Numerical simulation of two-phase “Air-Seed” flow in the distribution system of the grain seeder

This study is aimed at substantiating parameters of the two-phase “air-seeds” flow for the numerical implementation of a amathematical model describing the technological process of the grain seeder distribution system. The technique which was proposed can be further used to study and improve design and technological parameters of various pneumatic grain seeders. The “air-seed” flow regime is two-phase set by the Reynolds number and the bulk concentration of particles. To calculate these parameters, there is given an aerodynamic calculation of the air flow velocity to ensure the pneumatic distribution of seeds in the distribution system of the seeder. As the result, there were found: the air flow velocity for seed delivery and homogenous distribution on coulters for the entire pneumatic system; it was 8.71…9.1 m/s at the seed tube outlet (dispersion σ = 0,019, variation coefficient ν = 1,58%); mass concentration of seeds M = 0,92…7,1; volume concentration of seeds V = 8,4·10−4…6,5·10−3; Reynolds number of seeds 1250…4200; dynamic inertia of seeds τp = 0,63…4,72. The obtained parameters are necessary for numerical implementation of mathematical models for the technological process of the seeder pneumatic distribution system by two-phase flow mechanics.