Application Of Mathematical Methods For Condition Monitoring Of Oil And Gas Facilities.

The difference schemes of the method of variable directions for numerical realization of two-dimensional models in different frames account for environmental heterogeneity of matter distribution have been presented. The schemes allow to measure concentration of substances in real objects through building of functions, modeling various boundary conditions. A software complex for their implementation has been devised and the test findings as well as their analysis have been presented. To model processes which parameters depend on three spatial coordinates, we have suggested numerical schemes for implementing three-dimensional models that are absolutely stable and have the second order of accuracy at all spatial coordinates. Contaminated areas of anthropogenic origin, particularly surface and underground waters as well as soils have been analyzed. The mathematical models of diffusion processes, based on the use of two- and three-dimensional diffusion equations with a wide range of boundary and initial conditions, have been suggested. It is determined that exact solutions prohibit studying of the peculiarities of their behavior depending on the type of boundary conditions, therefore we suggest using numerical solutions. [ABSTRACT FROM AUTHOR]