International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

Parametric optimization of a curved channel was made with changing the geometric shape under pre-set conditions when liquid or gas flows through it. Mathematical modelling of hydrodynamic processes was performed in curved channels of the confuser type. As a result of numerical modelling of the hydrodynamic processes, using the ANSYS Fluent CAD software product, the distributions of velocities and pressures in the confuser channel were obtained. The optimal curved channel profile was selected. based on the conditions of minimal pressure losses in the channel. The obtained results may be used in the design of the heat exchange and aerodynamic equipment.

The article presents the construction of a flexible sectional screw working body, the use of which allows to improve the performance of flexible screw conveyors with low material consumption of the working body, which reduces energy costs for the transportation process. Based on the results of static experimental studies, the nature of the change in the dependence of torque on the angle of twist of individual sections has been established.

The Stirling engine represents one of the most promising technologies for the efficient conversion of thermal energy into mechanical work, due to its ability to operate with almost any heat source and to achieve theoretical efficiencies approaching the Carnot cycle. This article aims to provide a detailed study of the Stirling cycle, the development of a mathematical model, numerical simulation using MATLAB and the analysis of the engine performance as a function of the main thermodynamic parameters, with special emphasis on applications in micro-power generation. A distinctive aspect of this study lies in the comprehensive treatment of the polynomial dependence of specific heat in all thermodynamic processes, enabling a more accurate representation of real gas behavior compared to idealized classical models. The mathematical model is formulated using the fundamental laws of thermodynamics and the ideal gas equation, as well as the well-known Schmidt model for the analytical description of pressure and volume throughout the cycle. A numerical simulation is then performed in MATLAB, where the work per cycle is calculated, p–V and T–s diagrams are generated, and the theoretical efficiency is evaluated for different operating temperatures and pressures. The simulation results show that increasing the temperature difference and average gas pressure significantly increases the mechanical output of the engine and the power output, while an efficient regenerator significantly improves the overall performance and brings the engine closer to Carnot efficiency. The study shows that the Stirling engine has significant potential for sustainable power generation systems, while the developed modeling and simulation framework provides a solid foundation for further experimental development and design optimization.

This study presents the comprehensive design and architectural modeling of a robotic-based multi-packaging machine developed for high-speed and high-precision packaging processes. The system integrates a Delta robot-based pick-and-place unit, advanced servocontrolled horizontal packaging modules, and a modular conveyor design engineered for multi-product stream transfer. This work investigates the core operational challenges, including product flow management, optimized grouping strategies, dynamic conveyor synchronization, coordination of multi-axis servo movements, and the system’s overall operational efficiency. The results indicate that the developed system operates with high stability, achieves superior precision, and significantly enhances production throughput by providing automatic parameter optimization based on product variety, thereby aligning with modern Industry 4.0 requirements.

Current diagnostic approaches, although widely applied, often fail to identify defects at the earliest stages of their development. This limitation not only reduces operational efficiency but also results in unplanned downtime, costly repairs, and increased risks to both personnel and the environment. Unlike conventional techniques, AE enables real-time detection of microstructural changes associated with defect initiation and provides valuable information about their severity and rate of progression. Obtained results confirm that the AE method allows reliable identification of early-stage defects, enabling the prediction of their further development and the assessment of the technical condition of critical engine components. These findings demonstrate that AE-based monitoring can serve as an effective diagnostic and prognostic tool, enhancing the safety, energy and environmental efficiency. The study involved placing AE sensors on specific areas of the engine. The engine was then operated in various modes, with the AE system recording AE signals. The results were analyzed (express analysis) to identify the sources of the AE signals.

An experimental model of a safety clutch has been developed and manufactured, which will improve the efficiency of screw conveyors by increasing the axial displacement of the driven half-clutch with a jammed working body, while reducing dynamic loads during overload. When conducting a multifactorial experiment to determine the moment of operation T of the safety clutch of a screw conveyor, the variable factors were the angle of inclination of the working body to the horizon α, the rotation frequency of the screw working body n, and the time of increase in the resistance moment То. Based on the results of experimental studies, corresponding regression equations, response surfaces, and their two-dimensional cross-sections were constructed to establish the influence of controlled factors on the moment of operation of the safety clutch under extreme operating conditions. The obtained regression equation can be used to determine the moment of clutch engagement during the transportation of bulk and lump agricultural materials by a screw conveyor.

The article presents an algorithm for solving the forward kinematics problem for a multi-link manipulator robotic system model based on the matrix method of attached coordinates.

In this paper are presented results of the isentropic analysis related to the cylinders, segments and whole three cylinder steam turbine from the conventional power plant. In the analyzed steam turbine Low Pressure Cylinder (LPC) is the dominant mechanical power producer of all cylinders – it produces 130.16 MW of mechanical power in the real expansion process and it can produce 142.80 MW of mechanical power if the expansion conditions are ideal. The satisfactory isentropic performance of the whole High Pressure Cylinder (HPC) is a combination of two segment’s isentropic performance – one of these segments show extremely good isentropic performance (Seg2), but another segment (Seg1) shows very poor isentropic performance. Both Intermediate Pressure Cylinder (IPC) segments (Seg3 and Seg4) show similar isentropic performance, what result with the balanced IPC operation. LPC has an isentropic efficiency of 91.15%, what is the highest isentropic efficiency of all cylinders from the observed steam turbine. Whole observed steam turbine has an isentropic efficiency of 88.42% what is better isentropic performance in comparison to similar steam turbines from conventional power plants.

In line with the Paris Climate Agreement, the European Union’s Green Deal targets achieving net-zero greenhouse gas emissions by 2050. Accordingly, research and development efforts to minimize the carbon footprint of industrial production processes and products have gained increasing importance, particularly in light of border carbon adjustment mechanisms and compliance requirements. Therefore, reducing the environmental impact of products already in use through innovative design and development is a critical priority. This study addresses these challenges by proposing a novel waste heat recovery (WHR) system integrated into a gas-fired (natural gas and LPG) commercial cooking oven prototype. The main objective is to enhance energy efficiency and reduce emissions by reusing exhaust gases (CO, CO₂ , etc.) generated during cooking. The recovered waste heat is used to preheat the air–fuel mixture, lowering fuel consumption and contributing to energy optimization and environmental sustainability. Inspired by the Exhaust Gas Recirculation (EGR) concept used in automotive applications, the proposed system was adapted for commercial cooking appliances. Simulation studies guided the design process, enabling the development of an original WHR system through university–industry collaboration. The findings highlight the potential of waste heat recovery in commercial cooking ovens to reduce carbon emissions, improve fuel efficiency, and support the transition towards sustainable industrial practices.

Roll leveling is a technological process of metal forming, used to minimize the flatness of sheet plates and reduce the level of residual stresses. The report presents the design of a 13-roll leveler for straightening sheet plates of complex configuration. The straightening precision is directly affected by the stiffness of the leveler housing. To determine the characteristics and patterns of deformation, the equivalent finite element model of the leveler housing are established and then the features of stress and strain about the leveler housing are studied.

Microbial fuel cells (MFCs) have significant potential for sustainable energy production and waste management, but despite this, they are still not widely commercialized due to several main reasons, such as relatively low power generation, technical challenges, scalability, and others. In the present study, we tested the possibilities for storage and utilization of energy from our developed green waste composter with cogeneration of energy. The composter consists of 24 stacked solid phase microbial fuel cells. The generated energy was increased through a voltage boost converter and used for charging batteries, power banks, and low-energy consumption devices. The composter demonstrated stable operation, and the obtained results regarding the storage and utilization of the energy generated by it are promising for its commercialization.

The objective of this study is to numerically investigate the fluid flow and heat transfer performance of a finned-tube heat exchanger (FTHEX). The analysis focuses on the implementation of three vortex generator (VG) configurations: rectangular winglet (RW), delta-winglet upstream (DWU), and delta-winglet downstream (DWD) — mounted on the fin surface in a “common-flow-up” orientation. Attack angles of 15°, 30°, and 45° are considered for each VG type to evaluate their impact on the heat exchanger’s heat transfer potential and friction losses. The air-side Reynolds number, based on the outside tube diameter, was varied within the range 684 ≤ Re ≤ 1532. The results indicate that among the tested configurations, the RWP setup with an attack angle of 45° achieves the highest enhancement in the airside Nusselt number, with improvements ranging from 20% to 45% compared to the reference configuration, but at the expense of a higher pressure drop. For attack angles αvg = 15° and αvg = 30°, the highest overall performance (TPF factor) is achieved with the rectangular winglet configuration across the entire Reynolds number range. At an attack angle of αvg = 45°, the heat exchanger with downstream delta winglets shows higher TPF values compared to the other configurations, except at Re = 1278.