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Institute of Naval Architecture
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Year 2021
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MODERNIZACJA DYDAKTYCZNEGO STANOWISKA LABORATORYJNEGO UMOŻLIWIAJĄCEGO ANALIZĘ PORÓWNAWCZĄ SPRAWNOŚCI ŚRUB NAPĘDOWYCH JACHTU MOTOROWEGO
PublicationW artykule przedstawiono autorską metodę wyznaczania sprawności działania różnych śrub napędowych jachtu motorowego na podstawie wyników badań wykonanych na zmodernizowanym stanowisku laboratoryjnym. Modernizacja stanowiska składającego się ze źródła mocy w postaci silnika elektrycznego, części pośredniczącej i pędnika polegała na dodaniu przetwornika częstotliwości umożliwiającego starowanie silnikiem elektrycznym, czujnika do...
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Monitoring Regenerative Heat Exchanger in Steam Power Plant by Making Use of the Recurrent Neural Network
PublicationArtificial Intelligence algorithms are being increasingly used in industrial applications. Their important function is to support operation of diagnostic systems. This paper pesents a new approach to the monitoring of a regenerative heat exchanger in a steam power plant, which is based on a specific use of the Recurrent Neural Network (RNN). The proposed approach was tested using real data. This approach can be easily adapted to...
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NEW DESIGNS OF MAGNETIC FLUID SEALS FOR RECIPROCATING MOTION
PublicationT he operating conditions of magnetic fluid seals during reciprocating motion are so different from those observed in rotating motion that the use of their conventional structures for reciprocating motion seals yields no good results. The analysis of the sealing mechanism of magnetic fluid seals in reciprocating motion shows that the operation of these seals is affected by the carry-over phenomenon and magnetic fluid...
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Novel Cold Crucible Ultrasonic Atomization Powder Production Method for 3D Printing
Publication: A new powder production method has been developed to speed up the search for novel alloys for additive manufacturing. The technique involves an ultrasonically agitated cold crucible installed at the top of a 20 kHz ultrasonic sonotrode. The material is melted with an electric arc and undergoes pulverization with standing wave vibrations. Several different alloys in various forms, including noble and metallic glass alloys, were...
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Numerical and experimental study on effect of boundary conditions during testing of stiffened plates subjected to compressive loads
PublicationThis study analyses the effect of boundary conditions during testing on the structural behaviour stiffened plates with different thicknesses subjected to compressive loads. The goal of the compressive tests is to analyse the ultimate strength of a stiffened plate. During the test, relevant physical quantities are measured and investigated. The supporting structure's behaviour is investigated by analysing the force-displacements...
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Numerical modelling of the mesofracture process of sintered 316L steel under tension using microtomography
PublicationThis paper concerns numerical modelling of the deformation process, taking into account the local fracture of porous 316L sinters at the mesoscopic scale using the finite element method. Calculations are performed with the use of geometrical models, to map the realistic shape of the porous mesostructure of the material, obtained by means of computed microtomography. The microtomographic device has limited and insufficient measurement...
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PARAMETRIC ANALYSIS OF THE EFFICIENCY OF THE COMBINED GAS-STEAM TURBINE UNIT OF A HYBRID CYCLE FOR THE FPSO VESSEL
PublicationA thermal diagram of the combined gas‒steam turbine unit of a hybrid cycle, which is an energy complex consisting of a base gas turbine engine with a steam turbine heat recovery circuit and a steam-injected gas turbine operating with overexpansion, is proposed. A mathematical model of a power plant has been developed, taking into consideration the features of thermodynamic processes of simple, binary, and steam-injected...
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Performance and Emission Modelling and Simulation of Marine Diesel Engines using Publicly Available Engine Data
PublicationTo analyse the behaviour of marine diesel engines in unsteady states for different purposes, for example to determine the fuel consumption or emissions level, to adjust the control strategy, to manage the maintenance, etc., a goal-based mathematical model that can be easily implemented for simulation is necessary. Such a model usually requires a wide range of operating data, measured on a test stand. This is a time-consuming process...
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Photogrammetry image-based approach for imperfect structure modelling and FE analysis
PublicationThis study aims to model and analyse imperfect tructures using real measurements, employing photogrammetry technique commonly used in the geodesy. The study highlights the capability of the photogrammetry in aiding the structural analysis of imperfect engineering objects. Firstly, the photogrammetry measurements of a stiffened plate are carried out using a specially designed for the purpose experimental stand. Then, the plate surface...
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PROJEKT STANOWISKA DYDAKTYCZNEGO DO WYZNACZANIA CHARAKTERYSTYK POMP WIROWYCH
PublicationW artykule przedstawiono projekt oraz gotowe stanowisko do wyznaczenia charakterystyk przepływowych pomp wirowych w pracy indywidualnej oraz w wybranych wariantach współpracy szeregowej jak i równoległej. Obserwację parametrów kontrolnych pomp wirowych w różnych stanach pracy: dławienie przepływu, zmiana prędkości obrotowej. Dużą zaletą stanowiska jest wymuszanie obserwację zjawiska kawitacji.
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Robust-adaptive dynamic programming-based time-delay control of autonomous ships under stochastic disturbances using an actor-critic learning algorithm
PublicationThis paper proposes a hybrid robust-adaptive learning-based control scheme based on Approximate Dynamic Programming (ADP) for the tracking control of autonomous ship maneuvering. We adopt a Time-Delay Control (TDC) approach, which is known as a simple, practical, model free and roughly robust strategy, combined with an Actor-Critic Approximate Dynamic Programming (ACADP) algorithm as an adaptive part in the proposed hybrid control...
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Simplified approach to assess the dynamic response of a container ship subjected to bow slamming load
PublicationSimplified approach to assess the dynamic response of a container ship subjected to the bow slamming load, resulting in a transient vibratory response, typically called a 'whip-ping', is presented. The accurate numerical modelling is very complex and involves cou-pling of the hydrodynamic and structural solution at every time step, leading to huge com-putational and workload cost. Thus, the one-way coupling methodology is adopted,...
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TEST METHOD FOR DETERMINING THE CHEMICAL EMISSIONS OF A MARINE DIESEL ENGINE EXHAUST IN OPERATION
PublicationThe article briefly describes the problem of air pollution caused by sea-going ships and the resulting restrictions on the emission of toxic and harmful chemical compounds in the exhaust of marine engines, introduced by the International Maritime Organization (IMO) under the International Convention for the Prevention of Sea Pollution from Ships (MARPOL 73/78). Such emissions provide a significant metrological problem, not only...
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The Development of a Combined Method to Quickly Assess Ship Speed and Fuel Consumption at Different Powertrain Load and Sea Conditions
PublicationDecision support systems (DSS) recently have been increasingly in use during ships operation. They require realistic input data regarding different aspects of navigation. To address the optimal weather routing of a ship, which is one of the most promising field of DSS application, it is necessary to accurately predict an actually attainable speed of a ship and corresponding fuel consumption at given loading conditions and predicted...
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The Matter of Decision-Making Control Over Operation Processes of Marine Power Plant Systems with the Use of their Models in the form of Semi-Markov Decision-Making Processes
PublicationThe article presents the possibility to control the real operation process of an arbitrary device installed in the marine power plant based on the four-state semi-Markov process, being the model of the process, which describes the transition process of operational states of the device and the transition process of its technical states. All these states are precisely defined for the ship main engine (SG). A hypothesis is proposed...
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Turning maneuver as a potential cause of the next stability failure mode for a ship in operation
PublicationThe only formal stability-related requirement referring to a turning maneuver of a ship results from the IS Codeand its application is limited to passenger ships only. The goal of the adopted criterion is to prevent an excessiveangle of heel in turn. Likewise, the remaining prescriptive criteria, this one is simply based on the concept ofa threshold that must not be exceeded. In this case, the angle of heel...
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Ultimate compressive strength assessment of uncleaned and cleaned corroded plates with locked crack
PublicationThe work presented here investigates the structural response of cleaned corroded plates, subjected to compressive load in the presence of a locked crack, where the change of mechanical properties as a result of corrosion development and the cleaning process is also accounted for. A Finite Element model for assessing the compressive strength, considering geometric and material nonlinearities, is developed, and the analysed plates...
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W-dominance: Tradeoff-inspired dominance relation for preference-based evolutionary multi-objective optimization
PublicationThe paper presents a method of incorporating decision maker preferences into multi-objective meta-heuristics. It is based on tradeoffcoefficients and extends their applicability from bi-objective to multi-objective. The method assumes that a decision maker specifies a priori each objective’s importance as a weight interval. Based on this, w-dominance relation is introduced, which extends Pareto dominance. By replacing reference...
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Wpływ parametrów zewnętrznych na wytwarzanie pary w kotle opalanym
PublicationW artykule przedstawiono analizę statystyczną wpływu parametrów zewnętrznych na strumień ciepła zawartego w paliwie dolotowym do okrętowego kotła opalanego. Jako parametry niezależne wytypowano średnią dobową moc chwilową silnika głównego i agregatów prądotwórczych, temperaturę wody zaburtowej oraz zanurzenie. Analizę przeprowadzono dla czterech różnych stanów eksploatacyjnych badanego statku.
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ZASTOSOWANIE STATYSTYKI F ROZKŁADU FISHERA-SNEDECORA DO OCENY ISTOTNOŚCI WPŁYWU ZMIAN STOPNIA KOMPRESJI SILNIKA O ZS NA ŚREDNIĄ WARTOŚĆ MIĘDZYSZCZYTOWĄ TEMPERATURY SPALIN WYLOTOWYCH
PublicationW artykule omówiono wpływ zmian stopnia kompresji na parametry pracy silnika o ZS, m.in. na temperaturę spalin wylotowych. Przedstawiono budowę stanowiska laboratoryjnego, na którym przeprowadzono badania eksperymentalne. Scharakteryzowano, w jaki sposób w istniejącym silniku wprowadzano faktyczne zmiany stopnia kompresji. Zaprezentowano program badań eksperymentalnych uwzględniający dostępne stanowisko badawcze i jego możliwości...
Year 2020
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Experimental Research on Insufficient Water Lubrication of Marine Stern Tube Journal Bearing with Elastic Polymer Bush
PublicationWater-lubricated bearings with polymer bushes are steadily gaining popularity due to their advantages, including environmental friendliness, relatively simple construction and long-term operation. Nevertheless, in practice instances of damage to such bearings occur due to insufficient or absent flow of the lubricating agent. In this study, experimental tests established that elastic polymer bush bearing is capable of operating...
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In vivo performance of intraperitoneal onlay mesh after ventral hernia repair
PublicationBackground: Ventral hernia repair needs to be improved since recurrence, postoperative pain and other complications are still reported in many patients. The behavior of implants in vivo is not sufficiently understood to design a surgical mesh mechanically compatible with the human abdominal wall. Methods: This analysis was based on radiological pictures of patients who underwent laparoscopic ventral hernia repair. The pictures...
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PORÓWNANIE SPRAWNOŚCI ŚRUB NAPĘDOWYCH JACHTU MOTOROWEGO NA STANOWISKU DYDAKTYCZNYM
Publicationw artykule przedstawiono autorską metodę wyznaczania sprawności działania różnych śrub napędowych jachtu motorowego na podstawie wyników badań wykonanych na stanowisku laboratoryjnym. Zastosowanie takiej metody porównawczej wymagało zbudowania prostego w użytkowaniu stanowiska dydaktycznego odwzorowującego możliwe warunki działania układu napędowego jachtu motorowego, składającego się ze źródła mocy w postaci silnika elektrycznego,...
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Reliability of Corroded Stiffened Plate Subjected to Uniaxial Compressive Loading
PublicationThe work is focused on the reliability of corroded stiffened plates subjected to compressive uniaxial load based on the progressive collapse approach as stipulated by the Common Structural Rules for Bulk Carriers and Oil Tankers, employing the limit state design. Two different cases have been investigated. In the first model, the corrosion degradation led to uniform thickness loss, whereas the mechanical properties were unchanged,...
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Towards Improving Optimised Ship Weather Routing
PublicationThe aim of the paper is to outline a project focusing on the development of a new type of ship weather routing solution with improved uncertainty handling, through better estimation of ship performance and responses to sea conditions. Ensemble forecasting is considered to take into account the uncertainty levels that are typical of operations in a stochastic environment. Increased accuracy of weather prediction is achieved through...
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WYBRANE ASPEKTY ZMĘCZENIOWYCH USZKODZEŃ OKRĘTOWYCH WAŁÓW NAPĘDOWYCH
PublicationProblem zmęczeniowego pękania konstrukcji okrętowych w sposób istotny dla eksploatacji tychże obiektów ujawnił się na przełomie lat 70. i 80. ubiegłego stulecia. Ponieważ pęknięcia zmęczeniowe dotyczą głównie kadłubów statków i są szczególnie dotkliwe dla dużych jednostek (zbiornikowców, masowców i kontenerowców), dlatego też cała uwaga towarzystw klasyfikacyjnych i biur projektowych skupia się głównie na tym aspekcie uszkodzeń...
Year 2019
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Diagnostic Model of Crankshaft Seals
PublicationT he paper presents a research stand being a diagnostic model of radial lip seals used, among others, on crankshafts of piston combustion engines in order to identify the correctness of their operation. The possibility of determining the technical condition of lip seals on the basis of the proposed coefficient of correctness of operation has been described. T he basic features of seals influencing their correctness of...
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Stateczność i niezawodność pełnomorskich platform wiertniczych
PublicationW pracy przedstawiono wieloletnie doświadczenia Autora w zakresie wybranych aspektów numerycznej analizy pełnomorskich platform wiertniczych, w szczególności stacjonarnych platform stalowych poddanych działaniu fal wiatrowych i wiatru. W opisie zachowania się platform uwzględniono współoddziaływanie trzech ośrodków: materiału konstrukcji, morskich fal wiatrowych i podłoża gruntowego. Przyjęcie do opisu stochastycznych właściwości...
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Stateczność samopodnoszących pełnomorskich platform wiertniczych w fazie eksploatacji
PublicationWspółczynnik bezpieczeństwa platformy Petrobaltic na moment obrotowy (stateczność ogólna) oszacowany przy założeniu, że konstrukcja jest traktowana jako układ słupów połączonych sztywnym pokładem, z korekcją efektów drugiego rzędu. Przemieszczenie poziome pokładu platformy wyznaczone, stosując odpowiedni model MES. Siła krytyczna nogi obliczona przy założeniu jej utwierdzenia w dnie morza. Wpływ odchyłki od idealnej geometrii rur...
Year 2017
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Improvement of microstructure and mechanical properties of high dense sic ceramics manufactured by high-speed hot pressing
PublicationNon-oxide ceramics possess high physical-mechanical properties, corrosion and radiation resistance, which can be used as a protective materials for radioactive wastes disposal. The aim of the present study was the manufacturing of high density SiC ceramics with advanced physical and mechanical parameters. The high performance on the properties of produced ceramics was determined by the dense and monolithic structure. The densified...
Year 2016
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Cavitation erosion resistance of thick CrC coating deposition by the Arc-PVD method
PublicationThe paper investigates the durability of chromium carbide (CrC) coatings, with thicknesses up to 20 μm, applied using the Arc-PVD technique, against cavitation erosion. The study employs the rotating disk testing method to evaluate the performance of these coatings. Findings indicate that the carbon content within the Cr-C coatings significantly influences their resistance to cavitation erosion, with variations ranging from 2 to...
Year 2012
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Modeling of Accidental Bunker Oil Spills as a Result of Ship's Bunker Tanks Rupture - a Case Study
PublicationAIS (Automatic Identification System) data analysis is used to define ship domain for grounding scenarios. The domain has been divided into two areas as inner and outer domains. Inner domain has clear border, which is based on ship dynamic characteristics. Violation of inner domain makes the grounding accident unavoidable. Outer domain area is defined with AIS data analyzing. Outer domain shows the situation of own ship in compare...