From invasion percolation to flow in rock fracture networks

The main purpose of this work is to simulate two-phase flow in the form of immiscible displacement through anisotropic, three-dimensional (3D) discrete fracture networks (DFN). The considered DFNs are artificially generated, based on a general distribution function or are conditioned on measured data from deep geological investigations. We introduce several modifications to the invasion percolation (MIP) to incorporate fracture inclinations, intersection lines, as well as the hydraulic path length inside the fractures. Additionally a trapping algorithm is implemented that forbids any advance of the invading fluid into a region, where the defending fluid is completely encircled by the invader and has no escape route. We study invasion, saturation, and flow through artificial fracture networks, with varying anisotropy and size and finally compare our findings to well studied, conditioned fracture networks.Comment: 18 pages, 10 figure

Теоретические аспекты кинетики изнашивания поверхностей деталей машин и механизмов

The paper considers wear process of part surface in friction as a total result of simultaneous elementary processes of interaction, loosening and damage of surface layers. From the point of view of friction kinetics the processes leading to initiation and running of wear mechanisms are described. Analysis of tribological investigations makes it possible to reveal micro-processes in tribo-joints that cause creation and development of a certain wear mechanism. The paper also shows interrelation between interaction of friction surfaces, structural loss of strength, damageability and a wear surface mechanism.Рассматривается процесс изнашивания поверхностей деталей при трении как суммарный результат одновременного протекания элементарных актов взаимодействия, разрыхления и повреждаемости поверхностных слоев. С позиции кинетики трения описываются процессы, приводящие к возникновению и протеканию механизмов изнашивания. На основании анализа результатов трибологических исследований раскрываются микропроцессы в трибосоединениях, приводящие к формированию и развитию определенного механизма изнашивания, а также показана связь между взаимодействием поверхностей трения, структурным разупрочнением, повреждаемостью и механизмом изнашивания поверхностей