Įelektrintų dalelių sluoksnio susidarymo ant filtravimo audeklo paviršiaus skaitinis modeliavimas

Abstract

Using software TOSCA,a numerical model of formation of a different size particle layer on the filtration material is developed, which evaluates the effect of particle electrification.The motion of particles is calculated by the most accurate method-the discrete elements method-which calculated directly the motion of each particle, i.e. evaluates its position, speed and forces acting at different periods of time.In modelling formation of an electrified particle layer, the part of the program, evaluating the influence of particle interrelationship was supplemented by the interrelationship of particle electromotive forces estimated in accordance with the Coulomb"s Law. On the basis of modeling graphics and numerical results, it is determined that during filtration of particles with preliminary electrification a layer is formed with the porosity by 25% higher than that of an unelectrified particle layer.The modelling results confirm the statement that, when using preliminary electrification of particles, a more porous layer is formed which predetermines a slower further growth of aerodynamic resistance. On the basis of the modeling results, it is possible to explain better "passing" of small particles through a filter using the preliminary electrification that was determined during experimental investigation. Due to a more porous layer and the electric field power between equally charged particles, the particle retention is reduced owing to diffusive filtration mechanisms.