High-speed mode movement of solid particles in turbomachines with radial blades
The introduction substantiates the relevance of research. The purpose of the work is to create and approbate a methodology for calculating the speed mode for movement of coarse solid particles along the radial blades of turbomachines. In the methodological part an analysis of the forces acting on a solid particle when sliding along the radial blades of turbomachines is carried out. A differential equation for motion of solid particles has been compiled and options for its solution have been considered. Analytical dependencies have been obtained that make it possible to determine the values of the relative and total velocities, as well as the angle between the corresponding vectors for the velocities of the particle as a function of time when it moves along the radius of the blade. A calculated estimate of the change in these parameters for a wide range variation of the friction coefficient of a particle on the rotor blade is carried out. It is shown that the total sliding velocity of the particle as well as its radial and transport components intensively increasing in the initial time range, asymptotically approach the linear functions of the particle coordinate, practically independent of its initial position, but linearly dependent on the angular velocity of the rotor rotation and nonlinearly - on the coefficient of friction of the particle on the blade. In this case, the exit angle of the particle does not depend on the radius and rotor angular velocity, but depends on the friction coefficient of the particle against the rotor blade. With an increase in the friction coefficient the relative and total velocities of particle motion decrease which leads to a decrease in the kinetic energy accumulated by the particles. Conclusions are drawn from the results of the study. It is noted that the results obtained can be used by design engineers when designing turbomachines with radial blades, as well as in the educational process when training mechanical engineers and process engineers.