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Wyświetlanie 1-12 z 12
Tytuł:
Research on intelligent diagnosis method for large-scale ship engine fault in non-deterministic environment
Autorzy:
Feng, D.
Li, Y.
Powiązania:
https://bibliotekanauki.pl/articles/258452.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
non-determinism
large-scale ship engine
fault intelligent diagnosis
Opis:
Aiming at the problem of inaccurate and time-consuming of the fault diagnosis method for large-scale ship engine, an intelligent diagnosis method for large-scale ship engine fault in non-deterministic environment based on neural network is proposed. First, the possible fault of the engine was analyzed, and the downtime fault of large-scale ship engine and the main fault mode were identified. On this basis, the fault diagnosis model for large-scale ship engine based on neural network is established, and the intelligent diagnosis of engine fault is completed. The experiment proved that the proposed method has high diagnostic accuracy, engine fault diagnosis takes only about 3s, with a higher use value.
Źródło:
Polish Maritime Research; 2017, S 3; 200-206
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Selected problems of experimental testing marine stern tube bearings
Autorzy:
Barszczewska, Agnieszka
Piątkowska, Ewa
Litwin, Wojciech
Powiązania:
https://bibliotekanauki.pl/articles/260219.pdf
Data publikacji:
2019
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
marine bearings
polymer journal bearings
tribology
real scale test
Opis:
This paper presents typical methods for conducting experimental tests on main shaft slide bearings. There are described their possible testing capabilities , advantages , drawbacks and limitations. Various testing methods were analyzed to find a solution able of providing a wide range of possible investigations at possibly acceptable limitations.
Źródło:
Polish Maritime Research; 2019, 2; 142-154
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Scale effects in cavitation experiments with marine propeller models
Autorzy:
Szantyr, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/260100.pdf
Data publikacji:
2006
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
śruby okrętowe
kawitacja
cavitation
marine propellers
model experiments
scale effect
Opis:
The paper presents an overview of specific scale effects encountered in the cavitation experiments with marine propeller models. These scale effects result from unavoidable dissimilarity between model and full scale flow phenomena. They may influence first of all inception of different forms of cavitation, but they also are visible in development and desinence of cavitation on propeller blades. These scale effects may be divided into five main categories, which are described in detail. The influence of these five categories of scale effects on the different aspects of cavitation performance of marine propellers is discussed.
Źródło:
Polish Maritime Research; 2006, 4; 3-10
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modelling of lake waves to simulate environmental disturbance to a scale ship model
Autorzy:
Rak, Andrzej
Miller, Anna
Powiązania:
https://bibliotekanauki.pl/articles/34614624.pdf
Data publikacji:
2023
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
wave modeling
environmental disturbances
scale ship model
ship motion simulation
Opis:
In the development of ship motion control systems, software simulations or scale model experiments in pools or open water are very often carried out in the verification and testing stages. This paper describes the process of building a software wave simulator based on data gathered on the Silm Lake near Iława, Poland, where scale ship models are used for research and training. The basis of the simulator structure is a set of shaping filters fed with Gaussian white noise. These filters are built in the form of transfer functions generating irregular wave signals for different input wind forces. To enable simulation of a wide range of wind speeds, nonlinear interpolation is used. The lake wave simulation method presented in this paper fills a gap in current research, and enables accurate modelling of characteristic environmental disturbances on a small lake for motion control experiments of scale model ships.
Źródło:
Polish Maritime Research; 2023, 3; 12-21
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Critical review of propeller performance scaling methods, based on model experiments and numerical calculations
Autorzy:
Bugalski, T.
Streckwall, H.
Szantyr, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/258844.pdf
Data publikacji:
2013
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
propeller scale effects
open water tests
computational fluid dynamics (CFD)
Opis:
The article presents the results of experimental and numerical investigation of propeller scale effects, undertaken in co-operation of the Hamburg Ship Model Basin (HSVA), Germany, and Ship Design and Research Centre (CTO SA), Poland. The objective of the investigation was to test the adequacy of the methods currently used to account for the propeller scale effect and to develop possible improvement of the methods. HSVA has conducted model experiments in the large cavitation tunnel together with panel method and CFD calculations. CTO SA has performed model experiments in the towing tank, together with lifting surface and CFD calculations. Both institutions have suggested different new approaches to the problem and different new procedures to account for the propeller scale effects. In the article the procedures are presented together with the description of the underlying experimental and theoretical research.
Źródło:
Polish Maritime Research; 2013, 4; 71-79
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Physical fields during construction and operation of wind farms by example of Polish maritime areas
Autorzy:
Otremba, Z.
Andrulewicz, E.
Powiązania:
https://bibliotekanauki.pl/articles/260016.pdf
Data publikacji:
2014
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
marine environment
wind farms
physical field
large scale constructions
marine spatial planning
Opis:
The article discusses an important issue of technical pressure exerted on the marine environment during construction and operation of maritime wind farms (MFW) on waters of the Polish Exclusive Economic Zone. A motivation for analysing this issue is the need for attracting attention to the aspect of physical field modification as the factor which links large scale technical activity at sea with the existence and functioning of the marine ecosystem, including further consequences to its economic benefits. Based on current knowledge and authors’ analyses, the scale of modifications (disturbances) of physical fields expected to take place during MFW construction and operation was assessed.
Źródło:
Polish Maritime Research; 2014, 4; 113-122
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analysis of model-scale open-water test uncertainty
Autorzy:
Król, Przemysław
Powiązania:
https://bibliotekanauki.pl/articles/32898216.pdf
Data publikacji:
2022
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
uncertainty
propeller open-water test
lifting surface method
model-scale experiment
propulsion
Opis:
Within the frame of CTO’s standard procedure, a propeller open-water test is preceded by a reference measurement, which is taken for a reference propeller model (P356). The results of these measurements are assembled to conduct an open-water test uncertainty analysis. Additional material was gathered from open-water tests that were conducted throughout several research projects on the CP469 model, which is a model of the Nawigator XXI propeller. The latter is a controllable pitch propeller; its pitch was reset before each test repetition. Known procedures for the determination of the open-water test uncertainty do not allow one to extract the manufacture impact directly, without building many models. This factor was addressed with the use of lifting surface calculations. Under certain additional assumptions, these calculations were performed for 100 generic versions of each propeller’s geometry, which were generated by random deviations from the theoretical data within the limits of allowed tolerances. The results of the conducted analyses made it possible to extract separate factors, which were connected to the test’s repeatability, measurement bias and geometry tolerance.
Źródło:
Polish Maritime Research; 2022, 4; 4-11
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Neural Network Ensemble approach to pushed convoys dispatching problems
Autorzy:
Radonjić, Aleksandar
Pjevčević, Danijela
Maraš, Vladislav
Powiązania:
https://bibliotekanauki.pl/articles/259489.pdf
Data publikacji:
2020
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
Neural Network Ensembles
push boat
inland waterway transportation
full-scale speed/power trials
Opis:
This paper investigates the use of neural networks (NNs) for the problem of assigning push boats to barge convoys in inland waterway transportation (IWT). Push boat‒barge convoy assignmentsare part of the daily decision-making process done by dispatchers in IWT companiesforwhich a decision support tool does not exist. The aim of this paper is to develop a Neural Network Ensemble (NNE) model that will be able to assist in push boat‒barge convoy assignments based on the push boat power.The primary objective of this paper is to derive an NNE model for calculation of push boat Shaft Powers (SHPs) by using less than 100% of the experimental data available. The NNE model is applied to a real-world case of more than one shipping company from the Republic of Serbia, which is encountered on the Danube River. The solution obtained from the NNE model is compared toreal-world full-scale speed/power measurements carried out on Serbian push boats,as well as with the results obtained from the previous NNE model. It is found that the model is highly accurate, with scope for further improvements.
Źródło:
Polish Maritime Research; 2020, 1; 70-82
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vehicle-deck fires aboard RoPax ships: a comparison between numerical modelling and experimental results
Autorzy:
Salem, Ahmed
Powiązania:
https://bibliotekanauki.pl/articles/259491.pdf
Data publikacji:
2019
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
vehicle-deck fires
RoPax ships
zone models
field models
model-scale fire tests
Opis:
According to an official study conducted by the IMO Correspondence Group on Casualty Analysis concerning the fire incidents that occurred on the vehicle-decks of RoPax ships, covering the period from 1994 to 2011, it has been shown that a very serious incident has occurred every other year since 2002, resulting in six constructive total losses. The results of this review shed the light on the need to investigate the application of fire models to simulate fire scenarios that may occur on the vehicle-decks aboard RoPax ships. This will be very useful for the RoPax designers who are willing to introduce new technologies or deviate from the current prescriptive regulations of fire safety design in order to reduce the risk of such catastrophic accidents. The aim of this paper is to present the results of a comparison between the predictions of three different fire models and the experimental results of a model-scale fire test that represents a fire scenario on a vehicle-deck aboard a RoPax ship. A statistical analysis technique was used to illustrate the ability of each fire model to predict five outputs of concern. The main conclusion of this comparison is that there is always an optimal fire model that can predict one or more of the five outputs of concern with results in good agreement with the measured values.
Źródło:
Polish Maritime Research; 2019, 2; 155-162
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fault diagnosis of me marine diesel engine fuel injector with novel IRCMDE method
Autorzy:
Shi, Qingguo
Hu, Yihuai
Yan, Guohua
Powiązania:
https://bibliotekanauki.pl/articles/34608122.pdf
Data publikacji:
2023
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
marine diesel engine
fuel injector
improved refined composite multi-scale dispersion entropy
fault diagnosis
Opis:
As an important component of the fuel injection system, the fuel injector is crucial for ensuring the power, economy, and emissions for a whole ME (machine electronically-controlled) marine diesel engine. However, injectors are most prone to failures such as reduced pressure at the opening valve, clogged spray holes and worn needle valves, because of the harsh working conditions. The failure characteristics are non-stationary and non-linear. Therefore, to efficiently extract fault features, an improved refined composite multi-scale dispersion entropy (IRCMDE) is proposed, which uses the energy distribution of sampling points as weights for coarse-grained calculation, then fast correlation-based filter (FCBF) and support vector machine (SVM) are used for feature selection and fault classification, respectively. The experimental results from a MAN B&W 6S35ME-B9 marine diesel engine show that the proposed algorithm can achieve 92.12% fault accuracy for injector faults, which is higher than multiscale dispersion entropy (MDE), refined composite multiscale dispersion entropy (RCMDE) and multiscale permutation entropy (MPE). Moreover, the experiment has also proved that, due to the double-walled structure of the high-pressure fuel pipe, the fuel injection pressure signal is more accurate than the vibration signal in reflecting the injector operating conditions.
Źródło:
Polish Maritime Research; 2023, 3; 96-110
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The influence of hydro-meteorological factors on the risk of harbour operations
Autorzy:
Abramowicz-Gerigk, T.
Powiązania:
https://bibliotekanauki.pl/articles/258690.pdf
Data publikacji:
2007
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
harbour operations
hydro-meteorological elements
model tests of self-berthing
real scale experiments
safety of navigation
ship motion simulation
Opis:
The paper presents a study on the environmental impact on the risk of harbour operations. The hydro-meteorological elements have been recognised as the most important safety factors with regard to the ship entrance into the harbour and berthing inside the docks. They are identified as real time, short and long term factors and they all should be considered in the safety assessment of harbour operations. The risk of each operation should be determined on the basis of weather forecast and the modelled prediction of the total water level, surface currents and waves. Several topics have been discussed in the paper with regard to the safe ship approach and navigation inside the harbour. The application of different tools for the prediction of ship performance is presented. The stochastic method for the determination of probability that the ship will navigate within the boundaries of the required navigational width and low speed manoeuvring standards proposed by Panel H-10 SNAME have been considered. The real scale experiments carried out in Port of Gdynia and the several trials performed using the Full Mission Simulator convinced that the open water model tests are necessary for the proper prediction of ship performance during berthing. The program of the proposed open water investigations is presented in the paper. The experimental stand constructed for the tests of ship-berth interactions, in the lake Silm at the Ilawa Ship Handling Training and Research Centre facilities is described.
Źródło:
Polish Maritime Research; 2007, S 2; 33-37
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Model tests for shallow-water ship maneuverability in Three Gorges Reservoir
Autorzy:
Cai, C.
Cai, X.
Li, Y.
Powiązania:
https://bibliotekanauki.pl/articles/259922.pdf
Data publikacji:
2015
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
shallow-water test of ship model
simulated computation
maneuverability calibration
scale effect
Z shape test
K and T indexes
navigation safety
Opis:
This paper conducts calibration tests on the shallow-water maneuverability of 1:100 ship models for the typical navigation fleets in Three Gorges Reservoir. Major influential factors for the maneuverability similitude between models and prototypes and for scale effect were identified. A correction method for model scale was also established through model tests. Test results indicate that, by correcting the model scales of various fleets based on scale effect, the maneuverability indexes K’ (dimensionless of K) and T’ (dimensionless of T) of ship models are suitable for shallowwater tests, and properly reflect the maneuvering characteristics of prototypes. The findings provide an experimental basis for the navigation safety in Three Gorges Reservoir.
Źródło:
Polish Maritime Research; 2015, S 1; 136-140
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-12 z 12

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