Background: One of the labor-consuming and dangerous operations in technological process
of processing reactors is the one on transportation of firm wastes, as it is necessary to take into account
the danger of materials to an environment and their harmful influence on health of the attendants and
Objective: The recent paper is devoted to theoretical and experimental study of two phase (particle/air)
media propagation inside a pipeline (part of pulsed pneumatic transport devices where materials are
delivered to containers) with attention on possible harm influence of the flow on the tube walls, especially
at the pipelines bends.
Methods: Physical model corresponds to experimental study described in the patents. Numerical modeling
was performed within the framework of model of non-stationary two-dimensional motion of ideal
compressible media on the basis of laws of conservation of mass, momentum and energy. The thermodynamic
flow field has been computed both in gas and solid phases.
Results: Processes of particles mutual interactions, coalescence, fragmentation, interaction with a tube
surface and motion have been investigated in detail. Interface borders have been considered as contact
discontinuity surfaces. Modeling was performed numerically on the basis of the method of individual
particles. The comparison of the computational and experimental data stated in patents was executed as
Conclusion: It was found that the greater the radius of the pipeline bend R, the smaller value of gas
pressure we have in the bend, but this effect becomes insignificant for R > 2.2m. The values of gas
velocity at the bend have little variations depending on R. For small values of R (close to right angle of
the bend) inverse motion of the particles is possible that may result in blocking of the flow. The formation
of jet (consisting of particles) may take place at changing of radius R value (up to R = 1m). This
may lead to sufficient damage to pipeline walls. At R > 4m volumetric concentration of particles starts
to grow at the outer wall of the bend and effect of fragments dragging takes place that is also harmful
for device operation. So if the value of radius R belongs to the interval (1.5; 3.5)m, we have minimal
damage for the system operation.