| Popis: |
An approach to modelling random phenomena, which are typical for actual particle phase in two-phase gas-particle flows, is developed. The collision of non-spherical particles with the wall, scattering of rebounded particles, collisions between particles, and the particle size dispersion are considered. Two kinds of the particle shape are taken in calculations: parallelepiped, and parallelepiped with cut vertices. The three-dimensional particle-wall collision problem is solved numerically using a non-sliding collision model. Scattering indicatrices for non-spherical particles rebounded from a smooth wall surface are studied systematically by direct numerical simulation of rebounding the great number of particles. A kinetic model is used for modelling a \"collisional gas\" of particles in the carrier gas flow. Particle size distribution is described by the lognormal law. The developed approach is incorporated into the gas-particle flow model, and detailed investigation of the particle phase flow structure is carried out for high-speed gas-particle flow over a blunt body (cylinder). The hierarchy of significance of the considered effects depending on the particles\' and flow parameters is constructed. The distribution of the particle energy loss in particle-wall collisions along the body contour is found for particles of different shape. The shielding effect of the particle-particle collisions on the energy loss is discussed. |
