A systematic approach is proposed to the theme of safety,reliability and global quality of complex networks(material and immaterial)by means of special mathematical tools that allow an adequate geometric characterizat...A systematic approach is proposed to the theme of safety,reliability and global quality of complex networks(material and immaterial)by means of special mathematical tools that allow an adequate geometric characterization and study of the operation,even in the presence of multiple obstacles along the path.To that end,applying the theory of graphs to the problem under study and using a special mathematical model based on stochastic geometry,in this article we consider some regular lattices in which it is possible to schematize the elements of the network,with the fundamental cell with six,eight or 2(n+2)obstacles,calculating the probability of Laplace.In this way it is possible to measure the“degree of impedance”exerted by the anomalies along the network by the obstacles examined.The method can be extended to other regular and/or irregular geometric figures,whose union together constitutes the examined network,allowing to optimize the functioning of the complex system considered.展开更多
A fibrous filter is one of the most common systems used to separate suspended particles from air. Two important factors (i,e,, the pressure drop and capture efficiency) are usually used to evaluate the performance o...A fibrous filter is one of the most common systems used to separate suspended particles from air. Two important factors (i,e,, the pressure drop and capture efficiency) are usually used to evaluate the performance of this type of filter, This study considers three two-dimensional arrangements of fibers (parallel, staggered, and random) to geometrically model fibrous media, The lattice Boltzmann method is employed to numerically simulate fluid flow through the filter, The Lagrangian form of the equation of motion of a particle is numerically solved to track the path of each particle in the flow field, where a one-way interaction between the fluid and particles is considered. The effects of pertinent parameters such as the fiber arrangement, solid volume fraction, particle-to-fiber diameter ratio, particle-to-fluid density ratio, Reynolds number, Stokes number, and size of the fibrous medium on the pressure drop and capture efficiency are studied. The obtained results are compared with existing empirical and theoretical findings and discussed.展开更多
文摘A systematic approach is proposed to the theme of safety,reliability and global quality of complex networks(material and immaterial)by means of special mathematical tools that allow an adequate geometric characterization and study of the operation,even in the presence of multiple obstacles along the path.To that end,applying the theory of graphs to the problem under study and using a special mathematical model based on stochastic geometry,in this article we consider some regular lattices in which it is possible to schematize the elements of the network,with the fundamental cell with six,eight or 2(n+2)obstacles,calculating the probability of Laplace.In this way it is possible to measure the“degree of impedance”exerted by the anomalies along the network by the obstacles examined.The method can be extended to other regular and/or irregular geometric figures,whose union together constitutes the examined network,allowing to optimize the functioning of the complex system considered.
文摘A fibrous filter is one of the most common systems used to separate suspended particles from air. Two important factors (i,e,, the pressure drop and capture efficiency) are usually used to evaluate the performance of this type of filter, This study considers three two-dimensional arrangements of fibers (parallel, staggered, and random) to geometrically model fibrous media, The lattice Boltzmann method is employed to numerically simulate fluid flow through the filter, The Lagrangian form of the equation of motion of a particle is numerically solved to track the path of each particle in the flow field, where a one-way interaction between the fluid and particles is considered. The effects of pertinent parameters such as the fiber arrangement, solid volume fraction, particle-to-fiber diameter ratio, particle-to-fluid density ratio, Reynolds number, Stokes number, and size of the fibrous medium on the pressure drop and capture efficiency are studied. The obtained results are compared with existing empirical and theoretical findings and discussed.