RESEARCH OF THE EFFICIENCY OF THE GRAIN RECEPTION LINE OPERATION FROM AUTO TRANSPORT AT THE PROCUREMENT PRODUCTION GRAIN ELEVATOR

The results of the study of the characteristics of the technological line for grain reception from auto transport at the procurement production grain elevator of LLC ―Agricultural Enterprise ―Vesna 21‖ are presented. In the process of research, the quantitative and qualitative composition, volumes and duration of the harvesting periods of early and late crops, the quantitative and qualitative composition and characteristics of auto transport delivering grain to the enterprise were determined; the most intensive supply of early and late crops, as well as the actual coefficients of daily irregularity of their supply by auto transport.It is shown that the enterprise in 2017-2019 traditionally received such early crops as wheat of 2-6 classes and rapeseed of the highest and 1st class. Late crops were represented by corn (3rd class and non-class) and soybeans (non-standard and extruded). The volumes of harvesting of the corn and wheat (main crops)for the indicated years correlated, respectively (%) 49.2:41.2; 60.1: 24.9 and 66.1:17.1, which indicates a tendency for a significant increase in the supply of late crops, especially corn grain. The ratio between early and late crops for 2017–2019 was 45:55, 24:76 and 20:80, respectively (%).The monthly grain flow to the grain elevator was rather irregular. Most of the grain was received from July to December, when the periods of harvesting of early and late crops coincide, and especially in the autumn months, in September, October and November, up to 32.9 %, less – in the off-season from January to June, to 12.3 %. All the same, a lot of grain in percentage terms was received in November 2017 and October 2018 – 32.9 % each.An analysis of the quantitative and qualitative composition of cars that delivered grain to the procurement and production elevator in 2017-2019 showed that the carrying capacity of the vehicles ranged from 3 ... 51 tons. In 2017, 80.9% of all grain received by the enterprise was delivered by 2771 vehicles (cars) with a carrying capacity of 20 ... 40 tons, which amounted to 82.4 % of their annual quantity. In 2018, these indicators were as follows – 87.2 % of grain was delivered by 84.5% of vehicles of the same carrying capacity, and in 2019 – 93.4 % of grain was delivered by 93.0 % of the same vehicles. In the years studied, there was a tendency to an increase in the share of more heavy-duty vehicles (35...40 t). However, the number of vehicles with a carrying capacity of more than 40 tons, delivering significant volumes of grain, has significantly decreased, which is associated with the legislative limitation of the vehicles weight. The optimal carrying capacity in terms of the ratio of the mass of the delivered grain: the number of vehicles, taking into account legal restrictions, can be recommended 35...40 tons.The main characteristics of the reception of an early and late crops at the procurement and production elevator, respectively, for 2017-2018 were the following values: the duration of the arrival of early crops, days - 126, 119 and 97, late – 142, 145 and 240; harvesting period of early crops, days – 73, 88 and 68, late crops – 86, 78 and 57; the most intensive supply of early crops, t/day – 8378, 596 and 1428, late crops 1966, 1576 and 1909; actual coefficients of grain reception irregularity by auto transport of early crops – 6.3; 2.2 and 3.6, late – 2.5, 2.4 and 2.9, which exceeds the standard values of 1.6 and should be taken into account when improving the operation of the grain reception line.

Effect of Dynamic Bridging on Homogeneous Grain Movement in a Microwave Processing Zone

This article describes the influence of dynamic bridging in the unloading of a hopper at a processing plant on the grain flow homogeneity in a convective-microwave zone. In accordance with calculation methods for unloading hoppers, the parameters of the hopper unit and those of the outlet hole insuring that grain flows without static bridging formation is defined. It was found that moisture content fluctuations do not affect the process of grain transport. The equation for dynamic bridging rise depending on its position on the vertical axis of the unloading hopper has been deduced that enables the definition of the inhomogeneity of grain flow from its outlet hole. Calculations show that a certain inhomogeneity occurred between the right and the left parts of the unloading hopper in relation to its vertical axis in the course of grain discharging. This effect underlies the inhomogeneity of grain processing and reduction of its effectiveness in convective-microwave zones. An experimental model of unloading the hopper has been manufactured in order to perform investigational studies. The results of studies have completely confirmed the hypotheses. It has been found that dynamic bridge formation in unloading of the hopper results in the inhomogeneity of grain flow in convective-microwave zone.

Studying Grain Flow Immersion into Liquids of Various Densities Based on the Methods of Experiment Design

Introduction. In addition to grain, a grain heap of rye may contain poisonous ergot sclerotia. Modern grain cleaning machines do not isolate ergot sclerotia in one technological process because of the similarity of physical properties in linear dimensions. Isolation of ergot sclerotia from rye grain in one technological process is possible through the use of aqueous solutions of inorganic salts. The purpose of the study is to determine the optimum elevation of the loading hopper relative to the liquid surface. The data obtained contribute to increasing the quality of the technological process of the machine being developed. Materials and Methods. The paper considers the delivery of rye grain flow from the loading hopper outlet into the liquid by varying the specific grain load, liquid density and the delivery height. To set up the experiments, the experiment design methods have been used. The experimental data have been processed using the statistical package Statgraphics Plus 5.1. Results. The estimation of the effective elevation of the loading hopper outlet relative to the liquid surface when delivering grain flow has been carried out. There have been obtained regression models for the fraction of grains, which did not submerge and rose up to the liquid surface with air bubbles. Discussion and Conclusion. It has been found that the density of the aqueous salt solution has a significant effect on the percentage of grains, which did not submerge and rose up to the liquid surface with air bubbles. The smallest values of at different density of the liquid and specific grain load are achieved at a grain delivery height 56.0 ∙ 10–3 m.

Study on Periodic Pulsation Characteristics of Corn Grain in a Grain Cylinder during the Unloading Stage

The fluctuation effect of corn grain often occurs during the unloading stage. To accurately explore the periodic pulsation characteristics of corn grain during the unloading stage, a discrete model of corn grain was established, and the effectiveness of the discrete element method in simulating the corn grain unloading stage was verified by a 3D laser scanner and the “spherical particle filling method”. The grain cylinder was divided into six areas, and the periodic pulsation characteristics at different heights were explored through simulation tests. The results showed that the faster the average speed of corn grain changes in unit time, the more significant the periodic pulsation characteristics were as the height of grain unloading increased. The corn grain pulsateon in the grain cylinder exhibited gradual upward transmission and gradual amplification in the process of transmission. The average velocity decreased with increasing height. The direct cause of pulsation was the variation in the average stress between grain layers. Simulation analysis of grain unloading for different half cone angles of the grain cylinder was carried out. The change in corn grain average velocity over time in the area below 20 mm of the upper free surface was extracted. The results showed that the speed of the top corn grain increased with increasing the half cone angle, and the periodic pulsation phenomenon became more obvious with increasing the half cone angle at half cone angles of 30–65°. A half cone angle of 65–70° marked the critical state of corn grain flow changing from funnel flow to overall flow in the grain cylinder. This study provides a method for studying the periodic pulsation characteristics of different crops during the grain unloading stage and provides a technical reference for the safe design of grain unloading equipment.

Substantiation of the presence and parameters of seed guides in the openers, which increase the quality of sowing and yield

One of the promising methods for improving the uniformity of seed distribution in the soil is the control of the grain flow by guiding elements in the openers. This creates favorable conditions for the flight of seeds in the openers and when leaving them backwards, which equalizes the speed, in modulus, of seeds and the unit, improves the uniformity of their distribution in the soil. The presence and parameters of the guiding elements of the openers was theoretically substantiated, which gave the development of the process of controlling the grain flow in the openers and at the exit from them by using the guiding elements. Analytical expressions have been obtained to determine the characteristics of the movement of particles on various surfaces, which are recommended to be used for guides in the openers. Experimental studies have shown that openers with guides reduce the coefficient of variation along the row by 20 ... 45% and have it 88 ... 98%, and in depth - 24 ... 27%. On the basis of experiments, it is recommended that 3 ... 4 guides are recommended for front openers (arithmetic mean interval along the row 18.5 ... 23.5 mm, coefficient of variation 88 ... 98%). The advantage of the experimental opener in the distribution of seeds by depth is due to the use of guide elements in combination with an improved soil shedding process. This eliminated the technological drawback - the formation of a sub-opener inclined surface (arithmetic mean interval 42 ... 37 mm, coefficient of variation 24 ... 27%). For a double disc opener, an improved guide is recommended, the bottom edge of which protrudes 2 cm in front of the vertical diameter of the discs and is located at a distance of 9 cm from the reference plane. The arithmetic mean spacing along the row of this opener is 15 mm, the coefficient of variation is 106%.

Building an analytical model of the gravitational grain movement in an open screw channel with variable inclination angles

Existing technical means for loading silos with grain material do not fully meet the needs of production. The issue related to grain injury remains urgent, which predetermines the need to design a gravitational loader of another principle of operation with the appropriate theoretical justification for the movement of grain material in it. This paper has presented and substantiated the model of the gravitational movement of grain in the peripheral open screw channel with two variable angles of inclination. The model is based on the system of forces in the cylindrical coordinate system, acting on the volume of grain flow in the peripheral screw channel. The grain speed at the end of the braking section of the channel should be as low as possible but not less than the initial flow rate at the beginning of the acceleration section. The model takes into consideration this condition and ensures the optimal passage of grain along any part of the channel. The reported model makes it possible to obtain the speed of grain movement at any time, takes into consideration the height of the bunker hole and the dependence between the angles of inclination of the spirals of acceleration and brake sections. A mathematical dependence is given for these angles that ensures the passage of grain without its discharge and, at the same time, prevents injury to the grain mass due to a controlled decrease in the resulting speed. A separate dependence is provided to find the time at which the grain increases its speed on the acceleration section, reaching the maximum value. Based on the model, a peripheral open screw channel with two angles of inclination of spirals α and β has been proposed. For this channel, the relationships between its key parameters have been established, in particular, values have been substantiated for the recommended angles of 41°…45° for the acceleration section and 39°…35° for the brake section, respectively, as well as the hо/r ratio not less than 0.6...0.7.

AN APPROXIMATE METHOD FOR CALCULATING GRAIN FLOW IN A VERTICAL CYLINDRICAL VIBROSIEVE

A modified hydrodynamic model of a stable grain flow of an inhomogeneous mixture over the surface of a vertical cylindrical vibrating sieve is proposed under the assumption that the porosity of the mixture in the moving annular layer depends on the velocity of movement. A linear dependence of the porosity of the mixture on the velocity of movement are accepted, where higher speed corresponds to higher porosity.. The calculation of the velocity is reduced to solving an inhomogeneous differential equation of the Bessel type. Further, by "freezing" the variable coefficient of this equation, the problem has been simplified. This simplification is permissible due to the fact that the thickness of the moving layer of the mixture is much less than the radius of the vibrating sieve. As a result, the dependence of the velocity on the radial coordinate is expressed through the elementary functions. A compact formula for determining the maximum grain flow velocity is obtained. By integrating, in elementary functions, the formula for the average velocity in the layer is obtained. An approximate formula for the performance of the vibrating sieve by the mass of the exit fraction is derived. For this, it is proposed to calculate the corresponding integral approximately by the Simpson formula, so as not to calculate the values of special functions of large argument using the asymptotic formulas. It is shown that the named productivity significantly depends on the porosity of the grain mixture. In order to obtain information about the actual errors of the approximate formulas, we additionally carried out the numerical integration of the original non-simplified Bessel-type equation on a computer. A comparative analysis of the calculation results confirmed the small errors of the simplifications introduced into the equation of motion, as well as the adequacy of the theoretical results obtained. By passing to a simplified differential equation, approximate formulas were derived and tested for calculating the main characteristics of the grain flow along a vertical cylindrical vibrating sieve, taking into account the change in porosity in the grain mixture layer from the velocity of movement. The work summarizes the known theoretical results obtained using hydrodynamic models of the motion of grain mixtures fluidized by vibrations. The generalization carried out slightly complicated the theory, because the final calculation formulas are quite compact and convenient in practical implementation.