Cylindrical Drum Research Articles

Development of a Cost-Effective Coconut Dehusking Machine

This study aimed to develop an affordable mechanized solution to address this challenge.A coconut dehusking machine prototype was designed, fabricated, and tested. It consists of a rigid steel frame, two counter- rotating cylindrical drums fitted with spikes, an electric motor, a V-belt drive system, and a control panel. Components were sized through structural and mechanical calculations. Fabrication utilized locally sourced materials within a 250,000 NGN budget.Testing showed the machine achieving 90% dehusking efficiency at 120 nuts/hour. Operational costs are minimized through a 1.5HP electric motor. Finite element analysis verified the structural integrity of machine components under operational loads.Results indicate the objectives of developing an affordable and efficient mechanized solution were achieved. Widespread adoption has the prospect of enhancing coconut farming viability, boosting rural livelihoods, and promoting agro- industrialization in Nigeria through coconut value addition. This study demonstrates how appropriately designed technology can support sustainable agricultural development in resource-constrained communities.

Only Pottery Drums in the Stone Age?

Hundreds of possible prehistoric pottery drums made in Central Europe, mainly from the Late Neolithic (especially the TRB culture) have been found. Their forms vary from funnel-shaped, goblet to hourglass. It is not difficult to imagine equivalent or alternative forms of drums made from hard plant tissues, which are missing in the archaeological record during these or even other periods. Aside from a thought experiment based on archaeological knowledge, experimental and experiential research is presented here with three main examples of wooden drums – a simple frame drum from a branch imaginable since the Palaeolithic, a cylindrical double-headed drum made from a log with a rotten inside, and a wooden alternative to a TRB goblet drum that is compared to a ceramic replica of the same type of TRB drum in terms of material characteristics, technology, tools, skill, productions costs, time requirements and durability. The experience and results prove that simple frame drums are the fastest and the easiest option, followed by cylindrical drums made from logs, however production costs of wooden vessel drums greatly exceed those of pottery ones. Thin walls make ceramic drums much worse in terms of manipulation, playing and durability, but fairly better in clear and loud sound production. The presented examples are closely related to Central European prehistory, but they may serve as valuable analogies to other geographical or cultural contexts as well.

CHARACTERISTICS OF THE DESIGNS OF MODERN PICK-UP TRUCKS AND EFFICIENCY OF THEIR WORK IN THE PROCUREMENT OF STEM FORAGE FOR THE PRODUCTION OF HIGHLY NUTRITIONAL PROTEIN-VITAMIN PASTE AND PULLEY

In the agro-industrial complex of Ukraine, all types of leafy fodder are used, which make up almost 50-60% of the cost price of livestock products. The choice of existing harvesting technologies depends on the required type of fodder, the method of harvesting the cultivated crop, the available number of technical means and machines in the farm. The use and introduction of new energy-saving means in the conditions of an acute energy crisis, which is currently observed in almost all branches of the national economy, especially in the technologies of harvesting stem fodder, is of particular importance. One of the directions for solving the mentioned problems is the use of pick-up trucks in the technological process of harvesting hay, haylage, and green mass. The research methodology is based on the application of methods of analysis and analogy, analytical methods, methods of higher mathematics and numerical calculations. When studying and comparing the design and technological parameters of pick-up trucks, it has been found that they mainly consist of a frame, a trailer, a chassis, a pick-up with a shredder, a body, an unloading device and a hydraulic system. For additional unloading of fodder in the feeder, pick-up trucks are made with a dosing device. As for the undercarriage of such machines, it can be single-axle, tandem or three-axle with forced control, depending on the load capacity. The bodies are mostly welded, in most models they are somewhat narrowed down. They can have folding or removable upper parts of the sides. The upper part of the body is covered with an awning or longitudinal synthetic ropes to prevent loss of grass mass in case of overflow. Mass pick-up is carried out according to the classic scheme, thanks to drum-finger pick-ups of different grip widths in the range of 0.55 - 2.1 m. It is noted that most models use a simple and reliable rotary feeder. This is a cylindrical drum on the surface of which curved fingers are fixed, thus forming a star-like shape. The number of fingers around the drum varies from 2 to 9, depending on the diameter. This design of the feeder allows it to be used not only in pick-up trucks, but also in press pick-ups. The rotary feeder differs in length from 1470 to 2000 mm and diameter from 600 to 880 mm, the number of rows of fingers, their design (length of the finger and the shape of the line of the working surface) and the method of mounting on the drum. The effectiveness of pick-up trucks in harvesting stem fodder for the production of highly nutritious protein-vitamin paste and pulp is studied. The dependence of changes in the operational productivity of pick-up trucks is established, which takes into account the time spent on eliminating technological violations of the work process, performing periodic maintenance operations, converting or completing the unit, and eliminating technical malfunctions.

Substantiation of the methodology for calculation of rope-capacity cylindrical drums of mine hoistmachine

Purpose. To develop a simplified calculation method for the strengthened split cylindrical drums of mine hoisting machines of the TsR-6.75x6.2/1.95 type. To evaluate the application of the method for calculating the drum of a hoisting machine of a complicated design by averaging the elements. The methods. The drum structure of a mine hoisting machine is divided into ten nodes, eight of which include the shell, frontal, rib strengthening and brake discs (end nodes) and two more – the shaftwith hubs and bearing supports. Based on the analysis of the machine's operation, including an assessment of its stiffness under different types of load, simplified models are created for each component. The original drum assemblies are replaced with simplified ones in order to perform a general calculation to determine the maximum axial displacement of the brake disc edges. Findings. Based on the analysis of the mine hoisting machine operation, averaged models of hoist components were developed and axial displacements were successfully calculated for a simplified drum design. The originality. The error of the simplified calculation method, in particular, the method of averaging with increased thickness of the lobes, which allows obtaining more accurate results for complex structures, is estimated Practical implementation. Due to the need to increase the depth of mining, which leads to the need to expand the dimensions of the drum and complicate its design. In this case, the resource intensity of calculating the axial displacement of brake discs increases. This is necessary for the introduction of disc brakes. However, this complicates the use of standard mid-level computer-aided design tools due to the increase in the size of the finite element mesh, which makes its use impractical. The methodology can be used for mine hoisting machines of the following types TsR-6.75x6.2/1.95 with a split drum, 6750 mm in diameter and 6200 mm wide (of which 1950 mm is the interchangeable part), providing accurate calculations of brake disc edge displacements. This approach is particularly useful for use in mid-range software packages such as SolidWorks Simulation, eliminating the need for resource-intensive software.

Analytical review of methods for determining the parameters of the groove profile of cable drums

Purpose. The primary goal of this study is to analyze current methodologies aimed at significantly improving the efficiency of using drums of mine hoisting machines and reducing the wear of hoisting ropes. The methods is based on the analysis of scientific works by leading experts in the field of mining engineering specializing in the development of mine hoisting machine designs. The literature review includes theoretical and practical aspects of drum design, analysis of different approaches for their rope capacity optimization, and methods to reduce rope wear during operation. Innovative technical solutions proposed in the works of domestic and foreign scientists are studied. Findings. The analysis of scientific works in the field of mine hoisting machines revealed certain shortcomings in approaches to designing and optimizing drum rope capacity. Often, the impact of dynamic loads and material wear during operation, as well as the specifics of drum operation in various mining conditions, is overlooked. This leads to increased risks of breakdowns and reduced safety of hoisting machines. Therefore, there is a need to develop new methodologies that take these aspects into account, ensuring improved quality and reliability of mine hoists. As a result of the study, an innovative drum design with a variable drum diameter was developed, allowing for increased rope capacity and reduced rope wear. The originality. It lies in the formulation of an optimization problem aimed at improving the design parameters of cylindrical drums for mine hoisting machines. This includes the development of innovative algorithms for determining the optimal characteristics of rope capacity, taking into account dynamic and safety factors. Practical implementation. The new drum design developed in the study significantly increases rope capacity, which is a critical aspect for enhancing the efficiency of mine hoisting machines. The optimization of the drum design also contributes to reducing energy consumption during operation, ensuring safer operation of hoisting machines.

Analysis of the problems of using disc brakes in the complex of long drums of mine hoists with increased rope capacity

Purpose. After analysing the current literature in the field of mine hoisting, to determine the prospects for the use of disc brakes in a complex of mine hoisting machines with increased rope capacity with a long cylindrical cutter drum. To identify the problems associated with the end runout of the sheath and an increase in the deviation angle that arise when operating drums with a long casing in order to optimise their use. The methods. The study identifies the problems of using disc brakes in combination with long drums of increased rope capacity, as well as the associated increase in the value of the deviation angle and the length of the rope string. A computer experiment was carried out to find the dependence of the end runout of the sheath on its length under the action of a steady external pressure modelling the operation of a coiled rope, using the example of the sheath of the drum TsR-6.75×6.2/1.95. Findings. The article considers the problem of stiffness of long drums of hoisting machines, the increase in length of which occurs due to the increase in the depth of extraction, as well as the use of disc brakes in such hoisting machines. A computer experiment has been conducted to determine the dependence of face runout on the length of the hoisting machine drum shell. Thus, with the lengthening of the shell, the end runout increases, which can interfere with the safe operation of the disc brake. The originality. For the first time, a calculation methodology for determining the axial stiffness of long drums of mine hoists with increased rope capacity was developed and substantiated using the example of the drum of the TsR-6.75×6.2/1.95 machine with the help of the SolidWorks and MathCAD software complex. Generalisation of data on the relationship between drum length and deviation angle, which are critical for the safety and efficiency of mine hoists. Practical implementation. The implementation of the methodology will solve the problems with the use of disc brakes in the complex of mine hoists with long cylindrical drums of increased rope capacity, namely, with the end runout of brake discs, as well as an increase in the value of the deviation angle, increasing the efficiency and safety of mine hoists. This will eliminate the need to install additional support supports when lengthening the rope string to prevent longitudinal and, as a result, transverse vibrations. Ensure more stable and safe operation of mine hoists by optimising the design and braking systems.

Factors Affecting the Formation the Carbon Structure of Coke and the Method of Stabilizing Its Physical and Mechanical Properties

The raw materials (coals different stages of metamorphism) and technological factors (period and temperature) of the coke-making that determine the carbon structure of blast furnace coke, and its physical and mechanical properties are analyzed. The change granulometric composition of the coke as a function of the coal batch properties is described in detail. The installation determines the possibility of influencing the carbon structure of coke, its granulometric composition in its production in order to increase the yields of the most valuable fractions, and improving its quality characteristics to achieve high-performance blast furnaces. Analysis of the results indicates that, with no changes in the coking conditions, the granulometric composition depends significantly on the ash content and packing density of the coal batch. Research has shown that the petrographic composition of the coal batch also affects the structure and size of the coke. The closest relationship is established between the magnitude of the fusinized components ΣFC and the output of the coke fractions 80–60 mm, 40–25 mm, and <25 mm. The method of mechanical treatment and stabilizing of blast furnace coke is proposed, which includes the improvement of the initial indexes of its quality M25, M10, and class >80 mm in continuous or periodically working open or closed industrial cylindrical oblique stabilizer drum.

The effect of calcium hydroxide addition on enhancing ammonia recovery during thermophilic composting in a self-heated pilot-scale reactor

A modified outdoor large-scale nutrient recycling system was developed to compost organic sludge and aimed to recover clean nitrogen for the cultivation of high-value-added microalgae. This study investigated the effect of calcium hydroxide addition on enhancing NH3 recovery in a pilot-scale reactor self-heated by metabolic heat of microorganisms during thermophilic composting of dewatered cow dung. 350 kg-ww of compost was prepared at the ratio of 5: 14: 1 (dewatered cowdung: rice husk: compost-seed) in a 4 m3 cylindrical rotary drum composting reactor for 14 days of aerated composting. High compost temperature up to 67 °C was observed from day 1 of composting, proving that thermophilic composting was achieved through the self-heating process. The temperature of compost increases as microbial activity increases and temperature decreases as organic matter decreases. The high CO2 evolution rate on day 0–2 (0.02–0.08 mol/min) indicated that microorganisms are most active in degrading organic matter. The increasing conversion of carbon demonstrated that organic carbon was degraded by microbial activity and emitted as CO2. The nitrogen mass balance revealed that adding calcium hydroxide to the compost and increasing the aeration rate on day 3 volatilized 9.83 % of the remaining ammonium ions in the compost, thereby improving the ammonia recovery. Moreover, Geobacillus was found to be the most dominant bacteria under elevated temperature that functions in the hydrolysis of non-dissolved nitrogen for better NH3 recovery. The presented results show that by thermophilic composting 1 ton-ds of dewatered cowdung for NH3 recovery, up to 11.54 kg-ds of microalgae can be produced.

Effect of surface roughness and blade material on the performance of a stationary Savonius wind turbine under different operating conditions

The Savonius wind turbine is a vertical-axis wind turbine invented in 1930s consisting of a cylindrical drum with semi-circular blades attached to the drum. It is popular for its simple design, low costs, and self-starting ability, making it feasible for rural areas. As a rotating device, the blade is considered an important component of the Savonius turbine because it captures energy from an omni-directional wind flow and converts it into mechanical/electrical energy. Blade corrosion can cause a surface degradation which affects the blade's aerodynamic and structural performance. The relation between surface roughness and turbine performance has been addressed in various studies; however, most of these studies focused on horizontal-axis wind turbine. This study analyzed the performance of a static Savonius turbine using a three-dimensional (3D) computer simulation at different blade angle positions through a one-way fluid–structure interaction in terms of static coefficients, von Mises stresses, and deformation with different surface roughness at different wind velocities. The simulation reveals that the position with highest static torque coefficient is when the turbine is resting at 15° with respect to the flow direction. The flow velocity increases the performance; however, the surface roughness deteriorates the flow and decreases the static coefficient. The simulation herein predicts no structural failure, but different materials exhibit different maximum stress and deformation showing the importance of material selection in the turbine blade development. The findings from this study helps to identify a suitable material for the development of the Savonius turbine from a material point of view to minimize turbine downtime and potentially save cost.

The Organology of Rotenese Musical Instruments According to the Hornbostel-Sachs Classification System

This article aims to propose a classification of Rotenese traditional musical instruments based on the Hornbostel-Sachs (the H-S) method. The author conducted this ethnographic field research on the island of Rote, East Nusa Tenggara Province, from 2015 to 2016. The seven existing Rotenese traditional musical instruments analyzed in this article are: 1) meko ai or the meko o (the wooden or the bamboo xylophone); 2) the meko besik or the meko lilok (the hanging iron or brass gongs); 3) the meko besik or the meko lilok (the iron or brass metallophone); 4) the labu kici or the labu so’e (the single-headed, bowl-shaped drum); 5) the tambur or the labu (the single-headed, long cylindrical drum); 6) the bitala (the crash cymbals); and 7) the sasandu (the heterochord tube-zither). The only Rotenese traditional musical instrument that is not discussed in this article is kianuk, the two-holed bamboo flute, approximately ten centimeters long. This instrument does not exist anymore. The four aspects discussed in this article are 1) the construction, 2) the materials, 3) the ways of playing, and 4) the size of the instruments. Information was gathered from interviews with some key persons and through photography and video recording. This research acknowledges some limitations; for instance, providing exact information is challenging and limiting in the absence of a standard for meko tuning and making. Therefore, the information given here about the size, the material, the tuning, and the note intervals is an approximation.

Non-destructive interrogation of nuclear waste barrels through muon tomography: a Monte Carlo study based on dual-parameter analysis via GEANT4 simulations

The structural characterization of the nuclear materials constitutes an indispensable aspect that necessitates a careful transportation, a limited interaction, and under certain circumstances an on-site investigation for the nuclear fields including but not limited to nuclear waste management, nuclear forensics, and nuclear proliferation. To attain this purpose, among the promising non-destructive/non-hazardous techniques that are performed for the interrogation of the nuclear materials is the muon tomography where the target materials are discriminated by the interplay between the atomic number, the material density, and the material thickness on the basis of the scattering angle and the absorption in the course of the muon propagation within the target volume. In this study, we employ the Monte Carlo simulations by using the GEANT4 code to demonstrate the capability of muon tomography based on the dual-parameter analysis in the examination of the nuclear waste barrels. Our current hodoscope setup consists of three top and three bottom plastic scintillators made of polyvinyl toluene with the thickness of 0.4 cm, and the composite target material is a cylindrical nuclear waste drum with the height of 96 cm and the radius of 29.6 cm where the outermost layer is stainless steel with the lateral thickness of 3.2 cm and the filling material is ordinary concrete that encapsulates the nuclear materials of dimensions 20×20×20 cm3. By simulating with a narrow planar muon beam of 1×1 cm2 over the uniform energy interval between 0.1 and 8 GeV, we determine the variation of the average scattering angle together with the standard deviation by utilizing a 0.5-GeV bin length, the counts of the scattering angle by using a 1-mrad step, and the number of the absorption events for the five prevalent nuclear materials starting from cobalt and ending in plutonium. Via the duo-parametric analysis that is founded on the scattering angle as well as the absorption in the present study, we show that the presence of the nuclear materials in the waste barrels is numerically visible in comparison with the concrete-filled waste drum without any nuclear material, and the muon tomography is capable of distinguishing these nuclear materials by coupling the information about the scattering angle and the number of absorption in the cases where one of these two parameters yields strong similarity for certain nuclear materials.

Substantiating the methods for calculating the split cylindrical drums of mine hoisting machines with increased rope capacity

Purpose. A simplified calculation method development for strengthened split cylindrical drum structures of the mine hoisting machines of the TsR-6.756.2/1.95 type. Methodology. The drum structure for the mine hoisting machines is conventionally divided into several nodes. A simplified averaged model is constructed for the nodes consisting of the shell, frontal, rib strengthening and brake discs (end nodes) based on the analysis of their operation, in particular, the stiffness analysis under different loads. After that, when assembling, the initial drum nodes are replaced with simplified ones and a so-called simplified model for the whole drum is constructed, as well as the displacements of the brake disc edges are determined. Findings. The simplified models for drum nodes have been created based on the analysis of their operation, and then the displacements of the whole drum simplified model have been calculated. Originality. The simplified calculation method error has been estimated: the method of averaging with increased thickness of the frontals. Practical value. For the TsR-6.756.2/1.95 hoisting machine with a drum diameter of 6750 mm, a drum width of 6200 mm and an adjustable part width of 1950 mm, with a groove cutting pitch of 51 mm and a maximum lifting depth of 1477 m, it has been determined that the maximum axial displacements for brake disc edges of the jammed and adjustable parts are 0.854 and 1.921mm, respectively. A simplified calculation method has been developed for strengthened split cylindrical drum structures of the mine hoisting machines of the TsR-6.756.2/1.95 type, available for use in middle-class packages such as SolidWorks Simulation.

Experimental Study on Direct Harvesting of Corn Kernels

The mechanical harvesting of corn has always been a problem for the development of the corn industry. In the present investigation, a tangential flow–transverse axial flow threshing test system was designed based on the 4YL-4/5 harvester. The structure design was modular, and the threshing drum and other key parts could be changed, or the technical parameters could be adjusted according to the needs. Thus, the system becomes suitable to carry out the threshing test of various grains. In this paper, two kinds of systems, a cylindrical plate-tooth mixed row threshing drum and a full cylindrical threshing drum, were designed. Using the same materials and technical conditions, a comparative experiment of the corn grain harvest was carried out to explore the mechanical–technical conditions and methods to reduce the grain breakage rate of corn’s direct harvest.The results showed that the threshing ability and adaptability of the cylinder with a plate-tooth mixed arrangement structure were higher than those of the full cylinder arrangement structure. It was also found that for a higher moisture content (above 28%) of the maize ear, the grain breakage rate met the national standard. On the other hand, the cylinder with a plate-tooth threshing drum can support a wider range of moisture contents and drum peripheral velocities than the full cylinder threshing drum. Within the range of all tested moisture contents and drum peripheral velocities, the minimum grain breakage rate of the full cylinder tooth drum was 3.7%, and the minimum grain breakage rate of the cylinder with the plate-tooth threshing drum was 1.5%, which means a reduction of 59.5% of the breakage rate was achieved.

Mixing Enhancement of Mono-Disperse and Bi-Disperse Particles in a Cylindrical Drum Mixer Using Discrete Element Simulations

Mixing Enhancement of Mono-Disperse and Bi-Disperse Particles in a Cylindrical Drum Mixer Using Discrete Element Simulations

Study of classification processes of various bulk geomaterials in a hydrodynamic environment using laboratory models of counter-current drum separators

The paper presents the results of studying separation processes of various mineral particles of different density in a hydrodynamic (water) environment in three laboratory models of counter-current drum separators with cylindrical, conical and multifaceted drums. Research results have shown that compared to cylindrical and conical drum separators, the multifaceted separator is most effective in separating and refining in a hydrodynamic environment. The high recovery of heavy minerals in the concentrate proves this fact.

Development of a manual egusi (Citrulus Vulgaris) washing machine

Egusi is an important oil seed plant used in the food industry. However, the washing of egusi seeds after harvest has been a major challenge to the egusi farmers in Nigeria. The washing of egusi seeds after harvest is locally done by the use of basket containing unwashed egusi seeds submerged inside water and washed with hand to remove the slime and dirt which is labour intensive and time consuming. A manual egusi (Citrulus Vulgaris) washing machine was developed to help egusi farmers in washing of egusi seeds after manual pod cracking and seeds scooping. The average length, width, thickness and sphericity of 100 egusi seeds were first determined to be 15 mm, 8.8 mm, 2.06 mm and 0.43 mm and used in the machine design. The machine was designed and fabricated using available materials and it consist of five major components which are; cylindrical drum, perforated drum, roller, water tank and frame with a capacity of 32.14kg/batch. The machine was evaluated to have 75.3% washing efficiency, 0.08% percentage loss, and 0.0% damaged egusi respectively.

The effect of side walls on particles mixing in rotating drums

In this paper, we study the effects of the presence and shape of side walls and of the overall length of rotating cylindrical drums on the mixing of particles with differing sizes by application of the discrete element method (DEM). By varying the semi-axis of the spheroidally shaped side walls and the length of the overall drum, we observe the formation of circulation patterns near the side walls. Although there is a vast amount of literature studying mixing regimes in rotating drums, little is known about the effect of the side walls of the drum on particle mixing. The results of our study demonstrate that introducing curved side walls induces a strong circulation pattern near these side walls, but has, paradoxically, a negative impact on mixing and actually promotes segregation. The cause for this segregation is the difference in velocity of differently sized particles near the curved side walls. Large particles accumulate at the curved side walls, whereas small particles move away from the curved side walls. When the length of the drum is increased, the overall effect of the side walls is decreased, although it does remain observable, even in very large drums.

Practical aspects of the implementation of the resource conservation system at various stages of soil cultivation and sowing in the difficult soil and climatic conditions of Central Ukraine

Purpose. Justification of constructions of agricultural machines intended for the implementation of systems of soil protection and energy-saving technologies in the soil and climatic conditions of Central Ukraine. Methods. Analytical and monographic. Results. The results of multi-year field studies of the implementation of traditional and resource-saving technologies in the conditions of the Forest-Steppe zone of Ukraine are analyzed. It was determined that the system of soil cultivation in a specific farm should be chosen in accordance with the structure of crops, taking into account the biological requirements of cultivated crops, the topography of the fields, the physical and mechanical properties of the soil, the presence and depth of the layer of high compaction. It is also necessary to evaluate the economic expediency of farm expenses for different tillage options for each field for crop rotation. The work proves the necessity of introducing into production the following tillage and seeding machines developed by scientists of the National Technical University: a roller-shredder of harvest residues with optimized parameters of a cylindrical drum, a family of multi-layer soil looseners, chisel tools for high-quality no-till soil cultivation with various physical and mechanical properties, elastic supports of cultivator paws with adjustment of vibration characteristics depending on the type and condition of the soil, optimal design of the section for direct sowing of grain crops with local application of liquid fertilizers. The implementation of the proposed technique in the technological processes of growing agricultural crops should become the basis for the introduction of soil protection and energy-saving. Conclusions. The proposed technique for the technological processes of growing agricultural crops for the introduction of soil protection and energy-saving technologies allows you to reduce fuel consumption by more than half, from 79.5 l/ha under traditional technologies to 39 l/ha under the developed improved farming system built on the principles of No-Till, and the device for applying liquid fertilizers as part of the modernized section of the Terra Nova 1714 planter allows this operation to be carried out simultaneously with sowing to a depth that is 10–20 mm greater than the depth of the seed placement. Keywords: resource conservation system, tillage, shredder roller, soil loosener, chisel tool, elastic rack.

The natural frequency of drum-deployed thin-walled open tubular booms

Thin-walled tape springs are extended from cylindrical deployment drums to support instruments and sensors in a cantilevered manner on spacecraft. Attaching tape springs onto the deployment drums results in a partially flattened and partially restrained cross section, which is far from the ideal case of a fixed-free beam. The consequence is a more compliant root condition that has the potential to couple and amplify on-board microvibrations with the natural frequency of the extended instrumentation. In this paper it is shown that an Euler–Bernoulli beam model can be used to calculate the natural frequency of drum-deployed tape springs using elastic boundary conditions to represent the root condition. A Finite Element (FE) model and experimental data are used to validate the beam model’s correctly predicted relationships between the natural frequency and tape spring length, f1,Res.∝L−1.5, and its rotational stiffness, f1,Res.∝krot0.5. For the investigated beryllium copper tape springs the FE model and beam model are in excellent agreement with experiment, with the error <10%. For carbon fibre epoxy tape springs there is also strong agreement between the FE model and experiment, and approximately 10%–20% error with the beam model. On a scale from a hinged beam to a fixed-free beam, the non-dimensionalised beam equation reveals that the drum-deployed tape springs are close to the hinged beam end of the scale. Two stiffening methods are proposed to increase the stiffness of the tape springs, and hence move the tape springs towards being a fixed-free beam.

DETERMINATION OF THE MODE OF FUNCTIONING OF THE CENTRIFUGAL-GRAVITATIONAL SEPARATOR OF THE GRINDING DEVICE

The peculiarity of harvesting legumes is the need to process their heap on grater devices with subsequent separation. To improve the technical and economic performance of seed heap processing equipment, it is advisable to combine wiping and separation operations by combining a grater working body and a separating rotating sieve of cylindrical or conical shape. The analysis of influence of geometry of rotary sieve drums allows to define the rational form and parameters of work of the separating device which will provide the necessary quality of seed material. Analysis of the literature on the processes of sieve separation of grain and seed mixtures showed the advantages of centrifugal separators with a rotating sieve surface. Improving the efficiency of separation of mixtures by rotary sieves is achieved by the simultaneous use of centrifugal, Coriolis and gravitational forces. The aim of the study is to increase the efficiency of separation of seed heaps of legumes after treatment with a grater device by determining the trajectory of the seeds along the rotational surfaces. Earlier, the authors developed a grater-separating unit in which a cylindrical perforated drum is used to remove unworn seeds. This design does not use the surface of the sieve effectively enough. To increase the uniformity of the load on the steaming surface of the rotary drum, it is advisable to reduce its area in the direction of seed movement. To do this, use a conical separating surface to reduce the radius of the cone in the direction of movement of the material. When considering the movement of a particle, it is represented as a material point with mass m moving along a conical surface that rotates around a vertical axis. As a result of theoretical researches the dependence which defines time of stay of a particle on a sieve depending on a coordinate (length of a generating cone) is received. A graphical interpretation of this dependence for certain values of design parameters is also presented. As a result of research, it was found that increasing the residence time of the material on the sieve due to the use of a conical surface increases the yield of pure seeds, and also contributes to the uniform loading of the sieve surface, which improves the quality of the source material.