Browsing by Author "Pantelis, G"

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    Derivation of a macroscale formulation for a class of nonlinear partial differential equations.
    (Australian Nuclear Science and Technology Organisation, 1995-05) Pantelis, G
    A macroscale formulation is constructed from a system of partial differential equations which govern the microscale dependent variables. The construction is based upon the requirement that the solutions of the macroscale partial differential equations satisfy in some approximate sense the system of partial differential equations associated with the microscale. These results are restricted to the class of nonlinear partial differential equations which can be expressed as polynomials of the dependent variables and their partial derivatives up to second order. A linear approximation of transformations of second order contact manifolds is employed.
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    Model for the description of oxidation in sulfidic waste rock dumps.
    (Australian Nuclear Science and Technology Organisation, 2000-03) Pantelis, G; Ritchie, AIM; Stepanyants, YA; Bennett, JW
    Basic mathematical equations which describe the processes of sulfide oxidation and gas and water transport in waste rock dumps are presented and discussed. The governing equations account for gas and water flow vaporisation and condensation with latent heat effects heat transport and mass balance. Gas water and solid phases are assumed to be in local thermal equilibrium at all times. Air is approximated as an ideal three-component gas. Different semi-empirical relationships between physical values are used: Darcy's law for fluid flow ideal gas law the Van Genuchten formula for the relationship between degree of water saturation and pressure head Mualem's formula for the relative hydraulic conductivity as a function of pressure head etc. Some important global quantities such as the fraction of sulfide sulfur oxidised and the global oxidation rate are defined and considered as functions of time. The full set of equations is collected and presented in explicit form convenient for further numerical modelling. The glossary of some technical terms and the table of definitions of the main parameters as well as their units and characteristic values are displayed.
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    Modelling water and contaminant transport in the Rum Jungle Mine overburden heaps.
    (Australian Atomic Energy Commission, 1987-04) Pantelis, G
    An outline is given of a computer model for water and contaminant transport in and around overburden heaps with those at the Rum Jungle mine site as a specific example. The model assumes the heaps to lie on a sloping shallow aquifer with identical hydraulic properties. The simulation is carried out for a 40 year period. After the first 20 years a cover which is effectively impermeable to infiltrating rainwater and air is introduced on the heap. The restriction of oxygen supply to the heap terminates contaminant production which results from oxidation of pyrite. Leaching of contaminants from the heap in the following 20-year period is examined.