The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The article presents an FEM model of the spindle system, in which angular contact ball bearings with active preload control are used. This model allowed determining the frequency and form of natural vibrations of the system. The model was prepared using the Abaqus programming environment. Various bearing preload states were adopted during the tests. It was shown that the spindle system is sensitive...
The following work describes the application of a mathematical model based on Markov chain theory (MM) to estimate the fiber composite strength parameters, taking into account the laminate forming aspects using the vacuum bag method. This provides, from a unified position, a tool for a coordinated description of static strength and fatigue life. It was shown that the MM model gives relatively good...
The recommended optimal twist angles were determined for particular sections of the prototype rotor blade dedicated to an unmanned helicopter. The main rotor blade was tested in the GUNT HM 170 tunnel for four different air flow velocities and variable angles of attack. The blade model was divided into sections, each of them was made in the 3D printing technology. For all the sections, the maximum...
The effect of mechanical properties on wear resistance of Si3 N4 – SiC composite materials with different portions of SiC strengthening phase was investigated. Properties of monolithic silicon nitride were compared to ceramic composites consisting of Si3 N4 matrix with 10 and 20 vol.% SiC. The SiC strengthening phase had a positive effect on the hardness of Si3 N4 – SiC ceramic composite materials...
The paper presents an innovative method of metal forming of hollow flanged elements. In this process, flanges are formed using a movable sleeve, which moves in the opposite direction to the punch. The movement of the sleeve causes a closed impression to open, due to which the flange is also formed in a semi-free impression. The tube billets were made of the 42CrMo4 grade steel deformed under the cold...
The paper presents the result of the research on the impact of the accelerated aging process on selected operational properties of polylactide films containing natural antioxidants in the form of coffee, cocoa or cinnamon extracts. The research was focused on mechanical properties important for the packaging industry from the point of view of the reliability of the obtained products, i.e. tensile...
The designing activity has to result in completely new autonomous units sections of complex manufacturing processes and their systems. The solutions must be related to a number of new issues, not only of a technical and technological nature. The solutions designed for new types of interactions between people and technology will be required, and so will be the necessary skills and knowledge. New legal,...
Designing individualized medical devices requires the collection of anthropometric data from the patient. This can be done by using the 3D scanning process. Despite many advantages, it has significant drawbacks, limiting the suitability of its use for many types of medical devices. This paper presents the design of measuring station that allows increasing the quality of the anthropometric data obtained...
This paper presents the selected issues regarding the design of a complex object of a turbine jet engine inlet duct model for the purposes of numerical analysis related to the phenomenon of inlet vortex formation. The authors described the process of discretisation in the matter in question and presented certain guidelines for preparing and conducting discretisation of the computational area. The...
This paper analyses the changes in the values of the damping coefficient of shock absorbers, depending on the size and distribution of loads in passenger vehicles. The tests were conducted in two stages. During the first stage, the influence of the size of a load in vehicles, and changes in the tyre pressure values on the damping coefficient of shock absorbers was defined. During the second stage,...
The purpose of this research was to specify the interrelationships of various scientific disciplines based on the official declarations of scientists. The most required scientific disciplines were identified for multidisciplinary research. Undirected graphs with the specified parameters were used for modelling of community structure. On the basis of an open database POLON, a graph was created for...
The construction and installation of high-power wind farms triggers a number of problems related to the compensation of HV cable lines exporting power from a wind farm, and to the choice of compensation devices. The article describes problems that occur when wind farms are connected to the power system with a 110 kV line, characterizes the devices determining the reactive power balance. Two reactive...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.