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

This study proposes a mathematical model for design and optimization of a hydrogen supply chain, covering all stages of the life cycle – feedstocks, production, storage, distribution, end-use in the transport sector. The developed methodology integrates different hydrogen production technologies and takes into account environmental, economic and social impacts in order to identify the most efficient and sustainable configuration. The focus in this work falls on hydrogen production by steam reforming of methane and hydrogen production by electrolysis of water in hydrogen refueling stations. The mathematical model is formulated in terms of MILP programming and can be solved using the GAMS software product. The aim is to find an optimal balance between economic efficiency, environmental sustainability and social impact by using weighted coefficients (weights). The proposed concept provides a decision-making tool for planning hydrogen infrastructure in line with European decarbonization and sustainable transport goals.

This paper presents a practical application of the authors’ universal algorithm for optimal planning in combinatorially complex problems, using the strip cutting problem in the production of electric-welded pipes as a case study. The algorithm is based on a synthesis of duality theory and an iterative approach. It implements a mechanism for selecting or generating new promising alternatives based on dual estimates, enabling the identification of a near-globally optimal solution without exhaustive enumeration. This holds true under conditions of both complete and partial a priori determinacy of the solution set.

This study investigates the application of Computational Fluid Dynamics (CFD) to optimize the flow performance of a fire monitor. Geometric modifications were implemented and analyzed using CFD simulations, comparing the original design with a modified version. The results demonstrate that the optimized design achieved a notable increase in outlet velocity (0.76 m/s) and a significant reduction in internal pressure (13,328 Pa). These findings highlight the potential for design simplification to improve operational efficiency and reduce costs.

The integration of engineering support tools is essential for the efficient modeling, simulation, and optimization of complex technical systems. This paper presents a dynamic model of a micro-combined heat and power (mCHP) system, developed to validate the feasibility of integrating various computational environments. The approach leverages modular architectures, enabling seamless data exchange between distinct software platforms, thus supporting both detailed thermodynamic analysis and real-time performance optimization. The flexibility of this approach allows for the inclusion of diverse analytical frameworks, including neural network-based optimization, data-driven control strategies, and alternative programming languages, without being limited to a single computational tool. This adaptability makes the proposed architecture particularly suitable for evolving engineering applications, where rapid prototyping and iterativ e refinement are critical. The study highlights the potential of such integrated environments to enhance the design and operational efficiency of energy systems, providing a scalable foundation for future expansions.

Agricultural machinery operates in special soil-climatic and dynamic conditions of Georgia. Its working parts are constantly exposed to alternating dynamic loads, abrasive particles in the cultivated soil, exposure and slope of the relief, high humidity, high radiation, etc. All these factors cause intensive wear of their working parts and therefore such machines are subject to special reliability requirements. In addition, agricultural machinery must be highly reliable due to the fact that harvesting is carried out in a short time and failures of such machines lead to significant losses of agricultural products. To improve the reliability and performance of worn parts, we have developed a new, resource-saving, alternative technology using spark alloying. Theoretical foundations and methods for optimizing the adhesion strength of metal coatings obtained by spark alloying have also been developed using multifactorial experiment planning. To optimize the process of restoring worn parts, the Box-Wilson steep climb method was u sed. The work was supported by the Shota Rustaveli Georgian National Science Foundation FR – 23-1855.

In this issue the main new opportunities in MAGMASOFT® 6.1 /last version of software package MAGMASOFT/ are presented and illustrated. The presentation will introduce you in all general innovations as general innovations in geometry perspective, new options for heat treatment of castings, new possibilities in continuous casting and a new innovation – MAGMA ECONOMICS. With the last option you can now also keep an eye on costs and emissions. With MAGMA ECONOMICS you can add a decision criterion to your decision base. Calculate the costs or look at the carbon footprint and make more informed decisions.

The latest version of MAGMASOFT software package – MAGMA6.1 is used to simulate and optimize a casting formation. The alloy AlSi7Mg was used for this purpose. The casting is intended for the production of a wire connector for high voltage power transmission networks. Die casting method is used. The results obtained from the stimulation of pouring and crystallization of the casting are presented. Based on the located defects and the analysis performed, changes of the technology were made, which ultimately ensure the formation of a defect-free and soundness casting.

The article deals with the optimization of vertical surfaces with continuous and discrete finning under conditions of natural convection. The optimization was carried out using experimental data obtained for finned surfaces made of steel, taking into account the non-isothermal temperature distribution over the surface of continuous and discrete fins. The dependences of the optimal distance between the ribs on the Rayleigh number and the geometric dimensions of the ribs are found. It was found that with a decrease in the Rayleigh number for discrete non-isothermal fins, the optimal distance between the fins increases compared to the same distance for continuous non-isothermal fins. The differences can be more than 30%. The obtained results for continuous non-isothermal fins are compared with the known results for isothermal fins. It is shown that the presence of non-isothermicity on the surface of continuous fins made of metal materials leads to the need to reduce the inter-fin distance by up to 40%. The results obtained can be useful in the design of finned surfaces under natural convection conditions.

The paper studies the process of restoration of worn-out parts of agricultural machinery under submerged arc welding, produces definable and determining similarity criteria characterizing the process and discloses their physical entity. The methodology is developed and the criterion equation is received for determining and optimizing the hardness of metal coatings obtained, which is a scientific basis for conducting targeted experiments. An outfit is made for surfacing ploughshares submerged, that allows changing the basic factors without stepwise method. Experimental studies are conducted, as a result of which an analytic form of criteria equation is produced and optimum modes of the recovery of details under gumboil arc welding are established mined in Georgia.

The set of methods and rules in the process of providing raw materials can be considered a strategy for stock management. Each strategy is associated with specific and expected costs. Still, optimally, we can call that strategy that, under the given conditions, leads to minimal expenses related to the material provision of the studied system. Part of the stock management process is establishing the timing of the deliveries, the necessary volumes and the distribution of the incoming lots to the various warehouses and units. The search for optimal strategies is subject to the theory of optimal stock management. This makes it possible to release significant funds frozen in the form of stocks, which leads to increased efficiency of the material resources used. The optimal inventory management strategy and flexibility also lead to improved production processes and reduced and excluded possible interruptions caused by lack or shortage of materials. The stock management process influences the planning, forecasting, and fulfilment of production needs and orders.
The elements of the business system described so far, in which raw materials, materials and their stocks have a significant impact, show the importance of the stock management strategy of each economic unit. That the chosen and functioning system is optimal is a substantial part of the overall success in any enterprise or other form of business process implementation.

The subject of the conducted research and development project was the simulation modeling of solutions for a mass production system of customized furniture. Within the project, a digital twin of the custom furniture production and flexible manufacturing in the FlexSim 3D Simulation Software environment were utilized. The research and development work aimed to investigate the impact of production volume on machine load and the overall system efficiency. The scientific paper presents the methodology of project implementation, as well as the characteristics of input data and the process of producing customized furniture. The functioning logic of the simulation model is also described, along with the outcomes of the solutions for various scenarios. The paper includes the results of computer simulations for individual variants and provides potential recommendations. The project was carried out at Handcraft Sp. z o.o. company.

As plastic products shrink during cooling, so knowledge of shrinkage factor for different materials is required. The main objective of the study is to examine the influence of mold cooling process on subsequent deformation of finished part. To achieve the goal, simulations were carried out at different temperatures of the cooling agent. Statistical processing was performed and a regression model was derived describing the relationship between temperature, time and deformation during cooling.