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1
EN
Wind energy is a clean and renewable source of energy. This study seeks to explore the potential for utilising wind power for merchant ships. A new type of Flettner rotor (rotating cylinder) mounted on the superstructure of a ship is proposed and numerically simulated. The construction and installation of the rotating cylinder is designed and a numerical simulation of the ship-mounted cylinder is carried out, using the commercially available CFD code Ansys Fluent to obtain parameters such as lift and drag coefficient of the cylinder in different conditions. Specifically, it is found that the cylinder type superstructure can play a certain role in reducing the effect of friction by comparing traditional and cylindrical superstructures; the rotating cylinder can generate auxiliary thrust for the ship. After analysis, the wind speed around the cylinder and spin ratio will have a direct influence on its thrust effect; there is an inflection point in the lift coefficient with the increase of α; the thrust coefficient (8.63) reaches the maximum environmental wind speed at 10 m/s and spin ratio is 2.5. For the rotating cylinder, the greater the environmental wind, the greater the thrust contribution generated under the same spin ratio conditions. The maximum thrust can reach 750,000 N; the cylinder’s auxiliary propulsion contribution shows a better advantage in α = 2.0. The effective power generated by the cylinder reaches a maximum of 2,240 kW for environmental wind speed = 20 m/s and α = 1.0.
EN
This study addresses the problem of training the officers, which are assigned to an electrical-driven vessels equipped with azimuth thrusters. A pair of omnidirectional thrusters in combination with power plant system containing several diesel generators imply a potential for a variety of different emergency scenarios, which also includes partial or full loss of control or blackout. These fault scenarios were classified in the article with predefined risk levels depending on the area, time limitation, mode of operation and fault itself. Mutual responsibilities and action algorithms for bridge and engine teams in a step-by-step manner have been developed for each scenario. Personnel behavioral differences in both expected and unexpected emergencies have also been studied.
PL
Artykuł dotyczy problematyki ograniczania emisji substancji gazowych i pyłowych na statkach śródlądowych w związku z nowymi uregulowaniami prawnymi i technicznymi obowiązującymi na obszarze Unii Europejskiej. Jednym z kierunków spełnienia norm ochrony środowiska, w tym normy STAGE V, jest stosowanie paliw alternatywnych w napędach nowo budowanych statków śródlądowych lub stosowania instalacji ograniczających emisje szkodliwych substancji do atmosfery na statkach będących w eksploatacji kilkadziesiąt lat. Celem artykułu jest analiza wybranych rozwiązań napędowych i możliwości ich wdrożenia w najbliższych latach, aby dostosować tabor pływający do nowoczesnych wymagań technicznych oraz obniżyć ich koszty eksploatacji. W artykule przedstawiono dotychczas stosowane rodzaje napędów na jednostkach śródlądowych oraz uwarunkowania prawne określające warunki wdrażania paliw alternatywnych i stosowania technologii ograniczających emisje spalin. Przeanalizowano wybrane paliwa alternatywne oraz możliwości ich zastosowania w napędach statków śródlądowych. W ostatniej części rozpatrzono aspekt ekonomiczny zastosowania gazu naturalnego jako paliwa i jego wpływ na korzyści armatora statku śródlądowego.
EN
The authors of the article raise the issue of limiting the emission of gaseous and dust substances on inland vessels in connection with new legal and technical regulations in European Union. One of the directions of meeting environmental protection standards, including STAGE V, is the use of alternative fuels in drives of newly built inland vessels or the use of installations limiting emissions of harmful substances to the atmosphere on vessels in operation for several decades. The aim of the article is to analyze selected drive solutions and the possibilities of their implementation in the coming years to adapt the fleet to the modern technical requirements and reduce their operating costs. The article presents hitherto used types of drives on inland units and legal conditions defining for the implementation of alternative fuels and the use of technologies limiting exhaust emissions. In addition, were analyzed selected alternative fuels and options for their use in inland waterway vessels. The last part deals with the economic aspect of the use of natural gas as a fuel and its impact on the benefits of the owner of an inland vessel.
4
Content available remote Elektryczne pędniki wieńcowe
PL
W pracy przedstawiono nowy rodzaj pędników okrętowych mogących mieć różnorodne zastosowania na jednostkach pływających: od sterów tunelowych poprzez pędniki manewrowe po napęd główny. Kolejno opisano historię powstania pędnika, jego odmiany i konstrukcję oraz przedstawiono cechy charakterystyczne takiego napędu, w zakończeniu pokazując przykładowe rozwiązania fabryczne.
EN
A new concept of the marine thrusters are presented. The history of the product is shown at the beginning. The construction of the thruster and the exploitation characteristics are described later. The commercial products offered by a few firm are presented in the final part of the paper with the short description of the first ship with the rim-driven thruster as a main propulsion system.
EN
This article shows the importance of the diagnostic improvement methods of marine engines to boost the economy and safety of operation of marine cargo ships. The need to implement effective diagnostic methods is justified by presenting statistical data of marine diesel engines failure and the cost of their operation. Based on the own research has been proven, for the chosen example, that indicator diagrams and analysis of indicated parameters have limited utility in the diagnosis of damages of marine engine, although this is a method commonly used in operational practice. To achieve greater diagnostic effectiveness, when, based on indicator diagrams, are calculated and then the characteristics of heat release is analyzed - net of heat release characteristics and the intensity of the heat release, it was demonstrated. This procedure is particularly effective in the diagnosis of damage of injection system components marine diesel engine.
EN
In terms of electric ship energy requirement in navigation, the ship charging station location is especially important. In this paper, a multi-period ship charging station location optimization model is pro-posed to make location decision in overall, from initial possible station sites chosen to the capacity determination for the final location sites. In the first phase, from the perspective of external environment, find out all possible ship charging station candidate sites through the feasible analyze. In the second phase, taking the ship charging demands into consideration, the final ship charging station sites can be selected among the candidate sites based on backup coverage model. In the last phase, regarding the cost of construction and service capability for different grade as the main factor in capacity determination, the optimal capacity of each final ship charging station are determined by means of optimization method. Finally, an example of Yanqi lake in China is used to verify the validity of the proposed methodology. The reasonable location of charging station could ensure the electric energy supply and avoid congestion caused by ship charging gathering. The model can be easily generalized to other problems regarding facility allocation based on user demand.
EN
The development and growing availability of modern technologies, along with more and more severe environment protection standards which frequently take a form of legal regulations, are the reason why attempts are made to find a quiet and economical propulsion system not only for newly built watercraft units, but also for modernised ones. Correct selection of the propulsion and supply system for a given vessel affects significantly not only the energy efficiency of the propulsions system but also the environment – as this selection is crucial for the noise and exhaust emission levels. The paper presents results of experimental examination of ship power demand performed on a historic passenger ship of 25 m in length. Two variants, referred to as serial and parallel hybrid propulsion systems, were examined with respect to the maximum length of the single-day route covered by the ship. The recorded power demands and environmental impact were compared with those characteristic for the already installed conventional propulsion system. Taking into account a high safety level expected to be ensured on a passenger ship, the serial hybrid system was based on two electric motors working in parallel and supplied from two separate sets of batteries. This solution ensures higher reliability, along with relatively high energy efficiency. The results of the performed examination have revealed that the serial propulsion system is the least harmful to the environment, but its investment cost is the highest. In this context, the optimum solution for the ship owner seems to be a parallel hybrid system of diesel-electric type.
EN
Unavailability of a ship propulsion system under aging effects and proper maintenance is estimated using GO-FLOW. GO-FLOW is an effective software tool for the unavailability analysis of complex systems. Aging effects are incorporated into GO-FLOW using a time-dependent technique and assuming a linear aging model. The results show that the aging effects and improper maintenance can potentially increase the frequency of accidents due to a malfunction of the propulsion system by a factor of three.
PL
W artykule scharakteryzowano problem wyznaczenia charakterystyk napędowych układu napędowego statku ze śrubą o stałym skoku, rozpatrując w pierwszej kolejności charakterystykę momentu. Modelowanie charakterystyki momentu oparto na opublikowanych modelach aproksymacyjnych z badań śrub swobodnych. Do weryfikacji modeli wykorzystano dostępne w literaturze przedmiotu wyniki badań układu napędowego statku m/s „Garnuszewski”. Wyłoniono pięć porównywalnych statystycznie modeli charakterystyk momentu obrotowego, z których trzy modele dają zbieżne charakterystyki momentu obrotowego na uwięzi, wyznaczone drogą ekstrapolacji. Pokazano, że pozostałe charakterystyki: charakterystyka mocy oraz charakterystyka jednostkowego zużycia energii na milę morską powinny być wyznaczane ze wzorów definicyjnych po wyznaczeniu charakterystyki momentu. Zwrócono uwagę na potrzebę każdorazowego wykonywania analizy statystycznej wyników badań.
EN
The paper characterized the problem of finding propulsion characteristics of the propulsion system with a fixed pitch propeller, considering first the torque characteristics. Torque characteristics modelling based on published research approximation models of the open-water propeller. Test results of propulsion system of ship MS “Garnuszewski” were used for models verification. In total, five statistically comparable models of torque characteristics were developed, of which three models produce consistent results of tethered torque characteristics, obtained by extrapolation. It has been shown that the other characteristics: power characteristics, characteristics of specific energy consumption per nautical mile should be determined with definitional formulas after determining torque characteristics. Drew attention to the need for statistical analysis research results.
EN
TEU number, which is the container ships’ crucial designing factor, directly influences the main hull dimensions such as displacement V , length L, breadth B, draught T, their combinations and block coefficient CB. The main dimensions have a great impact on developing the ships resistant performance. Thus, it is really fundamental to establish the correct dimensions of the hull during the design and ship building process. Estimating the shape of the ship’s hull, that comprises its main dimensions, is one of the basic tasks as part of the preliminary design stage. The most significant decisions determining ships performance, its duration and building costs are made at the beginning of the preliminary stage, when the costs are relatively low. It is important to limit the total ship resistance, for instance, by lowering the wave ship resistance as much as possible, especially when the operational speed and TEU number carried by one vessel is increasing. That resistance depends on the operational speed expressed by Froude number. The resistance criteria and the existing hull dimensions limits, resulting from ships route, must be taken into consideration bearing in mind safety conditions such as ships stability and seaworthiness, when the main ships dimensions are being determined. In the paper are presented general rules for calculations of ship’s hull principle dimensions and total power of engines of container ship 1300TEU and 18 kn at preliminary stage of design process.
EN
The pseudo-entropy hybrid model is suggested as the measure of uncertainty of operators' subjective preferences. Because of the introduced relative prevailing preferences factor the proposed hybrid model has advantages comparatively to the traditional measures of uncertainty in the view of Boltzmann's or Shannon 's entropy. According to the relative dominating preferences index the pseudo-entropy varies within [-1...1] showing the sign and magnitude of the relative subjective assuredness. Analytical expressions have been achieved. The theoretical concept is illustrated with examples and graphs.
EN
In the Faculty of Ocean Engineering and Ship Technology, Gdansk University of Technology, design has recently been developed of a small inland ship with hybrid propulsion and supply system. The ship will be propelled by a specially designed so called parallel hybrid propulsion system. The work was aimed at carrying out the energy efficiency analysis of a hybrid propulsion system operating in the electric motor drive mode and at performing the noise pollution measurements. The performed investigations have shown that a significant impact on the efficiency and on the acoustic emission has the type of belt transmission applied.
13
Content available remote Optimization of Hybrid Propulsion Systems
EN
Powertrain hybridization permits the benefits of more than one power source to be integrated and exploited for a beneficial effect on an objective, such as reduction of fuel consumption or emissions. Due to their operating profiles however, marine hybrid vessels do not exhibit much opportunity for free energy re-cuperation. Fuel savings can be realized by bettering component operating points, yet this requires correct siz-ing matched to the expected usage. In this paper, a multi-objective genetic algorithm is used to optimally size propulsion components in order to minimize fuel consumption as well as installation weight for a hybrid mo-toryacht operating on a day cruise scenario.
EN
This paper proposes a new drive system for the ship propulsion. The drive power for propelling ship varies from few MW in a small cruise ship to hundreds of MW for large cargo ships. A typical cruise ship has a 6 MW drive whereas a cargo ship has 80 MW drive. Combustion drives are not sustainable and environment friendly. An idea of electric drive system using hydrogen fuel cell and necessary storage has been proposed. The hydrogen reformer develops hydrogen fuel cell using off-shore renewables like Wind, Wave and Solar power but the power handling capability of this fuel cell system (100 kW) restricts the application to the propulsion drives of several MW. The detail drive scheme describing; how multiple modular hydrogen fuel cell drives are integrated to develop variable power. The different options available for the propulsion system and factors affecting the choice are discussed in detail. Also, how such modular drives are helpful in controlling torque and power requirements is discussed. Replacement of electric drive reduces volume and weight of the ship and the available volume can be utilized for the storage and reform systems. The proposed paper will give a remarkable concept to overcome the challenges of utilizing hydrogen fuel cell to the larger scale and in future it can be extended to all other applications.
EN
This paper presents a concept of a ship combined high-power system consisted of main piston engine and steam turbine subsystems, which make use of energy contained in exhaust gas from main piston engine. The combined system consisted of a piston combustion engine and an associated with it steam turbine subsystem, was considered. The system’s energy optimization was performed from the thermodynamic point of view only. Any technical –economical analyses were not carried out. Numerical calculations were performed for a Wartsila and MAN Diesel & Turbo low-speed diesel engine of about 50 MW output power.
EN
This paper presents a detailed mathematical model of ship propulsion system including slow speed diesel engine, screw propeller and governor. This mathematical model is then employed to investigate the system performances both in steady state and unsteady states. The simulation results are checked and the model is verified using experimental data. Next an original method for the system sensitivity analysis against changing of parameters is given. This method is finally applied for investigating the influence of degree of reaction of turbine of turbocharger on the system behaviour.
17
Content available LNG as a marine fuel - possibilities and problem
EN
The limitations of marine fuels use incorporated sulphur on levels 4-5% for HFO and 0.5-1% for MDO were caused a necessity of possessing on ship a few types of fuel: conventional and with limited amount of sulphur. It is a necessary to separate the installation of different fuels caused that the ship fuel system are complicated. It is needed to change the fuel with time advance on areas with SOx controlled emissions (SECA areas) for example Baltic and North Sea. In the same time it is needed to change the engine adjustment in the aim of decreasing NOx emission. It allows for fulfilling the emission on tier 2 level (IMO regulations). It was announced for January 1st 2016 the time of tier 3 requirement of being in force. It is seemed to be impossible the fulfilling of that standard on marine liquid fuels (HFO and MDO). It was interested on gas fuels, especially on popular one the liquid natural gas (LNG). In the liquid state LNG is seemed to be an attractive marine fuel. It is remaining a problem of marine engines adaptation for burning that type of fuel in the aim of fulfilling the tier3 standard. At present, available dual fuel for marine diesel engines burn natural gas for ship operating reasons. Fulfilment these requirements needs an engine modernization or the alternative way is use of piston spark engines. There is an additional problem the assurance of repeatability of natural gas combustion process. During the change of engine load changes the fuel-air mixture composition, it is heterogeneous in the cylinder volume caused the ignition loss, the knocking combustion and the risk of out-of-control fuel self-ignition. The paper presents a probe of analysis these problems.
EN
The cost of ship operation is dominated by the cost of fuel. The efficiency of ship propulsion depends on number of parameters. After selection of the most important we can further analyze them for taking relevant action to increase the ship propulsion efficiency. Biofouling of underwater part of ship’s hull has direct influence on vessel resistance and engines power required to maintain the speed or keep optimal fuel consumption. HISMAR is a name of the project directed on development of robotic system that can be used to introduce new approach to keep ship hull clean and almost free of bio-fouling. Frequent cleaning using HISMAR robotic system could be a new tool to increase ship performance as well as conduct specific types of ship hull surveys underwater. New approach for inspection and cleaning needs field research to validate the financial and technical benefits. The HISMAR Project no 012585 was founded by EU-FP6 Framework Program.
EN
The paper presents the study on the effectiveness of ship propulsion devices based on model tests conducted in the open water experimental set up. The influence of the water depth to draft ratio and distance from the vertical tight wall on the hydrodynamic forces generated by the propellers on the ship hull was investigated. The interaction effects observed for the twin propeller ship in bollard pull condition were compared with the effects induced by single propeller vessels available in literature and discussed with respect to the mathematical modelling of hydrodynamic forces generated on the hull by ship propulsion devices.
EN
This paper concerns an algorithmic method for preliminary selection of parameters of ship propulsion system fitted with fixed screw propeller in the case when the ship’s operation is associated with significant changes of waterway depth and width, hull resistance of the ship and its service speed. Mathematical model arguments of the considered design problem are main ship design parameters identified in the preliminary design stage. Structure of the formulated model complies with formal requirements for continuous- discrete mathematical optimization problems. The presented examples of application of the method concern an inland waterways ship fitted with compromise screw propeller optimized in the sense of minimization of fuel consumption for passing a given route distance within a given time. The elaborated method may be especially useful in designing such ships as : coasters, inland waterways ships, tugs, pushers, trawlers, mine sweepers, icebreakers etc.
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