Studying the parameters of acceleration of irregularly shaped solid particles by laminar gas flow in the acceleration channel of the slit section

The article provides the relationship between the operating parameters of gasdynamic separation of granular mixtures by laminar gas flow (density, viscosity, absolute static pressure, temperature, linear velocity of the working gas, length, width, height of the acceleration channel, density, diameter, sphericity coefficient and effective coefficient of particles friction of each of the separated components against the wall of the acceleration channel) on the separation efficiency indicators (average particle velocities of the separated components and their ratio, the standard deviation of the particle velocity of each of the separated components). It is shown that the lower the particle velocity of each of the separated components, the higher the efficiency of gas dynamic separation. At the same time, in the case when, after exiting the acceleration channel, the particles are captured quickly enough and before that move along ballistic trajectories through a rarefied medium, the higher the separation efficiency, the higher the ratio of the average velocity of light particles to the average velocity of heavy ones. On the contrary, in the case where long-term movement of particles along a ballistic trajectory through a dense medium is assumed, the separation efficiency increases with a decrease in the velocity of light particles and an increase in the velocity of heavy particles. Due to the fact that it is impossible to give heavy particles a velocity exceeding the velocity of light particles in the acceleration channel, it must be stated that in this case the separation efficiency increases with a decrease in the ratio of the average velocity of light particles to the average velocity of heavy ones. An analysis is given of which relationships of these values are direct and which are inverse. General recommendations on setting the operating parameters for various special cases of gas dynamic separation are given.