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Open access

Mariusz Giernalczyk, Filip Łoński and Wojciech Kaniak

Abstract

This article attempts at assessing the feasibility and validity of adjusting the two-stroke diesel engine to be fuelled by liquefied natural gas (LNG). It discusses a set of modifications introduced onto one of the ships carrying liquefied natural gas. These changes consisted in adjusting the engines of the main drive so that they can be fuelled by gas. This has been achieved by the modification of the cylinder head and fuel supply installation. Parameter results of the modified engines obtained during sea trials have been presented. Both advantages and disadvantages resulting from gas combustion have been pointed out. Ultimately, the authors of this article assess the applicability of this solution to other LNG carriers.

Open access

Sergiei German-Galkin, Dariusz Tarnapowicz and Valentin S. Tomasov

Abstract

One of the methods to improve the efficiency of the ship’s propulsion is the increase of efficiency in ship generators by using permanent magnet synchronous generators (PMSG – Permanent Magnet Synchronous Generator). Due to the lack of voltage regulator in PMSG, it is necessary to use power electronic converters to maintain a constant voltage level. One of the modes of operation for a ship’s power plant is a parallel work of generating sets. In the parallel work, there are problems in the fluctuation of active and reactive electrical power between generators. The article presents the concept of using inverters in the IHBI topology, which enables the parallel operation of generating sets with PMSG generators. This solution enables the adjustment of the flow of active and reactive powers between generating sets.

Open access

Piotr Kaminski

Abstract

The frequent causes of ships’ detentions by port authorities are abnormalities of marine power plant functioning. Each extended ship lay time in port results in a waste of ship operating time thus costs rise to ship owners. This is connected with improper marine power plant management. In order to avoid this, a ship engineer should have at his disposal computer aided system supporting him in the managing of the marine power plant. One element of the decision making process in managing the marine engine room is to determine how important is each of the tasks which the operators have to do. This estimation is the base to choose the most important tasks and make optimal schedule with them using AHP method. Based on practice, a hierarchic structure of factors influencing a tasks validity in the engine room operating process was made. Next a preliminary questionnaire was conducted, which put questions to the experts as chief engineers next. This enabled to define numerical values of suitable coefficients influencing on the validity of operating tasks, show results of calculations in form of mileage parameters of engine as a function of crank angle.

Open access

Artur Bogdanowicz, Tomasz Kniaziewicz and Marcin Zacharewicz

Abstract

The paper describes the application of the author’s mathematical model of gas-dynamic processes for a marine piston engine based on a computer program. The developed mathematical and numerical model is designed to conduct simulation diagnostics. Therefore, it is possible to carry out calculations for motors in different technical conditions and observing influence of changes in technical condition on selected parameters of its work. Simulation of changes in technical condition is carried out by modifying parameters of structure’s model object. The article contains a detailed description of each options of the computer program. From the main program window, user can select type of engine model (supercharging method, cylinder number, work order, stroke and piston diameter and a number of other parameters). Through a window of simulation of known and recognizable damages such as: change in fuel dose for each cylinder, change in intake and outlet valves, leakage of piston-ring-cylinder system, change of injector hole cross section. Final windows show results of calculations in form of mileage parameters of engine as a function of crank angle.

Open access

Miloš Poliak, Patrícia Šimurková, Marek Jaśkiewicz and Salvador Hernandez

Abstract

The paper deals with the issue of different market access for the transport procurement in the EU in context of open market of providing forwarding services. It highlights different requirements of market access in freight forwarding. The article proposes conditions of market access unification in freight forwarding based on analysis of the existing situation. It also refers to the different responsibility of freight forwarder depending on membership in the national associations of freight forwarders. The contribution analyses the limitation of liability in freight forwarding and shows differences in contract of freight forwarding for particular shipments by model examples. There is also pointed to the need for the development of uniform freight forwarding conditions in the EU.

Open access

Rafał Jurecki and Miloš Poliak

Abstract

The article presents an analysis of traffic safety on major communication routes in Poland. The total number of accidents in Poland has been compared and analysed in relation to the objectives in the context of the GAMBIT programs and the National Road Safety Program for the years 2013-2020. Analyses of the number of accidents in the years 2004-2017 have been presented in the article. A significant decrease in accidents has been demonstrated and annual changes determined, the value of which ranged from 12.15 to 6.74%. The statistics on fatalities have been also analysed. A midyear change in the number of fatalities has been determined, which constitute -4.4% in the analysed period. The data on the number of vehicles registered in Poland, which considerably affects traffic congestion, has been presented. In spite of this, there has been no increase in the number of accidents. The work compares changes in the length of the most important types of routes in Poland, as well as accidents and fatalities that occurred on them. With the decreasing overall number of accidents in Poland, there has been a noticeable drop in accidents per 100 km of road length also on these roads. The fatality rate per 100 accidents in Poland has been determined and the average value of this rate in 2017 was 8.64, while on the analysed roads it ranged from 12.3 to 14.6.

Open access

Wiktor Filipek and Krzysztof Broda

Abstract

The interest in sea mining has resulted in the recent years in the creation of many new methods for the exploitation of marine deposits as well as the transport from the seabed to the. For several years, the authors have been trying to develop new concepts of transport from the seabed. In previous publications, the authors presented the concept of an autonomous transport module for transport from the seabed. The research so far has focused on the development of the module’s operation principles, determination of the energy source in the transport process and changes in the average density of the transport module. In this publication, the authors focused on the stability problem of the transport module during deployment and ascent. This is a very important issue, because the stability of the module will determine its practical suitability for transport from the seabed.

Open access

Wiktor Filipek and Krzysztof Broda

Abstract

In recent years, we have observed a great interest in the exploitation of marine deposits by various methods of mining and transport to the surface. However, obtaining natural resources deposited at greater depths such as polymetallic nodules and seafloor massive sulphides – SMS creates a lot of challenges for both scientists and engineers. The solutions developed so far, unfortunately, have so far been characterized by high energy consumption.

For several years the authors have been conducting theoretical and experimental research on new concepts of seabed to surface transport. The results of them have been presented in previous publications. This publication presents the results of the continuation of research on the concept of construction and operation of an autonomous transport module (submitted for printing). It focuses on a theoretical analysis of the change in gas phase density in the processes occurring during operation of the transport module intended for transport from the seabed. For this purpose, a reduced form of the van der Waals equation was used in the form of a third-degree equation for parameters interested from the point of view of the transport module.

Open access

Andrzej Jakubowski and Stanislau Dounar

Abstract

Original experimental technical equipment for making samples in the form of permeable tubes of porous material, i.e. coiled wire. The article describes the construction of the equipment, the processes of forming and pressing the wire semi-product and methods of fixing the ends of the wire product.

Open access

Anna E. Wolnowska, Aleksandra Szabrońska, Zbigniew Matuszak and Ondrej Stopka

Abstract

The purpose of the underlying paper is to highlight the significance of specialist and diploma-related apprenticeships at the bachelor degree studies provided by the technical university. The evaluation of the quality of apprenticeships was conducted among the students of the Economy, Engineering and Transport Faculty of the Maritime University of Szczecin (Poland), for the study directions Production Management and Engineering (Polish: ZiP), Logistics (L) and Transport (T). The research methodology was based on questionnaire form, statistical analysis of results reliability and the analysis of literature. The results of the conducted research unequivocally indicated a need to introduce changes to the organisation of the apprenticeships, as this area determines the quality of engineers practical education and influences their professional competences.