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Gravity Flow of Powder in a Lunar Environment (In Two Parts). 2. Analysis of Flow Initiation.
NTIS: PB 205 504 :20 pages
A small displacement-small strain finite element technique utilizing the constant strain triangle and incremental constitutive equations for elastic-plastic media, which are nonhardening and obey a coulomb yield condition, has been applied to the analysis of gravity flow initiation in a v-shaped hopper containing a powder under lunar environmental conditions. Three methods of loading were examined. Of the three, the method of computing the initial state of stress in a filled hopper prior to drawdown by adding material to the hopper layer-by-layer is superior. Results of the analysis of a typical hopper problem show that the initial state of stress, the elastic moduli, and the strength parameters have an important influence on material response subsequent to the opening of the hopper outlet.
IH; Report of Investigation;
NTIS Accession No.
NTIS: PB 205 504
Page last reviewed: March 11, 2019
Content source: National Institute for Occupational Safety and Health Education and Information Division