Vibrations in engineering and technology

Stepanenko Serhii, Senior Researcher, Doctor of Technical Sciences, Head of the Department of Mechanical and Technological Problems of Harvesting and Post-Harvest Processing of Grain and Oilseed Crops, Institute of Mechanics and Automation of Agro-Industrial Production, National Academy of Agrarian Sciences of Ukraine, Hlevakha, Ukraine, email: Stepanenko_s@ukr.net, https://orcid.org/0000-0002-8331-4632 

Kuzmych Alvian, senior researcher, candidate of technical sciences, senior research fellow of the department of mechanical and technological problems of harvesting and post-harvest processing of grain and oilseed crops, Institute of Mechanics and Automation of Agro-industrial Production of the National Academy of Agrarian Sciences of Ukraine, Hlevakha, Ukraine, email: akuzmich75@gmail.com,https://orcid.org/0000-0003-3102-0840 

Dnes Viktor, Senior Researcher, Candidate of Technical Sciences, Head of the Department of Modeling of Technological Processes in Plant Growing, Institute of Mechanics and Automation of Agro-industrial Production of the National Academy of Agrarian Sciences of Ukraine, Hlevakha, Ukraine, email: dnes.viktor@ukr.net, https://orcid.org/0000-0002-4166-2276 

Popadiuk Ihor, Junior Researcher, Department of Mechanical and Technological Problems of Harvesting and Post-Harvest Processing of Grain and Oilseed Crops, Institute of Mechanics and Automation of Agro-Industrial Production, National Academy of Agrarian Sciences of Ukraine, Hlevakha, Ukraine, email: i-popadyuk@ukr.net https://orcid.org/0000-0001-5138-9499 

This article addresses an important scientific and practical problem in agricultural engineering: the intensification of grain cleaning and sorting processes through the use of vibrating centrifugal force fields. It has been established that traditional separation methods often fail to meet the necessary quality standards due to slight differences in the physical and mechanical properties of the components of the grain mixture. The study demonstrates that combining centrifugal fields with axial oscillations of the working surface effectively amplifies differences in particle density and aerodynamic properties, leading to more accurate separation.

The study presents an improved mathematical model of the mechanics of a single particle on the inner surface of a conical rotor performing both rotational and oscillatory motion. A comprehensive force analysis was conducted, taking into account the centrifugal inertial force, the oscillatory inertial force, the gravitational force, the normal reaction of the rotor surface, and the friction force between the particle and the material. Based on an analysis of dynamic equilibrium and the conditions of continuous contact motion, a differential equation for the particle’s displacement to the end of the rotor’s expansion was derived.

Analytical expressions were derived for determining the instantaneous and average velocities of grain material as functions of the oscillation phase. The study identified the critical conditions necessary to ensure a steady-state motion regime with periodic stops, which is optimal for high-quality separation. The quantitative influence of key kinematic parameters, in particular specifically, the amplitude and frequency of oscillations, the angular velocity of the rotor, the taper angle, and the friction coefficient, on process performance was established. The formulated recommendations provide a rigorous scientific basis for the design and modernization of high-performance vibrocentrifugal machines for grain cleaning, aimed at improving seed quality while simultaneously reducing energy consumption during post-harvest processing stages.

1. Bredykhin, V., Pak, A., Gurskyi, P., Denisenko, S., & Bredykhina, K. (2021). Improving the mechanical-mathematical model of pneumatic vibration centrifugal fractionation of grain materials based on their density. Eastern-European Journal of Enterprise Technologies, 4(1(112), 54–60 https://doi.org/10.15587/1729-4061.2021.236938 [in English].

2.  Stepanenko, S. P., Kotov, B. I., Hrushetskyi, S. M., & Rud, A. V. (2021). Matematychne modeliuvannia rukhu zernovoho materialu na poverkhni vibrozhyvylnyka za umov vvedennia yoho v aspiratsiinyi kanal separatora [Mathematical simulation of the movement of grain material on the surface of the spreader under its introduction into the aspiration channel of the separator]. Vibrations in engineering and technology, 2 (101), Р. 46–55  https://doi.org/10.37128/2306-8744-2021-2-5 [in Ukrainan].

3. Adamchuk, V., Bulgakov, V., Gadzalo, I., Ivanovs, S., Stepanenko, S., & Holovach, I. (2021). Theoretical study of vibrocentrifugal separation of grain mixtures on a sieve less seed cleaning machine. Rural Sustainability Research, 46, 116-124  https://doi.org/10.2478/plua-2021-0023 [in English].

4. Kharchenko S., Borshch Y., Kovalyshyn S., Piven M., Abduev M., Miernik A., Popardowski E., & Kiełbasa P. (2021). Modeling of aerodynamic separation of preliminarily stratified grain mixture in vertical pneumatic separation duct. Applied Sciences, 11(10), 4383  https://doi.org/10.3390/app11104383 [in English].

5. Piven, M., Volokh, V., Piven, A., & Kharchenko, S. (2018). Research into the process of loading the surface of a vibrosieve when a loose mixture is fed unevenly. Eastern-European Journal of Enterprise Technologies, 6(1(96), 62–70  https://doi.org/10.15587/1729-4061.2018.149739 [in English].

6. Kharchenko, S., Kovalyshyn, S., Linov, A., Abduev, M., Kharchenko, F., & Sirovitskiy, K. (2022). Identification of significant factors in the process of grain mixtures separation on cylindrical sieve. ТЕKA. Semi-Annual Journal of Agri-Food Industry, 22(1), 5–8 [in English]. 

7. Stepanenko, S., & Kotov, B. (2019). Theoretical research of separation process grain mixtures. Machinery & Energetics, 10(4), 137-143 [in English]. 

8. Bohatyrov, D., Skrynnik, I., & Yurchenko, O. (2019). Obgruntuvannia tekhnolohichnykh parametriv zernovoho separatora [Justification of technological parameters of the grain separator]. Design, production and exploitation of agricultural machinery, 49, 34–42  https://doi.org/10.32515/2414-3820.2019.49.34-42 [in Ukrainan].

9. Vasylkovskyi, O., Leshchenko, S., Moroz, S., & Petrenko, D. (2018). Doslidzhennia enerhoiemnosti kholostoho khodu vidtsentrovoho separatora zerna [Investigation of the energy intensity of the idle speed of the centrifugal grain separator]. Design, production and exploitation of agricultural machinery, 48, 176–183  https://doi.org/10.32515/2414-3820.2018.48.176-183 [in Ukrainan].

10. Petrenko, D. I., Leshchenko, S. M., Niedielskyi, D. S., & Bilitsenko, I. O. (2025). Matematychna model roboty pnevmohravitatsiinoho separatora zernovykh sumishei [Mathematical Model the Operation of a Pneumogravity Separator for Grain Mixtures]. Design, production and exploitation of agricultural machinery, 55, 112–120  https://doi.org/10.32515/2414-3820.2025.55.112-120 [in Ukrainan].

11. Melnyk, V., Popadyuk, I., & Stepanenko, S. (2024). Analysis of the grain cleaning method using a vibratory centrifugal approach with the utilization of a conical sieve. Scientific Collection «InterConf», 187, 330–335 [in English].

12.  Koban, Y., Vasylkovskyi, O., & Nesterenko, О. (2026). Obgruntuvannia konstruktsiinoi skhemy pnevmatychnoho zernovoho separatora [Justification of the structural scheme of a pneumatic grain separator]. Design, production and exploitation of agricultural machinery, 55, 287–297  https://doi.org/10.32515/2414-3820.2025.55.287-297 [in Ukrainan].