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Influence of the annealing condictions on the chemical structure of LaBaGdCo ceramics
Open Research DataCeramic samples based on Barium, Lanthanum, Gadolinium and Cobaltium were produced by solid state reaction. After sintring in a furnance, samples were annealed at 300 Celsius degree in wet and dry atmosphere. Annealing takes 72h or 2h. Results of annealing were observed by X-Ray photoemission spectroscopy (XPS), OmicronNanotechnology. XPS analysis...
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Implementation of spatial/polarization diversity for improved-performance circularly polarized multiple-input-multiple-output ultra-wideband antenna
PublicationIn this paper, spatial and polarization diversities are simultaneously implemented in an ultra-wideband (UWB) multiple-input-multiple-output (MIMO) antenna to reduce the correlation between the parallel-placed radiators. The keystone of the antenna is systematically modified coplanar ground planes that enable excitation of circular polarization (CP). To realize one sense of circular polarization as well as ultra-wideband operation,...
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Assessment of diversity and composition of bacterial community in Sludge Treatment Reed Bed systems
PublicationDue to their low emission of odours and lack of the need to apply additional chemical agents, sludge treatment reed beds (STRBs) constitute an economically feasible and eco-friendly approach to sewage sludge management. Correctly designed and operated STRBs ensure effective reduction of the dry matter content coupled with the mineralisation of organic compounds. Successful operation of STRBs relies on complex interactions between...
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Antenna Optimization Using Machine Learning with Reduced-Dimensionality Surrogates
PublicationIn modern times, antenna design has become more demanding than ever. The escalating requirements for performance and functionality drive the development of intricately structured antennas, where parameters must be meticulously adjusted to achieve peak performance. Often, global adjustments to geometry are necessary for optimal results. However, direct manipulation of antenna responses evaluated with full-wave electromagnetic (EM)...
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Improved energy management technique in pipe-embedded wall heating/cooling system in residential buildings
PublicationEffective and environmentally responsive techniques of energy management in residential buildings are desirable for the resulting reduction of energy costs and consumption. In this paper, an improved and efficient technique of energy management in pipe-embedded wall heating/cooling systems, called the Thermal Barrier, is described. Specifically, the Thermal Barrier is a technique focused on the management and control of heat...
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Improved energy management technique in pipe-embedded wall heating/cooling system in residential buildings
PublicationEffective and environmentally responsive techniques of energy management in residential buildings are desirable for the resulting reduction of energy costs and consumption. In this paper, an improved and efficient technique of energy management in pipe-embedded wall heating/cooling systems, called the Thermal Barrier, is described. Specifically, the Thermal Barrier is a technique focused on the management and control of heat supply...
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Evaluation of VSC Impact on Power System Using Adequate P-Q Capability Curve
PublicationRenewable energy sources, which are becoming increasingly popular, often use a voltage source converter (VSC) for connection to the power system. Assessing the effects of connecting such a source to the power system is essential to ensure the proper operation of the power system and the connected source. For this purpose, it is necessary to know the range of active and reactive power generation by the converter. The authors indicate...
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Methods for physical impairment constrained routing with selected protection in all-optical networks
PublicationIn this paper, we investigate the problem of survivable all-optical routing in WDM networks with physical impairments. One of the recent key issues in survivable optical network design refers to maximization of the ratio of routeable demands while keeping the overall network cost low. In WDM networks, this goal can be achieved by routing as many demands in all-optical way as possible. Based on the latest technical trends driven...
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A New Method of the Load Compensation Use During Creation of Post Blackout Start-up Path in Power System
PublicationIn the paper a new method of effective use of load compensation during creation of post blackout start-up path is proposed. Theoretical assumptions and simulation results of an investigation are presented. An experiment performed in the Polish Power System is also described. This experiment proved that the method proposed by the authors is advisable. The method may be utilized by power system operators for power system restoration...
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A Novel Multicast Architecture of Programmable Networks
PublicationIn the paper a multicast architecture for programmable networks based on separation of group management and network control tasks is proposed. Thanks to this separation, services which want to make use of multicast communications no longer have to implement low-level network functionalities and their operation is greatly simplified. Abstracting service’s view of the network into a fully connected cloud enables us to transparently...
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Reliable underwater communication system for shallow coastal waters
PublicationThis paper presents a reliable and robust low data rate spread spectrum approach which is implemented in the acoustic underwater communication system for shallow coastal waters. It shows operation assumptions of spread spectrum techniques based on the wellknown Shannon equation. It describes two methods of spread spectrum: frequency hopping spread spectrum and direct sequence spread spectrum; their block diagram and their characteristics...
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CMOS implementation of an analogue median filter for image processing in real time
PublicationAn analogue median filter, realised in a 0.35 μm CMOS technology, is presented in this paper. The key advantages of the filter are: high speed of image processing (50 frames per second), low-power operation (below 1.25 mW under 3.3 V supply) and relatively high accuracy of signal processing. The presented filter is a part of an integrated circuit for image processing (a vision chip), containing: a photo-sensor matrix, a set of...
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Transient States during Short-circuit in a Line Powered by UPS and its Impact on Earth Fault Loop Impedance Measurement and Power Quality
PublicationThe short-circuit in a line powered by Uninterruptible Power Supply (UPS) during different UPS operation modes is presented in the article. The transient state condition related to the short-circuit in a line fed from double conversion On-line UPS is discussed in detail. The results of the measurements of earth fault loop impedance (FLI) in circuits powered by UPS with the instruments of various manufacturers are presented. The...
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Implementation of DEIS for reliable fault monitoring and detection in PEMFC single cells and stacks
PublicationDynamic Electrochemical Impedance Spectroscopy (DEIS) was presented as novel method for diagnostic and monitoring of PEMFC stack and single cells operation. Impedance characteristics were obtained simultaneously with current - voltage characteristics for stack and each individual cell. Impedance measurements were performed in galvanodynamic mode. It allowed to compare performance of each cell and identification of faulty cell operation...
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Importance of artificial intelligence to support the process of anaerobicdigestion of kitchen waste with bioplastics / Znaczenie sztucznej inteligencji we wspomaganiu procesu beztlenowej fermentacji odpadów kuchennych zawierających bioplastiki
PublicationArtificial intelligence (AI) and machine learning were used to obtain more effective methods for conducting the digestion process and achieving final products. Data acquisition was carried out by an automatic monitoring and anal. research. The knowledge describing the anaerobic digestion process was summarized in the form of rules: IF (premise) THEN (conclusion). The compiled set of rules created a knowledge base of the expert...
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Experimental certification of an informationally complete quantum measurement in a device-independent protocol
PublicationMinimal informationally complete positive operator-valued measures (MIC-POVMs) are special kinds of measurement in quantum theory in which the statistics of their d2-outcomes are enough to reconstruct any d-dimensional quantum state. For this reason, MIC-POVMs are referred to as standard measurements for quantum information.Here, we report an experiment with entangled photon pairs that certifies, for what we believe is the first...
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Functional safety analysis including human factors
PublicationThe article addresses selected aspects of human factors that should be taken into account during the design of safety-related functions for a complex hazardous installation and its protections. In such installations the layer of protection analysis (LOPA) methodology is often used for simplified risk analysis based on defined accident scenarios. To control the risk the safety instrumented functions (SIFs) are identified and their...
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Pumps, Turbines and Small Hydropower, LEC/LAB, DaPE, sem.5 winter 2022/23 (M:320403W0)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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Pumps, Turbines and Small Hydropower, LEC/LAB, ET, sem.7 winter 2022/23 (PG_00042108)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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Pumps, Turbines and Small Hydropower, LEC/LAB, DaPE, sem.5 winter 2023/24 (M:320403W0)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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Pumps, Turbines and Small Hydropower, LEC/LAB, ET, sem.7 winter 2023/24 (PG_00042108)
e-Learning CoursesThe aim of the course is to identify and demonstrate knowledge of the major concepts, theoretical perspectives, and historical trends in small hydropower. This course examines the principles of sustainability and renewable energy conversion with emphasis on hydro energy resources. Concentration is placed on the relationships between the renewable resources, conversion technology and economic feasibility along with consideration...
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COMPARATIVE ANALYSIS OF RESULTS OF APPLICATION OF MARKOV AND SEMI-MARKOV PROCESSES TO RELIABILITY MODELS OF MULTI-STATE TECHNICAL OBJECTS
PublicationDuring rational operation of technical objects and systems various operational decisions are made and decision-making process itself should be consisted in selecting that considered most favourable out of all possible to be taken. Choice of such decision is possible after taking into account many different information items but it never be completely correct without accounting for data and indices dealing with reliability. In...
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Thermal failure of a second rotor stage in heavy duty gas turbine
PublicationThe impulse mode of operation and the supply of various types of fuels causes frequent failures even in the heavy duty gas turbines. The paper presents the ravages of second rotor stage failure in a gas turbine. The excessive thermal elongation rise caused by fuel change was indicated as the main cause. We applied nonlinear numerical analysis, preceded by thermodynamic calculations of the turbine and visual inspection of the effects...
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Chip suction system in circular sawing machine: empirical research and computational fluid dynamics numerical simulations
PublicationThe experimental analysis of the wood chip removing system during its redesigning in the existing sliding table circular saw and computational fluid dynamic (CFD) numerical simulations of the air flow process is presented in the paper. The attention was focused on the extraction hood and the bottom shelter of the actual existing system. The main aim was to perform experimental research on the pressure distribution inside the...
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Visualisation forms in passive sonar with towed array
PublicationArtykuł dotyczy organizacji zobrazowań na monitorach modernizowanego w KSEM sonaru pasywnego z długą, holowaną za rufą okrętu, anteną akustyczną. We wprowadzeniu opisano strukturę takiego sonaru oraz sposób pozyskiwania i charakter odbieranych sygnałów jako podstawę organizowania zobrazowań efektów nasłuchu. Dalej opisano inne czynniki wpływające na organizację obrazów na monitorach sonaru tzn. zadania operatorów, organizację i...
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INVESTIGATION OF JOURNAL SLIDE BEARINGS UNDER THE ANGLE OF THEIR FUNCTIONING
PublicationPaper presents the structure and principle of operation of a stand for measurements of influence of the lubrication method and process on functioning of journal slide bearings in their various technical states. Measurements performed on the stand make it possible to take advantage of the new method of evaluating the influence of physical and chemical properties of lubricating oil on the coefficient of friction in the mixed friction...
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International architectural - urban - landscape design workshops to strengthen students’ education, capabilities and mobility
PublicationFive international architectural/urban/landscape workshops in Poland and Portugal between 2011 and 2015 are discussed in this article. The general aims of the workshops were to plan to connect divided city spaces, to harmonise them and make them attractive for different uses. The main task was to create in multicultural groups of students the vision of sustainable development in the context of architecture, urban and landscape...
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Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines. Part II. Unsteady processes
PublicationThe second part of the article presents the results of operating diagnostic tests of a two- and three-shaft engine with a separate power turbine during the start-up and acceleration of the rotor units. Attention was paid to key importance of the correctness of operation of the automatic engine load control system, the input for which, among other signals, is the rate of increase of the exhaust gas flow temperature. The article...
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Automatic road traffic safety management system in urban areas
PublicationTraffic incidents and accidents contribute to decreasing levels of transport system reliability and safety. Traffic management and emergency systems on the road, using, among others, automatic detection, video surveillance, communication technologies and institutional solutions improve the organization of the work of various departments involved in traffic and safety management. Automation of incident management helps to reduce...
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Practical Trial for Low-Energy Effective Jamming on Private Networks With 5G-NR and NB-IoT Radio Interfaces
PublicationFourth-generation (4G) mobile networks are successively replaced by fifth-generation (5G) ones, based on the new releases of the 3rd Generation Partnership Project (3GPP) standard. 5G generation is dedicated to civilian users and the conducted analytical work shows that it has numerous technological gaps that prevent its direct implementation in military communications systems. However, the recent armed world conflicts showed that...
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Enhancing rheological muscle models with stochastic processes
PublicationPurpose: Biological musculoskeletal systems operate under variable conditions. Muscle stiffness, activation signals, and loads change during each movement. The presence of noise and different harmonic components in force production significantly influences the behaviour of the muscular system. Therefore, it is essential to consider these factors in numerical simulations. Methods: This study aims to develop a rheological mathematical...
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Domestic Wastewater Treatment
PublicationSSF systems are usually applied at the 2nd stage of domestic wastewater treatment, after mechanical treatment. The number of such installations working at the moment in Europe is estimated to be 100,000. In Germany about 10,000 systems are in operation.
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Application of Mazur-Orlicz`s theorem in AMISE calculation
PublicationW pracy podano nowe wyprowadzenie formuły asymptotycznej błędu aproksymacji dla operatorów całkowych w przestrzeniach niezmienniczych na przesunięcia. Obliczono asymptotykę błędu średniokwakratowego dla estymatora gęstości.
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Wybrane metody diagnostyki łożysk silników indukcyjnych oparte o pomiar prądu
PublicationW artykule zawarto przegląd wybranych metod diagnostyki łożysk silnika indukcyjnego, bazujących na pomiarach prądu zasilającego. Jedno z nowych rozwiązań przetwarzania sygnałów zostało zaadaptowane przez autorów do stosowanego przez nich systemu diagnostycznego. Wyniki wstępnych badań symulacyjnych zweryfikowanych badaniami na rzeczywistym obiekcie wskazują, że rozwiązanie to ułatwia diagnozowanie. Autorzy zamierzają prowadzić...
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Założenia funkcjonalne i koncepcja systemu wywołania w niebezpieczeństwie w morskiej strefie przybrzeżnej
PublicationW pracy opisano problem wywołania w niebezpieczeństwie w morskiej strefie przybrzeżnej A1. Opisano aktualny sposób realizowania takich wywołań, opisano koncepcję nowego systemu wywołania opartego o infrastrukturę telekomunikacyjną operatora sieci telefonii komórkowej GSM, przeznaczonego dla potrzeb coraz liczniejszych użytkowników nieinstytucjonalnych. Na podstawie wykonanych analiz scharakteryzowano zagadnienie wyznaczania pozycji...
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Indicators describing the effectiveness of tax systems of selected OECD countries
Open Research DataThe following research data include indicators describing the effectiveness of the tax administration activity in Poland compared to selected countries. In economic understanding efficiency is measured by the calculation of the expenditure of funds spent on its operation and performance of statutory functions. In this respect, the basic indicator is...
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Strucutral steel - tensile test results
Open Research DataModern floating structures such as ships, oil platforms and offshore wind towers are built mostly of structural steel. It is a material that is subject to requirements which, when met, allows the construction and safe operation of the structure throughout its entire work cycle. One of the basic criteria that a material must meet is its strength. The...
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Valence state of Manganium in a MnCoO ceramics
Open Research DataManganium -cobalt based ceramics materials were produced by solid state reaction and sintred in a furnance in air atmosphere for 20h. Annealing temperature was 600 Celsius degree. For investigations a series of samples, with a various composition was chosen: MnCoO, Mn, Co2O and Mn2CoO. In order to determine valence states of the Mn, X-Ray photoemission...
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Lanthanum investigations in ceramics annealed in a dry and wet atmosphere
Open Research DataCeramics based on Barium, Lanthanum, Gadolinium and Cobaltium were produced by standard solid state reaction from oxides and carbonate powders. After sintring, samples were annealed for 2 hours or 72 hours at 300 Celsius degree in a both: wet and dry atmosphere. Results of annealing on a chemical composition and valence state of lanthanum were observed...
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Investigations of the valence state of Co in a MnCoO ceramics
Open Research DataMcCoO ceramics materials were produced by solid state reaction and sintred in a furnance in air atmosphere for 20h. Annealing temperature was 600 Celsius degree. For investigations a series of samples, with a various composition was chosen: MnCoO, Mn, Co2O and Mn2CoO. Chemical behaviour of the Cobaltium was measured by XPS method. The analyses were...
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Measurements of the chemical composition of LTO:Cu powders
Open Research DataLithium titanate doped by copper was measured by X-ray photoemission spectroscopy (XPS). For sol-gel synthesis lithium acetate dehydrate and titanium (IV) butoxide 97% and copper (II) nitrate from Alfa Aesar were used as a reagents. Cu precursor was added in the proper weight to get an x index equal 0, 0.1 and 0.2. In the first step lithium acetate...
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The influence of SVC on the progress of voltage collapse
PublicationThe article presents the simulation concerning the cooperation of SVC circuit with a generative set in time, when of power system reaches low values which may lead to the fall-out of generator from the synchronous operation.
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Application of Pierson-Moskowitz wave spectrum to solution differential equations of multihull vessel
PublicationMotion of a dynamic system can be generated by different external or internal factors. At mathematical modelling external excitation factors of the most significant effect on the system, are selected. Such external factors are usually called excitations. Response of the system to given excitations is mathematically characterized by a definite transformation called operator of a system. For a broad class of dynamic systems the...
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Device for spoofing in global positioning system
PublicationThis article describes the device which may be used to generate false GPS signals and emit them into radio communication channel. Such attack is called GPS spoofing. Each GPS receiver which remains in the range of a spoofing device (called spoofer) indicates time and position coordinates which are predetermined by the spoofer’s operator. Spoofing may be used e.g. in order to disable the terrorist group from obtaining correct navigation...
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Global Optimization for Recovery of Clipped Signals Corrupted With Poisson-Gaussian Noise
PublicationWe study a variational formulation for reconstructing nonlinearly distorted signals corrupted with a Poisson-Gaussian noise. In this situation, the data fidelity term consists of a sum of a weighted least squares term and a logarithmic one. Both of them are precomposed by a nonlinearity, modelling a clipping effect, which is assumed to be rational. A regularization term, being a piecewise rational approximation of the ℓ0 function...
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In Situ Verification of Numerical Model of Water Hammer in Slurries
PublicationThis paper presents a numerical model of transient flow in a pressure slurry pipeline network with verification based on in situ measurements. The model, primarily verified in laboratory conditions, has been extended and applied to the case of a large and complex slurry pipeline network in Poland. In the model, the equivalent density concept was applied. In situ experiments were performed for various unsteady flow episodes, caused by...
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Energy Systems Stations, W, ET, sem.7, zimowy 22/23 (PG_00042106)
e-Learning CoursesInternal combustion engines - principle of operation and classification. Heat balance of the engine. Uniform and combined propulsion systems.The main comonents of the propulsion system. Power plant efficiency and waste heat utilization. Cooling water system, lubricating oil system, fuel oil systeml, gaseos fuel system (LNG), compressed air system, exhaust gas system. Fittings and accessories of pipeline systems in the power plant....
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The voltage on bus bars of the main switchboard of the ferry electrical power system during a sea voyage
Open Research DataThe dataset is part of the research results on the quality of supply voltage on bus bars of the main switchboard of the ship's electrical power system in different states of ship exploitation. The attached dataset contains the measurement results carried out onboard the ferry during a sea voyage.
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Voltage fluctuations on the main switchgear of the industrial power system supplying the rolling mill motors_part_2
Open Research DataThe dataset presents the voltage waveforms on the bus bars of the main switchgear of the industrial power network for the supply of rolling mills. The data was recorded during an experiment whose purpose was to determine a level of short-term and long-term flicker caused by voltage fluctuations. In the virtual application of flickermeter, a hardware...
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Water-lubricated stern tube bearing - experimental and theoretical investigations of thermal effects
PublicationThe paper presents research results of thermal phenomena accompanying operation of a water-lubricated stern tube bearing with axial grooves. Experimental tests revealed, that intensity of forced axial flow has strong influence on bush temperature. Numerical simulations focused on investigation of the thermal phenomena under operation of water-lubricated journal bearing showed, that restricted axial flow promotes backflow of the...