa M, Zacny K. Numerical simulation of jet-lifting under variable gravity field. In Earth and Space 2010: Engineering, Science, Construction, and Operations in Challenging Environments - Proceedings of the 12th International Conference. 2010. p. 1284-1294. (Proceedings of the 12th International Conference on Engineering, Science, Construction, and Operations in Challenging Environments - Earth and Space 2010). https://doi.org/10.1061/41096(366)116
Garza-Cruz, Tryana ; Nakagawa, Masami ; Zacny, Kris. / Numerical simulation of jet-lifting under variable gravity field. Earth and Space 2010: Engineering, Science, Construction, and Operations in Challenging Environments - Proceedings of the 12th International Conference. 2010. pp. 1284-1294 (Proceedings of the 12th International Conference on Engineering, Science, Construction, and Operations in Challenging Environments - Earth and Space 2010).
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