The article presents the features of mathematical modeling of the heat release during the hardening of composite cellular materials using the example of non-autoclaved foam concrete. The reactions of hardening and structure formation in foam concrete are exothermic and are called hydration reactions. The article lists the technological factors affecting the heat release during hydration. The basis for r (…)
Several methods of production of castings have been studied via the example of a case part, an axial piston pump back-end cover, namely. These methods include sand mold casting, casting into molds made of cold-hardening mixtures, permanent mold casting, lost-wax casting, lost-foam casting. We have considered only those casting methods, which ensure obtaining internal cavities with curved axes without th (…)
In this article, based on the forecast of the state dynamics of control systems with the use of cellular automata, we consider the obtained results that provide the theoretical basis for the development of a conceptual model of forming a reserve of fire monitoring tools. The article identifies analytical dependences of the assessment of the limit states of the monitoring system for solving the challenge (…)
Drilling with a rotary steerable system (RSS), the mechanical drilling speed increases by two times compared to drilling with a screw bottom-hole motor, which provides significant savings drilling-time. The effective length of the horizontal elbow increases, which enables to increase the production rate more than twice. It is found that in comparison with the bottom hole motor, RSS provides drilling smo (…)
Automated technological devices need diagnostics. At present, it is possible and necessary to use a wide range of sensors, computing systems and artificial intelligence methods based on neural networks, fuzzy inference systems in diagnostic systems. This paper proposes three models of information processes for diagnosing mechatronic systems - parallel, sequential and combined. To diagnose the nodes of m (…)
Blade load analysis of the turbine blades is generally very crucial for hydraulic machine designs, especially in a case of axial turbines, where the shroud is missing. The torque in this case is transmitted only by the blade pivots or fixed support to hub. Blade loading can be especially significant for off-design operating regimes. Modulation of the excitation frequencies and pressure pulsations is ena (…)
Noise belongs among the negative phenomena in our environment and can have a negative effect on human health. Excessive noise occurs in many areas, e.g. in transport, aeronautics, and during manufacturing processes. It is often necessary to meet specified noise limits. Acoustic measurements are carried out in many cases, e.g. in order to evaluate the sound absorption properties of investigated materials (…)
The paper deals with the evaluation of mechanical properties of a biopolymer composite, where a low-temperature plasma, atmospheric dielectric barrier discharge (DBD) physical treatment was used to improve adhesion at the interface between the polymer and natural fibers. The polymer composite matrix was PLA polymer from NatureWorks LLC. The reinforcing filler were natural coconut fibers, which were in t (…)
With the rise of modern technology in computer science and engineering, as well as with the growing population in big cities around the world, many new approaches for person detection have become a very interesting and demanding topic. Person detection is a necessary building block for people monitoring systems and, therefore, various detection methods must be inspected comprehensively in order to selec (…)
Nowadays, recycling is a very often discussed topic though its realization varies. One way the recycled material has to be collected, subsequently sorted, melted, cast repeatedly and the casting has to be respectively machined. Otherwise given casting can be recycled by repair in a form of material adding. This way of repair is suitable, especially where the product of the casting is degraded due to mat (…)
The article discusses a new breakthrough methodology for forecasting events and phenomena that are diverse in their physical nature. The article uses the total electron content trends (TEC) of the ionosphere as initial data for earthquake forecasting. The total electron content of the Earth’s ionosphere is a good indicator of its state and its dynamics. It has been found that the most effective fo (…)
A shape optimization problem is increasingly popular in various parts of industry and academia. Several shape optimization approaches emerged in the past few years. Population-based methods (PPM) are among them, with convenient attributes and characteristics that lead to a discovery of proper solutions of investigated problems. Crucial quality of PPM lies primarily in number of randomly scattered indivi (…)
The article presents the results of a numerical analysis of the flow conditions in the air distribution element in a combined refrigerator and freezer. A numerical analysis was carried out using the boundary conditions identified through an experiment. The article includes an analysis of the impact of the mesh type and the used turbulence models on the profile of the air flow velocity in the outlet open (…)
The paper deals with the design of an automated measuring and error detection system integrated into the turning machine. The experimental measuring device is based on a laser sensor with data transfer to the PLC control system. The main advantage of the designed experimental system is the possibility of measuring during the whole production process. The start position for the next product turn is index (…)
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