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Information × Registration Number 0201U003169, 0198U004838 , R & D reports Title Modeling of processes of transposition of the contamination in an ecological system water-air-soil popup.stage_title Head Savula Yarema Grygorovych, Registration Date 06-02-2001 Organization Ivan Franko National University of Lviv popup.description2 The heterogeneous mathematical models of the problems of an advection - diffusion in mediums with thin heterogeneity as curvilinear stratum and axisymmetric of channels are constructed. A heterogeneous character of these models stipulated by different regularity of the equations in a main medium and inclusion, and also different physical nature of transference in a main medium (diffusion) and inclusion (advection - diffusion). Because of offered mathematical models the variational statements are constructed and the problem of their correctness as the formulated existence theorems and uniqueness of a weak solution is investigated. For problem solving of an advection - diffusion with large number the Peclet the variants of stabilization of the numerical schemes are offered which consist of use of approximations high is ordinal, introduction stabilization of the equations and determination of analytical expression for stabilization of a parameter. The approach because of uses one from variants of a diffe rence method of a correction of streams offered Boris and Book is developed. The technique of a solution of two-dimensional initial-boundary value problems for the parabolic equations is constructed. It is based on the using of the fundamental solutions depended of the space and the time coordinates, isoparametric (linear and quadratic) boundary elements and collocation method. The developed algorithms of a solution of all formulated problems, their programs realization on the languages C ++, Delphi is carried out. The number of the test problems is considered. The problem of numerical realization of a finite element method, boundary elements and finite differences is investigated and obtained numerical solutions are compared. Product Description popup.authors popup.nrat_date 2020-04-02 Close