Movement Of Grains Research Articles

PROCESS ANALYSIS OF GRAIN HULLING PROCESS

Cereals are an important source of energy and contain almost all substances necessary for the normal functioning of the human body, animals and birds. The anatomical structure of the grain has an outer shell that can be removed from the surface without destroying the starch core in many technological processes. One of the ways to improve the quality of the final product is to actively treat the surface of the wheat grain to remove the husks during its preparation for grinding. For this, peeling machines of various designs, shelling machines and machines with friction rotary knives are used. The grain is processed under the influence of impact and friction pulses in the working area of the machine, with different abrasive properties of the grain surface, external frictional forces are applied to the grain from the sides of the beater, which arise when the layers are moved along the surface of the beater. Grain is used for the production of starch, molasses and alcohol, and processed grain products include flour, pasta, cereals, bread and animal feed.Cereals are characterized by the fact that they are the main source of easily digestible carbohydrates, the main energy component of food. Bread made from wheat flour weighing 500 g, and which is made from flour of the highest grade, provides about 64% of the daily need for essential acids. The quality of the final product depends significantly on the grain preparation and processing processes. Peeling machines are used as one of the main machines for this. The transport movement of grain in the machine determines the time the grain stays in the working zone, which is achieved by placing different shaped bulls at an angle to the rotor axis, equipping the working zone with races, placing the roller at an angle to the horizontal plane and changing the rotation speed. The main disadvantages of such machines are the low efficiency of the peeling process and uneven surface treatment of individual grains in the cut state.

The study of grain transport effects on grain refinement under pulsed magnetic fields

The motion of grains within the molten metal under a pulsed magnetic field influences the influx of grains, thereby impacting the refinement of the solidification structure of metal. Physical simulation experiments, solidification studies, numerical simulations, and theoretical analyses are combined to investigate the motion patterns of grains in molten metal subjected to a pulsed magnetic field in the case of identical power. The findings suggest that grain movement occurs in two primary phases: initially, within the non-flow area at the solid-liquid interface, where grains respond to electromagnetic forces, and subsequently, within the flow area where the molten metal carries the grains. The speed of grain transport in the flow area directly influences the movement of grains in the non-flow area, then affecting the refinement of the metal solidification structure. The study introduces the concept of "transport characteristic time" to quantify the transport capacity of grains within the flow area, which enables a quantitative analysis of refinement effect under identical power conditions.

Operating features of a small capacity grain grinder with a hex rotor for agricultural farms

This article emphasizes the essential need for technical solutions in small-scale electromechanization tailored for private and small farms to efficiently manage labor-intensive tasks related to caring for farm animals and poultry. The focus is on utilizing single-phase electric motors of low power known for their simple and reliable design, available at a competitive market price. The paper introduces a design and technological diagram, structure, and operational principles of a versatile rotary grain crusher specifically engineered for grinding grain feed. The study gives a theoretical analysis of grain deformation processes within the grain crusher and the movement of grains within the working chamber. Through a concise theoretical examination of the machine’s working chamber, the research validates the potential of the proposed design and technological scheme for the grain feed grinder. This analysis underscores the machine’s promise in delivering the desired quality of the technological process while significantly reducing specific energy consumption compared to existing production models.

The study of the distribution of temperature fields of wheat grain along the vertical levels and horizontal layers during storage in the elevator silo

This article presents an analysis of the temperature fi elds caused by seasonal fluctuations in the temperature of the outside air on the surface of the walls of the silos and inside the outdoor silo located on the south side of the precast concrete elevator for the annual cycle from March 2018 to March 2019. The paper analyzes the data of grain temperature along the horizontal layers of the silo at the upper and lower levels and the distribution of temperature fields over the upper and lower levels of the silo during heating and cooling of the grain. A comparative analysis of the heating and cooling rates and the effect of temperature differences in the silo on moisture absorption processes in the grain mass during storage is carried out. During the statistical processing of the experimental data, the following trends were obtained: in the deep layers of the grain, when the grain is heated, the temperature is lower, and when the grain is cooled, the temperature is higher than in the nearwall layers. The rate of temperature change in the grain mass depends on the location of the grain at different levels and on the horizontal layer. The average cooling rates were lower than the grain heating rates, and during the annual cycle, heat accumulation in the grain mass stored in the silo is possible. The infl uence of thermal moisture conductivity on the change in the humidity regime in the silo is considered. The results for the annual cycle indicate a cyclical change in the relative humidity of the intergranular space and an increase in the relative humidity in the summer-autumn period (from May to November) above the optimal value recommended for long-term storage. To eliminate the risks of grain moisture, the need for periodic movement of grain from silo to silo during long-term storage is substantiated.

Separation of asbestos concentrates in a hydrocyclone

Relevance. Issues related to the operation of hydrocyclones in the asbestos industry for the separation of finely split asbestos fibers from rock impurities and non-fluffed asbestos needles used in the wet enrichment of brittle chrysotile asbestos, as well as some types of amphibole asbestos and in the purification of commercial grades of chrysotile asbestos of normal strength from magnetite are considered. Purpose. The purpose and objectives of the research is to study the operating modes of a hydrocyclone for the separation and desliming of asbestos products. Particular attention is paid to the behavior of particles inside the hydrocyclone. Methodology. The formulas presented in the literature for calculating the volumetric delivery of hydro-cyclones are analyzed. As a result, it was determined that the volumetric delivery of the hydrocyclone does not depend on the size of the sand nozzle and that the influence of the latter affects mainly the specific distribution of water between the discharge and sand products. Results. In the course of processing the obtained experimental data, the calculation results showed that, at different nozzles and feed heads, the movement of grains of separation mesh in the internal flow of hydrocyclones of the tested design occurs within 1 < Re < 20. Therefore, the accepted dependences of Ψ on Re when deriving the calculated formulas are correct. Conclusions. The volumetric delivery of hydrocyclones D = 75 mm and D = 200 mm of the tested design for feeding and draining depends on the feed head and the diameter of the framework nozzle. The established regularities in the behavior of particles of asbestos concentrates in hydrocyclones are of practical importance and can be used when choosing the technological parameters of their operation to achieve the specified conditions for the size of particle separation mesh.

ANALYSIS OF SPATIAL PRICE VARIATION IN MAIZE AND SORGHUM MARKETING IN KADUNA STATE, NIGERIA

The study analyzed spatial price variation in maize and sorghum marketing in Kaduna State. The data set for this analysis was monthly average secondary prices from 1999-2015. Data was analyzed using Augmented Dicker Fuller (ADF) test and Cointegration test and was performed using Stata 14.2 version of software. The results of the analysis showed that prices were found to be stationary at level and first difference and there is co-integration between the reference market and other markets. The equilibrium relationship between the price of maize and sorghum in Saminaka market and other markets was found to be positive. The speed of adjustment to the long run for sorghum between Saminaka-Giwa, Saminaka-Makarfi, and Saminaka-Godogodo was -1.08, -0.98 and -1.03 respectively, while that of maize was -1.98, -1.56, and -1.02. Implying that variation in prices are fully transmitted within a period of one month. It is recommended that government should ensure improvement of the operational environment of the marketers thereby drastically reducing transfer cost involved in the movement of grains across spatially separated markets.

Mathematical modeling of vibration drying process taking into account the longitudinal movement of grain material

Purpose. Construction of a mathematical model of non-stationary thermal mass transfer in the drying process in the vibration equipment, taking into account the longitudinal movement of the grain material. Methods. Mathematical modeling methods based on a formalized description in the form of two nonlinear inhomogeneous differential equations of the non-stationary process of drying grain material in a vibrating dryer taking into account longitudinal movement. Results. A mathematical description of the process of drying grain material in a vibrating grain dryer has been formed, taking into account the longitudinal movement of grain in the form of a diffusion mathematical model for determining the distribution of moisture content and material temperature along the length of the vibration transporting support surface. Two-step identification of model parameters based on experimental data is applied. Conclusions. A mathematical description of the nonstationary drying process of grain material in a vibrating dryer taking into account longitudinal displacement is formulated, in the form of two linear inhomogeneous differential equations that can be used to optimize the regime parameters of existing grain dryers. Keywords: drying, grain material, mathematical model, diffusion displacement, moisture content, temperature, speed.

Modeling the process of grain separation by density in a combined vibro-pneumatic and air-gravity unit

It was established that the method of intensifying the course of the work process is the organization of supplying the layer with a pulsating flow of air. Using a pulsating air flow, it is possible to change the magnitude of the aerodynamic effect on the grain mass by changing the magnitude of the force pulse under conditions of constant speed. At the same time, the effect of the pulsating flow on the ability to move grains of different mass (density) will be different, which can intensify the separation of seeds by density. The study of the combined effect of vibrations and pulsating air flow on the stratification of the grain flow and separation by density is an important scientific and technical task. The conducted analysis of publications revealed a promising possibility of using serial vibrating screen machines with a pneumatic system for the preparation of combined machines with a pneumatic system for the preparation of high-quality seeds, instead of vibro-pneumatic tables. To study the efficiency of the combined use of vibropneumoliquefied and pneumogravitational movement of the material. It is substantiated that the intensifying effect of the pulsating flow consists in the different force of influence on light and heavy grains. The mathematical description of the process of separation of loose material by density is based on the equations of motion of a particle in an oscillating medium, which is valid for any continuous medium that has the property of inertness. Formulated mathematical models of the processes of movement of components of grain material in the vibro-liquefied layer and in the air channel of the vibro-pneumocleaning machine will allow to determine the trajectories of the movement of grains in the working zones and, based on their analysis, to justify the parameters of the working bodies. The approbation of the mathematical description of the processes of separation of the components of grain material confirmed the increase in the efficiency of the use of pulsating flows for the separation of grain by density.

THEORETICAL STUDIES OF THE PROCESS OF GRAIN MATERIAL MOVEMENT ON THE SURFACE OF THE STEPPED VIBRATING FEEDER

A mathematical description of the movement of caryopses in the composition of the components of grain material (CGM) on the surface of a stepped vibrating feeder is given when CGM is introduced into the aspiration channel of the separator under the action of vibrations on the CGM. The trajectories of movement of grains on the surface of the vibrating feeder with different sizes were obtained. The obtained equation of the movement of seeds under the action of vibrations makes it possible to determine the dependence of the speed of movement of the material in the CGM layer on a number of factors: the geometric parameters of the vibrating feeder, the angle of material feeding, the initial kinematic mode of the grain material, the indicator of the kinematic mode of the vibrating feeder, and the friction coefficient of the CGM. The process of movement of grain material on the stepped surface of the vibrating feeder has been substantiated, which makes it possible to determine the rational parameters of introducing the CGM into the aspiration channel of the separator and uniform distribution in the channel with the subsequent possibility of its fractionation. The dependence of the function of the flow rate of grain material on the stepped surface of the vibrating feeder is obtained, which makes it possible to determine the parameters of the distribution of grain material over the sectional area of the aspiration channel of the separator. The estimation of the absolute speed of grain material movement on the stepped surface of the vibrating feeder is made on the basis of a mathematical model constructed by hydrodynamic analogy, which in turn predetermines the analysis of the recombination of caryopses along the thickness of the vibrated layer of grain material. According to the established mathematical models, graphical dependences of the absolute speed of movement on time, the trajectories of the array of particles, the calculated trajectories of particles of grain material, which are fed into the pneumatic channel under initial conditions, were built.

Research on nonlinear damage hardening creep model of soft surrounding rock under the stress of deep coal resources mining

To better understand the creep mechanical behavior of deep soft rock coal seam and more accurately predict the long-term deformation of the surrounding rock. Firstly, the electron microscope scanning test under different magnifications and a step loading creep test of deep soft rock were carried. the creep of the soft rock has the characteristics of ”sudden change”, and the propagation and combination of crystal particle cracks lead to the damage of rock mass, and the extrusion and dislocation movement of grains along the cavity hardens the rock mass. Deep rocks have both damage and hardening mechanisms in the creep deformation process, and there is a game relationship between them. Secondly, the damage variable and hardening function are introduced into Hooke’s body and Kelvin’s body, respectively, and connected in series with the adhesive dashpot with nonlinear viscosity coefficient containing power function, to establish the nonlinear damage and hardening creep model of three elements. Finally, the creep model agrees with the creep test data, which can accurately determine the opening time point of accelerated failure and the long-term strength of deep soft rock. This study provides a theoretical basis for creep laws of soft rock, which can effectively guarantee the long-term stability of deep energy extraction projects.

ДОКУМЕНТАЛЬНЕ ВІДОБРАЖЕННЯ ВИТРАТ І ВИХОДУ ПРОДУКЦІЇ ГАЛУЗІ САДІВНИЦТВА

The specifics of the industry imposes special requirements on the primary documents, and their diversity is not used, apparently, in any activity. The production of horticultural enterprises is characterized by a variety of conditions for receipt, storage and use of products. This article is devoted to the study of the documentation of costs and output of horticultural enterprises. Analyzing the issue of documenting the costs and output of horticulture, it should be noted that documentation is an important element of the method of accounting, because it serves as a basis for primary monitoring of business transactions and is a prerequisite for their reflection in accounting. In their activities, agricultural enterprises have the right to use both standard and specialized forms of primary documents approved by the relevant public authority. Documentation of business transactions can be carried out using self-made forms, which must contain mandatory details or details of standard or specialized forms. Primary documents are the foundation of accounting and tax accounting. Their absence or shortcomings in filling can be fatal for the financial condition of the enterprise. Therefore, the topic of compiling primary documents is always relevant. The primary documents on the accounting of costs and output of horticultural products are covered, as well as the limit-withdrawal card for material values at SE “DG Podilska DSS IS NAAS” and statement No 80 “Movement of grain and other products”. It is worth noting that the limit-withdrawal cards at this research station for the production of horticultural products in the accounting department in accordance with the plan of sowing seeds and fertilizers. The limit-taking cards indicate the sowing area (fertilizer application) and the seeding rate (fertilizer application) per unit area. In some cases, the withdrawal card may be opened for individual production orders for the production of horticultural products. An indicative plan has been drawn up – a schedule of documents for the receipt, disposal and internal movement of horticultural products according to the State Enterprise “Podilska DSS IS NAAS”.

Determination of characteristics of grain movement in the presence of dry friction forces and resistance of the environment

Purpose. Determination of the effect of air resistance on the parameters of particle movement on rough surfaces and determination of the particle movement resistance coefficient. Methods. Based on the analysis of modern ideas about the mechanisms of the formation of hydrodynamic (aerodynamic) resistance of the environment during the movement of a solid body, the form of recording the resistance force (formalization of the resistance force) is determined, and in accordance with the accepted form of representation of the resistance force, which depends on the aerodynamic regime (Reynolds number), the equation of motion is formulated along the surface in a stationary or moving air environment according to the value of the active forces. To identify the constant coefficients of differential equations, their analytical (symbolic) solution is obtained in the form of dependences of displacement S on time t. The coefficients included in the equation are determined from the experimental data (direct measurements of S and t) from the dependences of S(t). The movement of a single particle or several connected particles along a real surface (smooth, artificially rough, perforated, etc.) of a plane inclined to the horizon at an angle α was used as a model of physical and virtual experiments. The size of the angle α changes the speed of movement of the particle and the time it stays on the plane. Results. Theoretical and experimental studies of the movement of particles of grain material along sloping surfaces (feeding device) were carried out, which made it possible to determine the characteristics of the movement of the material: speed of movement, speed of descent of the grain from the support surface, coefficients of friction and aerodynamic resistance for different groups of grain material. Conclusions. The coefficients of friction and aerodynamic resistance of the air medium determined by the proposed method make it possible to use known theoretical mathematical models to calculate the parameters of particle movement on an inclined plane with maximum accuracy. Keywords: grain material, support-slope surface, speed of grain movement, coefficient of friction, aerodynamic resistance, equation of dynamic movement of grain.

Separating grain thrower for processing grain material

Research is underway to develop a grain separator. This device performs processing of grain material including cleaning, drying and cooling of grain. The device is able to perform all these operations. Currently, such machines do not exist. Known machines are able to perform only one process. The proposed device differs from all known machines in that it is able to perform the entire complex of works on the processing of grain material. The device consists of a rotating drum, where separating and other elements are installed, allowing to carry out the flight of the grain material into the air stream. The purpose of the research is to study the influence of the main parameters of the separating grain thrower on the processing efficiency of grain material. The geometrical parameters of the device are calculated using differential equations analytically describing the movement of grain in the drum of the device. Experimental setup was made for laboratory research and confirmation of theoretical studies. The tests confirmed the theoretical conclusions.

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.

MATHEMATICAL SIMULATION OF THE MOVEMENT OF GRAIN MATERIAL ON THE SURFACE OF THE SPREADER UNDER ITS INTRODUCTION INTO THE ASPIRATION CHANNEL OF THE SEPARATOR

Develop a mathematical model and calculated analytical dependences to determine the trajectories and parameters of grain movement on the surface of the vibrating feeder under the conditions of its introduction into the aspiration channel of the separator. They are based on the methods of mathematical modeling and theoretical mechanics with the application of the equations of motion of a material point under the variable action of vibrations. Theoretical research was conducted using mathematical analysis and modeling theory. The research results are processed using elements of probability theory and mathematical statistics using application packages. A mathematical description of the movement of grains of grain material components (GMC) on the surface of the vibrating feeder under the conditions of its introduction into the aspiration channel of the separator under the conditions of vibration on the GMC. The trajectories of grains on the surface of the vibrating feeder with different size are obtained. The obtained equation of motion of the particle under the action of vibrations allows to determine the dependence of the velocity of the material in the vibrated fluidized bed on a number of factors: geometrical parameters of the vibrating feeder, feed angle, initial kinematic mode of grain material, kinematic mode of the vibrating feeder and friction coefficient. The process of grain material movement on the flat surface of the vibrating feeder is described, which allows to determine the rational parameters of material introduction into the aspiration channel of the separator for its further fractionation. The dependence for the function of the grain flow rate on the flat surface of the vibrating feeder is obtained, which allows to determine the parameters of the grain material distribution by the cross-sectional area of the aspiration channel of the separator. The velocity of grain material on the flat surface of the vibrating feeder is estimated on the basis of a mathematical model constructed by hydrodynamic analogy, which in turn determines the analysis of grain recombination by the thickness of the vibrated liquid layer of grain material.

Comparative analysis of operation indicators of flat sieve vibrating in horizontal plane

Possible ways to develop the sieves of cleaning machines due to indicators improvements, increasing the quality of separation are presented. Sieve vibration modes in the horizontal plane applied to the sieve-cleaning machine are considered. Regularities of the grain separation process of the flat sieves vibrating in the horizontal plane are also presented. The dependences between grain material parameters and the uniform seed distribution over the sieve area with different directions of sieve vibrations are given. It is revealed that the complication of law results of sieves vibrations increases the probability of the sieve hole that particle are entering which allows one to increase the quality of grain heap separation, thereby significantly affecting the performance of the grain machine. Circular vibrations of punching sieves with the holes set at an angle to the direction of gathering to produce grain movement on the cycloid relative to the sieve surface and spin on its axis relative to the sieve hole. This movement of grain improves the quality of its separation from weeds.

Investigation of the process of pneumatic vibration separation of grain by density during one-dimensional movement of grain flow

Annotation Purpose. Formation of a mathematical description of the process of moving grains with different density in vibro-pneumatic liquefied grain medium under the action of pulsating air flow to determine the parameters of movement and the possibility of their separation into fractions. Methods. Theoretical determination of the dependences of the motion of grains with different densities in a vibro-pneumatic grain medium with pulsating air flow determines the mathematical method of research based on the addition and numerical solution of the equations of grain motion in a pneumatic vibrating separator. The mathematical model is formed as a result of drawing up the scheme of force interaction on grain in the vibro-pneumatic liquefied grain environment and the differential equations of movement of grains which are presented by a material point and indicators characterizing physical and mechanical properties of grain environment are received. Results. The motion of the center of mass of grains is considered as the motion of a certain particle, the coordinates of which coincide with the coordinates of the moving coordinate system (x, y), and the mass of a single grain m differs from the grains of the medium in density. The change of air flow velocity and the influence of pulsating air flow on the flow of grain material moving on a vibrating perforated surface are determined. The discrete-periodic change of the flow velocity, which is fed through the perforated support surface into the layer of grain material, is analytically described. The parameters of the grain motion process in an oscillating fluidized medium are determined, which are determined by the solution of a complex system of differential equations using computational methods using a PC. Conclusions. As a result of theoretical research, the possibility of increasing the efficiency of separation of grain materials by specific gravity of grains, by intensifying the process of separation of grain material provided the use of pulsating air flows to separate mixtures on vibrating surfaces and compared with existing separators using horizontal and inclined decks grain separation efficiency material increases by 35–42%. Keywords: pulsating air flow, grain, density, trajectory, fluidized medium, separation process, harmonic law of motion.

Laying the Corpses to Rest: Grain, Embargoes, andYersinia pestisin the Black Sea, 1346–48

When, how, and why did the Black Death reach Europe? Historians have relied on Gabriele de’ Mussi’s account of Tatars catapulting plague-infested bodies into the besieged city of Caffa on the Crimean Peninsula. Yet Mussi spent the 1340s in Piacenza; he had no direct knowledge of events in Caffa. Sources by people present in the Black Sea during the Second Pandemic, including Genoese colonial administrators, Venetian diplomats, Byzantine chroniclers, and Mamluk merchants, offer a different perspective. They show that the Venetian community at Tana played an important role in plague transmission; that it took over a year (from spring 1346 to autumn 1347) for plague to cross the Black Sea to Constantinople; that people crossed the Black Sea in 1346 but commodities did not because of a series of trade embargoes; that grain was one of the most important Black Sea commodities in both volume and strategic value; and therefore that the embargoes of 1346 delayed plague transmission by temporarily halting the movement of grain with its accompanying rats, fleas, and bacteria. When Venice, Genoa, and the Golden Horde made peace and lifted their embargoes in 1347, both the grain trade and the spread of plague resumed.

Macroscopic seismic responses of layered linear anelastic solids: Wave-induced internal deformations beyond the viscoelastic model

Seismic wave propagation within thinly layered anelastic reservoirs is modeled by direct application of Lagrangian continuum mechanics. Instead of postulating viscoelastic Q-factors or specific microscopic mechanisms, the anelastic properties of the layers are modeled by using generalized macroscopic internal variables. These variables represent averaged measures of various types of internal deformations of the rock, such as relative movements of grains, inclusions, pores and mobile dislocations, wave-induced pore-fluid flows (WIFFs), capillary and layer-boundary effects, or temperature variations. The continuum-mechanics model reveals the existence of body-force (Darcy-type) frictional effects, which are also absent in the viscoelastic model. To implement the attenuation effects observed in laboratory studies, the mechanical properties of the layers are represented by standard linear solid (Zener) rheologies approximating a mesoscopic-scale WIFF effect known as the drained/undrained transition. Optionally, the layer rheologies also include Biot’s poroelastic effects. All compressional- and shear-wave transmission, reflection, and mode-conversion amplitudes and waveforms for primary and secondary waves are modeled at variable angles of incidence. The modeled records exhibit the expected seismic-wave attenuation and dispersion phenomena but differ from the predictions of viscoelastic modeling. The key observation is that wave-propagation effects are sensitive not only to the Q-factors of the layers but also to properties not considered in conventional models: (1) elastic coupling between the internal variables, (2) body-force friction parameters analogous to fluid mobility, and (3) mechanical properties of contact zones between different rocks, such as the effective permeabilities of layer boundaries. Although challenging, these properties of layer boundaries need to be measured for earth’s media and included in the modeling of seismic waves. Another important general observation from this modeling is that the often observed broadband or near-constant seismic Q may result from superposition of the effects of multiple heterogeneities (layers) and material-property contrasts within the medium.

Research of high-speed high-performance and small-sized screw conveyors-grain loaders

Currently, agricultural enterprises are offered many conveyors of various typesfor the mechanization of loading and unloading works during cropmovement. The article presents studies of a method of increasing performance of a screw type conveyor allowing to create a small-sized design by increasing its revolutions. It investigates workmechanism, describesoperational technology of conveyors-grain and work disadvantages, namely, problematicgrain transportation over long distances along a spatial route or complication of technological scheme. Loading directly from pile may require manual labor or additional equipment. It is noted that increase in performance with increase in rotor revolutions (from 400 to 1100 rpm) occurs up to a point, after which revolutions increase, and performance decreases. In order to increase screw performance, it is necessary to accelerate material axial advance, i.e. to stretch ascending and, especially, falling material trajectorybranches at high speeds, with bulky material (grain), cast by centrifugal force to inner pipe surface, filling the grooves. Since their locationis close to each other (at 30°), surface braking layer is formed, which decreases circumferential speed component of absolute movement of grain andincreases the axial one. In order to increase screw performance, it is necessary to accelerate material axial advance, i.e. stretch ascending and, especially, falling material trajectorybranches. Further studies will contribute to finding new ways to increase speed coefficient K υ and coefficient ψ and create high-speed, high-performance, and small-sized screw conveyors-grain loaders.