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In this article, an analytical solution to a hydraulic network with a wide range of pipe lengths (up to 10 km) is proposed. The Finite-Difference Time-Domain (FDTD) method was applied with the aim of creating a regulation model for controlling both the flow rate of water from one of the two sources and the discharge pressure in the system. The system inertia requires an understanding of boundary conditions in the operation of pipeline networks, which must be known in order to regulate the required parameters with only minor deviations. The proposed model was compared to experimental data, while the mean absolute deviations in the individual system branches ranged from 1 to 5.19%. The created regulation model was subsequently tested by applying linear, sine and stochastic changes in the output load, while the ability to control the discharge pressure and the selected water flow rate was analysed. The effect of coefficient ε, which multiplies the effect of the difference between the measured and the predicted value of the discharge pressure on the boundary conditions of the discharge pressure in the system, was analysed in this paper. With the use of the proposed unsteady simulation of the fluid flow in the hydraulic system arranged in parallel and in series, the maximum deviation of the regulated pressure was 1.2% and the maximum deviation of the regulated flow rate was 5.3%. [ABSTRACT FROM AUTHOR]

This paper deals with joining dissimilar materials using thermal drilling technology as well as the combination of thermal drilling and adhesive bonding. The base materials for the experimental work were deep-drawn low-carbon steel DC04, HSLA steel TL 1550-220 + Z, and structural aluminum alloy EN AW-6082 T6 (AlSi1MgMn). The geometry of the formed joints was tested metallographically as the load-bearing shear capacity under the tensile shear test of single-lapped joints and the resistance of the joints against corrosion-induced disbonding in a climate chamber. The energy dissipated by the joints up to fracture was calculated from the load–displacement curves. The hybrid joints were compared with the bonded joints with the same overlap area in terms of the load-bearing capacity and energy dissipated at joint failure. The hybrid joints formed by thermal drilling and adhesive bonding with a rubber-based adhesive confirmed the synergistic effect—the adhesive provides the high load-bearing capacity of the joint, and the bushing formed by thermal drilling increases the dissipated energy of the joint at failure. The exposure of the joints in the climatic chamber did not cause a relevant reduction in the characteristics of the joints. [ABSTRACT FROM AUTHOR]

When milling complex parts or curved surfaces, we encounter several problems that must be addressed in the production process. Various factors affect the quality and accuracy of production. The main objective of this paper was to analyse the size of the effective tool diameter when machining a shaped surface concerning the selected position, namely at the perpendicular position of the tool. At the same time, the distribution of the engagement area on the tool surface was evaluated by extracting the area content and volume data at the point of contact. This study highlights the importance of the choice of finishing strategy in a CAM system. The results showed that the tool engagement size corresponded to the extracted data describing the area and volume for each tool position with regards to the curvature of the surface. The negative deviations obtained by the scanning method were due to machining near the tool centre, which was affected by the changing effective tool diameter. [ABSTRACT FROM AUTHOR]

One of the basic trends in the automotive industry today is to achieve the most acceptable ratio between the total weight of the car to its overall performance and utility properties. Reducing the weight of cars is largely due to the use of new materials, where composite materials offer a wide space for their application. Composite materials have their specific properties which is very beneficial in reducing the total weight. Another advantages is strength, stiffness, low fiber density, the ability to form them into any shape based on the required applications. One of the challenges associated with the use of composite materials is the search for new technological possibilities of joining composite materials with metals. These include technologies as for example riveting, ultrasonic welding, but especially gluing. Bonding is currently one of the most preferred ways of joining composite materials. The paper deals with testing of technology of bonding composite materials with metals used in the manufacture of automobiles and a comparison of individual results obtained from the experiment. [ABSTRACT FROM AUTHOR]

Measuring of mechanical parts, especially car components is one of the main testing procedure; errors caused throughout measuring can negatively affect the production process and so increase the production costs; article is approaching chosen measuring examples and offer possible methods for elimination of measurement errors; article also describes possible inaccuracy of 3D measuring due wrong measuring method choosing. [ABSTRACT FROM AUTHOR]

The history of modern composites begins in the 20th century, when a number of new materials and technologies were invented. New materials are necessary for electrical engineering and computer industry, but their importance rapidly grows in mechanical engineering, especially in aerospace and automotive industry. Industrial demands force to rapidly innovate and bring new materials, with essentially improved properties. Submitted paper deals with the basic overview of manufacturing, processing and main features of the composite materials, based on carbon fibers and their application in the automotive industry. [ABSTRACT FROM AUTHOR]