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Effect of Melt Convection at Various Gravity Levels and Orientations on the Forces Acting on a Large Spherical Particle in the Vicinity of a Solidification InterfaceNumerical modeling was Undertaken to analyze the influence of both radial and axial thermal gradients on convection patterns and velocities claiming solidification of pure Al and an Al-4 wt% Cu alloy. The objective of the numerical task was to predict the influence of convective velocity on an insoluble particle near a solid/liquid (s/l) interface. These predictions were then be used to define the minimum gravity level (q) required to investigate the fundamental physics of interactions between a particle and a s/l interface. This is an ongoing NASA founded flight experiment entitled "particle engulfment and pushing by solidifying interfaces (PEP)". Steady-state calculations were performed for different gravity levels and orientations with respect to the gravity vector The furnace configuration used in this analysis is the quench module insert (QMI-1) proposed for the Material Science Research Facility (MSRF) on board the International Space Station (ISS). The general model of binary alloy solidification was based on the finite element code FIDAP. At a low g level of 10(exp -4) g(sub o) (g(sub o) = 9.8 m/square s) maximum melt convection was obtained for an orientation of 90 deg. Calculations showed that even for this worst case orientation the dominant forces acting on the particle are the fundamental drag and interfacial forces.
Document ID
20000073220
Acquisition Source
Marshall Space Flight Center
Document Type
Reprint (Version printed in journal)
Authors
Bune, Andris V.
(Universities Space Research Association Huntsville, AL United States)
Sen, Subhayu
(Universities Space Research Association Huntsville, AL United States)
Mukherjee, Sundeep
(Alabama Univ. Tuscaloosa, AL United States)
Catalina, Adrian
(Universities Space Research Association Huntsville, AL United States)
Stefanescu, Doru M.
(Alabama Univ. Tuscaloosa, AL United States)
Date Acquired
August 19, 2013
Publication Date
January 1, 2000
Publication Information
Publication: Journal of Crystal Growth
Publisher: Elsevier Science B.V.
Volume: 211
ISSN: 0022-0248
Subject Category
Solid-State Physics
Funding Number(s)
CONTRACT_GRANT: NCC8-66
Distribution Limits
Public
Copyright
Other

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