Determination of grain rate in the exit of acceleration pipes
It is offered a theoretical study of the work of corn planting device, acting on the principle of pneumatic pulsation. Compressibility of the air, other terms of gas dynamics and relation of pressure over the gap and in the gap are taken into consideration in calculation. In determining the relation of air pressure in the gaps to air pressure over the gaps and over the seed they have been used the equation of gas state, and a graph of the reduced air flow from the reduced rate. In describing the seed driving force changes there has been used study on internal ballistics by D. Corner and other prominent scientists. To determine seed rate in the exit of acceleration pipes it has been formed a differential equation of seed motion which takes into account: the mass of the seed, seed acceleration, the pressure under the seed (actual), the pressure in the chamber of undercoulter space, seed gravity, resistance of seed friction on wall tube, coefficient reflecting the ratio of seed midship section to the tube cross-sectional area. This formula expresses the dependence of the seed rate in the exit of the accelerating tube on the structural and technological parameters of the working body, the geometric dimensions of the seed and allows operating the structural parameters of the working body for the required output speed. Studies have confirmed the results of the expression, in cases where the coefficient, which is correlated with constructive requirements. The theoretical study can serve as a basis for the creation of the current sample of air seeder working on the principle of pneumatic pulsation.