A study of influence of gravity on bulk behaviour of particulate solid

Yun Chi Chung, Jin Yeam Ooi

Research output: Contribution to journalArticlepeer-review

72 Scopus citations

Abstract

This paper examines the influence of gravity on the bulk responses of a granular solid. The loading scenarios in this study include confined compression, rod penetration into a granular medium and discharging through an orifice. Similar loading and flow conditions are likely to be encountered in the stress and deformation regimes that regoliths are subjected to in extraterrestrial exploration activities including in situ resource utilisation processes. Both spherical and non-spherical particles were studied using the discrete element method (DEM). Whilst DEM is increasingly used to model granular solids, careful validations of the simulation outcomes are rather rare. Thus in addition to exploring the effect of gravity, this paper also compares DEM simulations with experiments under terrestrial condition to verify whether DEM can produce satisfactory predictions. The terrestrial experiments were conducted with great care and simulated closely using DEM. The key mechanical and geometrical properties for the particles were measured in laboratory tests for use in the DEM simulations. A series of DEM computations were then performed under reduced gravity to simulate these experiments under extraterrestrial environment. It was found that gravity has no noticeable effect on the force transmission in the confined compression case; the loading gradient in the rod penetration is linearly proportional to the gravity; the mass flow rate in silo discharge is proportional to square root of the gravity and the angle of repose increases with reducing gravity. These findings are in agreement with expectation and existing scientific evidence.

Original languageEnglish
Pages (from-to)467-474
Number of pages8
JournalParticuology
Volume6
Issue number6
DOIs
StatePublished - Dec 2008

Keywords

  • Confined compression
  • Discrete element method
  • Extraterrestrial
  • Gravity effect
  • Particulate assembly
  • Rod penetration
  • Silo discharge

Fingerprint

Dive into the research topics of 'A study of influence of gravity on bulk behaviour of particulate solid'. Together they form a unique fingerprint.

Cite this