Upscaling Float-over Installation

This paper presents the latest developments in Transport and Installation methods for Topsides up to 38,500mt. For such heavy-weight structures Boskalis introduces a solution by combining the beneficial features of a Heavy Transport Vessel dry-transportation with the advantages of a DP2 Barge float-over installation. This unique Transport and Installation approach, a so called "Piggyback T&I", may be characterized as follows:

Selection of the composition and parameters of the propulsive complex of increased speed sea transport vessel

В работе предложена методика выбора состава и основных параметров двигательно-движительного комплекса морского транспортного судна, предложены критерии оценки указанного выбора. С использованием этой методики решена задача выбора числа гребных валов при проектировании транспортных судов повышенной скорости хода. Задача решена применительно к судну RO-RO типа «Сергей Киров» (проектная скорость 17 узлов) и контейнеровозу ФЕСКО «Байкал» (проектная скорость 22 узла). В качестве критериев оценки проектных решений использована совокупность величин: пропульсивный коэффициент, часовой расход топлива в главных двигателях и суммарные затраты денежных средств на покупку и эксплуатацию главных двигателей в течение расчётного срока. Второй из перечисленных критериев использован в составе относительного конструктивного коэффициента энергетической эффективности (EEDI), который по сути является величиной, характеризующей уровень выброса СО2 в атмосферу. В работе использован авторский программный комплекс ENGINES автоматизированного проектирования судового пропульсивного комплекса. В программе предусмотрен расчёт ходкости суда, параметров гребного винта, а также выбор из электронного каталога вариантов главного двигателя. Для каждого двигателя выполнена совместная оптимизация параметров гребного винта и рабочей точки двигателя с целью обеспечения минимального часового расхода топлива. Расчёты показали, что граничная проектная скорость движения судна, при превышении которой целесообразен переход от одновальной установки в двухвальной, составляет: для RO-RO – 16 узлов; для контейнеровоза – 25 узлов. The paper proposes a method for selecting the composition and main parameters of the propulsive complex of a marine transport vessel, and suggests criteria for evaluating this choice. Using this technique, the problem of selecting the number of propeller shafts in the design of increased speed transport vessels is solved. The problem is solved in relation to the RO-RO vessel "Sergey Kirov" (design speed 17 knots) and the container ship FESCO "Baikal" (design speed 22 knots). As criteria for evaluating design solutions, a set of values is used: the propulsive coefficient, the hourly fuel consumption in the main engines and the total cost of funds for the purchase and operation of the main engines during the estimated period. The second of these criteria is used as variety of the relative constructive energy efficiency coefficient (EEDI), which is essentially a value that characterizes the level of CO2 emissions into the atmosphere. The paper uses the author's software package ENGINES for computer-aided design of the ship's propulsive complex. The program provides for the calculation of the ship's seaworthiness, the parameters of the propeller, as well as the selection of the main engine from the electronic catalog of options. For each engine, the parameters of the propeller and the operating point of the engine are jointly optimized to ensure a minimum hourly fuel consumption. Calculations have shown that the limit design speed of the vessel, when exceeding which it is advisable to switch from a single-shaft installation to a two-shaft one, is: for RO-RO – 16 knots; for a container ship - 25 knots.

Resistance Tests of an Articulated Pusher Barge System in Deep and Shallow Water

Articulated pusher barge vessel is a short-distance transport vessel with good economic performance and practicability, which is widely used in the Yangtze River of China. In this present work, the resistance performance of articulated pusher barge vessel in deep water and shallow water was studied by model tests in the towing tank and basin of Shanghai Ship and Shipping Research Institute. During the experimental investigation, the articulated pusher barge vessel was divided into three parts: the pusher, the barge and the articulated pusher barge system. Firstly, the deep water resistance performance of the articulated pusher barge system, barge and the pusher at design draught T was studied, then the water depth h was adjusted, and the shallow water resistance at h/T = 2.0, 1.5 and 1.2 was tested and studied respectively, and the difference between deep water resistance and shallow water resistance at design draught were compared. The results of model tests and analysis show that: 1) in the study of deep water resistance, the total resistance of the barge was larger than that of the articulated pusher barge system. 2) for the barge, the shallow water resistance increases about 0.4–0.7 times at h/T = 2.0, 0.5–1.1 times at h/T = 1.5, and 0.7–2.3 times at h/T = 1.2. 3) for the pusher, the shallow water resistance increases about 1.0–0.4 times at h/T = 2.7, 1.2–0.9 times at h/T = 2.0, and 1.7–2.4 times at h/T = 1.6. 4) for the articulated pusher barge system, the shallow water resistance increases about 0.2–0.3 times at h/T = 2.0, 0.5–1.3 times at h/T = 1.5, and 1.0–3.5 times at h/T = 1.2. Furthermore, the water depth Froude number Frh in shallow water was compared with the changing trend of resistance in shallow water.

Application of Measurement Sensors and Navigation Devices in Experimental Research of the Computer System for the Control of an Unmanned Ship Model

Unmanned autonomous transport vessels (MASS) are the future of maritime transport. The most important task in the design and construction of unmanned ships is to develop algorithms and a computer program for autonomous control. In order for such a computer program to properly control the ship (realizing various functions), the ship must be equipped with a computer system as well as measurement sensors and navigation devices, from which the recorded parameters are processed and used for autonomous control of the ship. Within the framework of conducted research on autonomous ships, an experimental model of an unmanned ship was built. This model was equipped with a propulsion system not commonly used on transport vessels (two azimuth stern thrusters and two bow tunnel thrusters), but providing excellent propulsion and steering characteristics. A complete computer system with the necessary measuring sensors and navigation devices has also been installed in the model of the ship, which enables it to perform all functions during autonomous control. The objective of the current research was to design and build a prototype computer system with the necessary measurement sensors and navigation devices with which to autonomously control the unmanned ship model. The designed computer system is expected to be optimal for planned tasks during control software tests. Tests carried out on open waters confirmed the correctness of the operation of the computer system and the entire measurement and navigation equipment of the built model of the unmanned transport vessel.

«PRIORITY IN THE CREATION OF AN ACTIVE ICEBREAKING AND HEAVY-DUTY TRANSPORT VESSEL SHALL BE RETAINED BY THE SOVIET UNION»

The beginning of the 1950s was a period of active exploration of the Northern Sea Route, as well a time of aggravation of relations between world powers, which led to the development and strengthening of new economic and political positions of the Soviet Union. The authors of the article describe the prerequisites and the development of icebreaking shipbuilding in the USSR in the face of significant demand for new ships with a principled position to leave the accumulated experience inside the country. Particular attention is paid to an in-depth analysis of the established situation and the practice of developing a new icebreaking vessel at that time by outstanding Leningrad scientists from the Chief Directorate of the Northern Sea Route under the Council of Ministers of the USSR: A.I. Brandaus, V.F. Burkhanov, V.I. Neganov, N.A. Eremeev, A.S. Kolesnichenko, M.Y. Rogov and others. The paper also reflects the great interest of the central organizations of shipbuilding and management of the sea and river fleet in the rapid advancement of this project in the USSR.

Aspects of investment risks assessment in transport vessels modernization

The article presents a descriptive account of economic feasibility of obsolete transport vessels continuing operation by assessing the investment risks on their modernization efforts. The issues of economic assessment of the shipowner's investment risks when making a management decision on the transport fleet modernization are considered. The algorithm of management of the ship modernization risks is defined. The stages of the risk management of vessel modernization are analyzed and listed: risk identification, risk analysis, risk assessment, risk control. Formal foreign systems of risk classification, their content and differences are analyzed. A classification of transport vessel modernization risks has been developed, which allows identifying and structuring information about ship modernization risks and differentiating them by main classification criteria. The discount rate for the transport vessel modernization investment project based on risk premiums has been determined. According to this method, the discount rate is calculated as the sum of the risk-free interest rate, the rate of inflation, and the risk premium that was calculated by an expert method for the modernization project of a mixed-use dry cargo vessel. A quantitative assessment of the modernization risks of a mixed-navigation dry cargo vessel has been performed, the most significant classification features have been identified (modernization risk and industry risk). The currently topical natural risk of coronavirus infection has also been stated.

ОХОЛОДЖЕННЯ НАДДУВНОГО ПОВІТРЯ ГОЛОВНОГО СУДНОВОГО ДВИГУНА ЕЖЕКТОРНОЮ ХОЛОДИЛЬНОЮ МАШИНОЮ В ЕКВАТОРІАЛЬНИХ ШИРОТАХ

The efficiency of cooling the scavenge air of the main low-speed engine of the transport vessel during operation in the equatorial tropical latitudes is analyzed. The peculiarity of the tropical climate is the high relative humidity of the air at the same time its high temperatures and temperatures of seawater. The cooling of the s scavenge air with a refrigerant ejector chiller was investigated by transforming the scavenge air heat into the cold. With this, the potentially possible minimum temperature of the cooled air was determined considering the boiling temperature of the refrigerant and the temperature differences in the heat exchangers of the intermediate water cooling circuit. Refrigerant ejector chiller is used as the most simple and reliable in design. However, the efficiency of converting the heat to cold by ejector chillers is low: their coefficients of performance are approximately 0.3. Circuit-design solution of three-stage cooling system of scavenging air of ship's main engine - in high-temperature (cogeneration) stage using the extracted heat of scavenging air to get cold with ejector chiller and traditional stage for cooling scavenge air by seawater and low-temperature cooling stage by ejector chiller. The effect of deeper cooling of the scavenge air was determined in comparison with the cooling of the scavenge air with seawater, taking into account the changing climatic conditions during the route of the vessel. It is shown that because of the insufficiently high efficiency of transformation of the scavenge air heat by the ejector chiller (low coefficients of performance) the obtained cooling capacity is not sufficient to cool the scavenge air to a potentially possible minimum temperature of 22 °C when operating the ship engine in tropical climates. However, the heat deficit is relatively small and can be covered by the use of additional exhaust gas heat.