Items · Journal of Marine Technology and Environment

THE PREDICTION OF NOX EMISSIONS FROM DIESEL ENGINES BASED ON TWOZONE THERMODYNAMIC MODEL

Dawwa MAHRAN; Bocanete PAUL

4/1/2016

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

In this study a two-zone thermodynamic model is used for the prediction of NOx emissions from marine diesel engines, the calculation of two-zone model will be based on one-zone thermodynamic model and on the use of Zeldovich mechanism. The calculated NOx emissions validated by comparing them with measured values at different engine operating regimes. The effect of cylinder wall temperature, air temperature coefficient, and residual gases coefficient on the model sensitivity will be illustrated and explained as well.

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A CFD STUDY ON THE EFFECT OF INJECTION PARAMETERS ON THE FORMATION OF NOX EMISSIONS IN DIESEL ENGINES

Dawwa MAHRAN; Bocanete PAUL

4/1/2016

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The objective of this study is to predict the effects of two main injection parameters on the formation of NOx emissions. The first parameter is the injection timing, the effects of injection timing on the formation of NOx emission will be illustrated and explained at four different injection timings. The second parameters is the cone angle, the effect of changing the cone angle on the formation of NOx emissions will be illustrated and discussed at different three cone angles as well. Computational fluid dynamics (CFD) and ANSYS ICE program were used for simulating the injection process, combustion, and the formation of NO. The Volume-average mole fraction of NO, the Mass-Average mass fraction of NO and the NO density will be discussed at all cases of injection parameters..

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MANAGERIAL ANALYSIS OF ENERGY EFFICIENCY STANDARDS’ IMPLEMENTATION ON BOARD TO OPERATING SHIPS

Drd. Doru COSOFRET ; Dr. Florin Marius NICOLAE; Dr. Catalin POPA

4/1/2016

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Since 2013, together with the Resolution MEPC.203 (62)/2011 IMO enforcement, the vessels in service top and operational management must adopt the necessary measures to increase energy efficiency on board the ships in order to comply with the standards imposed. In this order, subscribed to a wide study in this mater, the present paperwork is focused punctually on the holistic analysis of the optimum energy efficiency measures that can be implemented at managerial level, on board the commercial vessels in service, operating more than 20 years. Through the proposed measures, the overtaken analysis provides the prerequisites for an efficient tool in shipping business management, providing a useful working framework, grounded in theory and practice, for adopting the optimum decisions to assure the energy efficiency on board the operating ships, targeting the ratio between lowest costs and best economic performance.

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ADOPTING OF SENSORS WITH AMORPHOUS RESISTIVE LAYERS IN ELECTRICAL MEASURING OF SPEED OF FLUIDS IN SHIPS

Bohos APRAHAMIAN

4/1/2016

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

New resistive elements, formed upon electro insulated plate of vacuum thick ceramics by magnetron sputtering or screenprinting of amorphous resistive layers are studied. The elements possess a relay-type strong negative temperature dependence of resistivity. The new elements are adopted as sensors in standard bridge circuits for measuring of speed of fluids. Prototypes of sensors with various compositions of amorphous metal layers are analyzed and compared. The new elements show better sensitivity compared to a standard sensors.

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ELABORATION AND TESTING OF LABORATORY STAND FOR INVESTIGATION OF AN ARC FAULT DETECTION DEVICE

Bohos APRAHAMIAN

4/1/2016

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The arcing faults may have a severe impact on the ship or on the crew. The paper presents the elaboration and testing of a laboratory stand for investigation of an arc fault detection device in the Technical University of Varna, Bulgaria. The presented laboratory stand will train future electrical engineers to work with this new protection device.

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APPLICATION OF PROTECTIVE TIN COATINGS ON COPPER AND ALUMINUM LOW VOLTAGE BUSBARS OF ELECTRICAL DISTRIBUTION BOARDS OF SHIPS

Bohos APRAHAMIAN

4/1/2016

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

In this study an opportunity for investigation and application of protective monolayers of TiN obtained in reactive arc method in N2 atmosphere is examined. The coatings are deposited on copper and aluminium low voltage busbars of electrical distribution boards. The aim is to reduce the contact-potential difference between the busbars, made of different metals, i.e. copper and aluminium and, thereby, to reduce the power losses. The article also presents the results of studies of corrosion resistance, in particular the resistance to salt sea mist of the coated busbars. The possibility of using these busbars at sea has been experimentally proven.

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PHOTOVOLTAIC CELLS - PROJECT OF USING THEM ON CARGO SHIPS

Mihail - Vlad VASILESCU

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The main focus of this article is the development and use of clean renewable energy sources on ships. The main goal is the diversity of energy sources and the reduce of environmental pollution, hoping that this will ensure future energy security of supply. I propose to install the solar panels on a port-container. The reason of this article is to try to reduce ship pollution and the quantity of fuel used, that mince, to reduce the price of transportation and to save money. As a result of my research I discovered that is more convenient to use the Rawlemon photovoltaic sphere that normal solar panels. Photovoltaic sphere is generating energy by day and night, in all types of weather. It has a yield with 70% higher than normal photovoltaic panel attached to a fixed mount, it can generate upto 3.4 kWh/day. Environmental impact of photovoltaic field is limited to space used and to the visual impact because there are nil polluting emissions, thermal or acoustic. Photovoltaic sphere is revolutionizing photovoltaics panels, it captures the Sun rays on the opposite side of the sphere acting as a lens which focuses them on a large area directly to the solar panel. Action on energy efficiency is one of the fastest and most effective ways to support improving the performance of companies with respect the protection of environment. Energy is one of the most controllable costs, because any energy savings are accounted directly into profits.

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ANALYSIS ON THE OFFSHORE WIND IN THE EUROPEAN MIX ENERGY

Liviu-Constantin STAN

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The energy sector of a country is stronger when multiple ways of producing energy exist, so when there are multiple systems of energy and is less resistant when there is only one way of applied producing energy. The solution for the future stability of everyday life is from the energetic point of view, the existence of several energy systems in parallel. In this system, the renewable energy sources (RES) play an increasingly important place, contributing to a sustainable and efficient development, compatible with a cleaner environment. Among these energy sources, the marine RES, which include both offshore wind and ocean energy, become from one year to another, important resources generating economic growth and jobs enhance the security of its energy supply and boost competitiveness through technological innovation. Between the both marine RES sectors, it is distinguished the importance of the offshore energy that increases year by year. The figures that will be presented in the paper are relevant in this sense. The paper contains a desk analysis of the offshore energy area, showing figures, images, dates and conclusions on these new technologies and their effects on short and long terms. Also, a SWOT analysis is included, representing a necessary assessment of the strong and weak points, trying to adjust the strengths to the opportunities and reduction at a minimum level of the threats, eliminated the weak points. The projects based on this type of energy source, its positive results outline a promising perspective for the investors and authorities. The benefits are conclusive in this area: this inexhaustible and free resource generates energy with zero emissions, provides permanent and temporary jobs, services and economic growth, a balanced proportion between supply and demand of energy.

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BLUE ENERGY IN THE SEAS AND OCEANS

Liviu-Constantin STAN

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The seas and oceans have the potential to become important sources of clean energy. Marine renewable energy, which includes both offshore wind and ocean energy, presents an opportunity to generate economic growth and jobs, enhance the security of the energy supply and boost competitiveness through technological innovation, contributing to the decarbonisation goals. In the context of a decrease of the primary resources, the blue energy generated by the oceans and seas captured the interests of many countries. We see today many studies, researches, projects that crossed the borders of the countries, developed by collaborative mixed teams. The results are promising, the success is guaranteed. The present paper is a desk research on the ocean energy in Europe and not only in this region, showing the best practices in this area of activity and their implementation. The conclusions are very clear and sustained by the figures; the blue energy gained its own place in the mix energy of many countries. This inexhaustible resource seems to gain more and more interests year by year.

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COMPUTATIONAL FLUID DYNAMIC ANALYSIS OF MARITIME CONTAINER TERMINALS

Laurentiu OANCEA; Dumitru DINU

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The existing movement for the reduction of environmental impact and improvement of efficiency of processes, lead to a need for optimizing the transport and logistic chains. Here it is presented a possible approach for using Constructal Theory in order to develop an alternative for shape optimization and access to the storage area in a container terminal for reaching sustainability. The approach consist on the utilization of the Constructal Theory for generating optimized geometrical shapes of the container storage area. The analysis shall be made based on the analogy between transport systems and fluid dynamics, which can be transferred for advanced analysis in a FEM application. The results will show the possibility presented by this kind of application for the overall optimization of transport systems and reduction of transport times, thus decreasing the impact on the terminal and reducing GHG emissions.

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METHOD OF CHOOSING A BETTER ROUTE IN SHIPPING

Tomasz NEUMANN

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

This paper presents a different view on the evidence theory and Dijkstra's algorithm. In this paper, the algorithm will be used in the further analysis to additional paths between nodes can be found in the maritime sector. In many cases, the best solution for a single criterion is not sufficient. It would be search for more effective solutions of the starting point to use for subsequent analysis or decision of the captain of the vessel. With innovative thinking mechanisms it is possible to create a decision support system based on known Dijkstra's algorithm. Reasoning mechanism is based on the theory of evidence. The intervals were used, where interval means a set of real numbers with the property that any number that lies between two numbers in the set is also included in the set.

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ELABORATION OF THE AUTOMATIC VOLTAGE REGULATORS OF THE SHIP SYNCHRONOUS GENERATORS

Todor LAZAROV

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

In order to raise the effectiveness of the energy system an electronic voltage regulator with a high speed operation can be installed. An original AVR scheme which uses, which uses proportional-integral-differential control and pulse-width modulation scheme to control the output voltage of the compound system, is presented. The scheme of the electronic regulator is enclosed.

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MONITORING SYSTEM FOR CONTROL, REGISTRATION AND MANAGEMENT OF ENERGY QUALITY INDICATORS IN SHIP POWER SYSTEMS

Ginka IVANOVA; Bohos APRAHAMIAN; Valentin GYUROV

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The paper presents the structure and operation of a developed mobile monitoring system for analysis, control, registration and management of the energy quality indicators in the ship electrical power systems. The system was successfully tested in the Ship’s Electric Drives Laboratory of the Technical University of Varna.

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ANALYSIS OF THE OPERATING SOFTWARE USED FOR WEATHER ASSESSMENT ON BOARD OF THE SHIP

Ivaylo GRANCHAROV ; Belev BLAGOVEST

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Nowadays, many computer agencies offers to the companies operating in the maritime field as ship owners, ship operators and charterers, various services related to the processing of meteorological information. However the use of competent meteorological advisory company did not relieves the master and navigating officers from responsibility concerning the safety of the ship, lives of crew members and condition of the cargo. This paper discusses the companies, software and internet sites, which presents a great amount of meteorological information to the ship business. The obtained meteorological information can be used on board of the ship for: voyage planning by masters; planning the duration of the voyage and calculation of the fuel coast by ship owners; raising a claim by charterers concerning the insufficient speed of the vessel as agreed in charter party, or for any other calculation and predictions relating shipping. Some of these services are free of charge while the others required regular payment. On board of the modern vessel, using new satellite technologies, it is a matter of minutes to obtain the required meteorological information.

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THE EVOLUTION OF AN ACCIDENTAL RELEASE OF OIL, NEAR BURGAS

George-Laurentiu DUMITRESCU; Ionut VOICU; Fanel-Viorel PANAITESCU; Mariana PANAITESCU

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

In this paper it is presented a computer simulation for a possible prediction of an oil slick near Burgas harbor. The simulation it is carried out using POTENTIAL INCIDENT SIMULATOR EVALUATION AND CONTROL SYSTEM (Pisces II) which is a software, especially designed for assessing the consequences of oil pollution on sea water. PISCES is an incident response simulator designed for preparing and conducting command centre exercises and area drills. The application is developed to support exercises focusing on oil spill response. The model takes into account the main physicochemical processes occurring in the oil slick, which include evaporation, dispersion, emulsification and viscosity variation. Simulation is carried out with regard to the following environment factors: coastline, field of currents, weather, sea state, ice conditions and environmentally sensitive areas. In addition, models of response resource application including booming and recovery have been developed [1], [3], [4].

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OIL LEAKAGE SIMULATION AND SPILL PREDICTION NEAR ODESSA HARBOR

George Laurentiu DUMITRESCU; Ionut VOICU; Fanel-Viorel PANAITESCU; Mariana PANAITESCU

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The paper presents a computer simulation of an emergency situation generated from an oil spill, inside Odessa harbor, using the software POTENTIAL INCIDENT SIMULATOR EVALUATION AND CONTROL SYSTEM (Pisces II), who it is especially designed for assessing the consequences of oil pollution on sea water.

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STATISTICAL MODEL OF A LNG TERMINAL – WAYS OF IMPROVING THE LNG TERMINAL EFFICIENCY

Dimitar DIMITRAKIEV; Rumen GROZEV

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The best way of improving the efficiency is to create a basic statistical model which can be used in the future for optimizing the work of a new terminal in the near future. The proposed model represents LNG terminal as queuing system. The model created is basic one but can be used as good foundation for creating a more sophisticated model once the main characteristics of the a new LNG terminal are known.

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PROBABILISTIC METHODS OF DECISION MAKING IN SHIPPING ACTIVITIES

Dimitar DIMITRAKIEV

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

When studying a large number of phenomena and processes, researchers strive to create simple patterns. From the wide variety of factors separate the main and the rest are considered secondary and ignored. Very often, in practice, in making management decisions in the presence of many options is the task to recalculate the probability of each hypothesis, once it has been observed event. Such circumstances can be decided by the theorem to verify the hypotheses (Bayesian formula) obtained as a consequence of the theorem for multiplication formula for the total probability. Bayesian formula can calculate conditional probabilities of each hypothesis, then most likely of them is taken as the basis for future action. To obtain the practical utility of the theorem to check the hypothesis, we examined two cases of decision arising in shipping activity.

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APPLICATIONS IN MATLAB USING FINITE ELEMENT METHOD

Iulia-Alina ANTON; Mariana PANAITESCU; Fanel-Viorel PANAITESCU

10/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

Finite Element Method (FEM) is based on the concept of building complex objects using simple elements or division in small parts of complex objects easily manipulable. This paper presents the modeling equations of fluid and thermal analysis, namely equations type: hyperbolic, elliptical parabolic. It will be noted that it is important to know every step of the method as the main stage is the development model for calculating the structure. Other important steps are the domain meshing and interpolation process of meshing with the effect sharing model structure in a certain number of pieces called finite elements. Here, we will present three types of equations modeling using Matlab. Finally, we notice that there are several programs that are based on MEF instead with a user-friendly interface. Even here it is necessary to understand the method steps in order to properly model the model chosen.

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THE MATHEMATICAL DESCRIPTION OF THE PROCESS OF OIL SPREADING ON THE WATER SURFACE

Ionut VOICU; Laurentiu George DUMITRESCU

4/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The aim of this paper is to study and explain the spreading of oil on the water surface. Oil spills in sea waters are serious environmental disaster often leading to significant and long-term impacts on the sensitive aquatic systems. Having a detailed knowledge of oil slick behavior on water can be important in making operational decision and taking appropriate action against pollution. When crude or refined oil products are spilled on the sea, they are spread to form an oil slick. The slick spreads over the water surface due to a balance between several forces. A number of natural processes take place, which disperse the oil and change its chemical and physical properties.

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UTILIZATION OF RESOURCES ON TECHNO-NAUTICAL SERVICES BY DEVELOPING A DYNAMIC SIMULATION MODEL: AN APPLICATION ON THE PILOTAGE SERVICE IN ISTANBUL STRAIT

Lect. Capt. Emre UCAN; Assoc. Prof. Dr. Selcuk NAS

4/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

In Turkey, techno-nautical services’ principles are determined in Port Regulations prepared by Turkish Transportation, Maritime Affairs and Communication Ministry. But the principles are set mostly empirically or experience based. This study helps decision-makers and stakeholders for the correct utilization of resources on technonautical services by developing a dynamic simulation model. For this purpose, the pilotage service algorithm has been developed according to structured interviews with pilots, with statistical data of Traffic in Bosporus and all rules and regulations in effect on the waterway. It is found out that by the designed algorithm, it is possible to make correct decision about the required human resource as pilots even in a complex system as in Istanbul Strait. And due to dynamic nature of algorithm with application of simulation software different scenarios can be evaluated easily.

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MODEL OF PROCESS OF PORT INFRASTRUCTURE SAFETY MANAGEMENT

Evgeniy RUDENKO

4/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The article presents a model of process of port infrastructure safety management, based on proactive approach, which is defined as an activity, directed on maintenance and improvement of the future state of port infrastructure safety. Model is directly related to the adoption of project decisions, because provides the concordance of the put aims and chosen strategies through their realization. Proactive management is one of the basic principles of port infrastructure safety management, laid down in the proposed model. Proactive approach to port infrastructure safety management involves planning strategy of this activity by formation of a portfolio of projects that achieve strategic objectives of port safety improvement program. Proposed model of port infrastructure safety management allows effectively manage the current state of port infrastructure safety through measures aimed primarily at reducing the probability of an emergency, as well as to forecast and evaluate the future state of port infrastructure safety with regard to its development.

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DEVELOPMENT OF MATHEMATICAL MODEL FOR HUMAN RELIABILITY ASSESSMENT

Sabina NEDKOVA

4/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The assessment of the human reliability is an attempt to predict the behavior and the attitude of the man, which could lead to the realization of a critical situation. This is a complex process, mainly due to the fact that unlike machines which failures are predictable and easy to be identified because of the exact parameters that the process must have at any point in its development, when dealing with people, we cannot speak of "failures” in the purely technological sense of the word. Some of the most important reasons for that are: that the people’s work is often described qualitatively, but not quantitatively; in most of the cases the action carried out by a human is part of a process shaped by the actions of other people involved in it; and in the complex of factors, physical and psychological, personality-related, qualifications, experience and knowledge, as well as the environment and the nature of work, which affect the human in the performance of his duties.

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A POINT OF VIEW ON THE THEORY OF OPEN CYCLE GAS TURBINES

Feiza MEMET

4/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

In the context of the high interest on the concept of energy, engineering education has to adapt to the modern technical requirements. In this respect, marine engineering, as a part of engineering education is facing curricula changes. This paper deals with an attempt related with the improving of the teaching syllabus of the discipline called Thermodynamics / Part 1, included in the curricula of future marine engineers, enrolled in Constanta Maritime University (CMU). More exactly, it is about the theory of open cycles of gas turbines. The need of improving this theory came from the fact that in the last decades, this technology became more and more attractive for different industries. Maritime industry is one of these, where it is registered a high interest for thermal performance improving. Thus, if the classic theory of open cycles gas turbines was based on considering the working fluid to be a perfect gas, having constant specific heats, the new approach is discussing the case of irreversible cycle and specific heats of air and flue gas depending on temperatures. Results the need of a new hour allocation. This theoretical basis is allowing a more detailed thermal efficiency evaluation and assessment of specific fuel combustion.

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VELOCITY OVER THE TARGET SURFACE AND PRESSURE FOR A NUMERIC GEOMETRY OPTIMIZATION OF AN WED

George MARTINAS; Andreea ARSENIE; Marinel Danut LAMBA

4/1/2015

Marine sciences and engineering; Renewable energies; Marine renewable energies and Sustenability; Advanced technologies for MET; Climate changes

The pressure on ships designers to achieve both reduced fuel costs and reduced emissions by optimizing the hull and propeller has never been higher. Being one of the key strategic business goals for ship owners and operators, the reduction of fuel cost becomes essential; and furthermore a variety of recent legislations require owners and operators to move towards the reduction of emissions from ships of SOx, NOx and CO. There has been great interest in the potential to enhance the performance of existing vessels through retrofit of devices to the hull, in parallel to the performance improvement of new built vessels. The Wake Equalizing Duct (WED) device must be customized to fit to the afterbody of the ship in terms of performing its supposed function as Velocity over the Target Surface and Pressure. The Designer is therefore placed in the front of multiple geometric solutions from between he has to make a choice. A given geometry of a WED device is taken and via Design Optimization the geometry of the duct was refined so that better results are achieved with a smaller and more compact WED. A rational choosing approach by involving the numeric optimization of the geometry of the WED in order to select the best fitted WED to perform the best in order to achieve some predefined parameters is targeted in this papers.

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