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During the design of the ship the most important decisions are made at the stage of preliminary design. One of the most important design parameters assumed by the shipowner is its service speed in real weather conditions occurring in the shipping line. For this speed, at the stage of preliminary design, when are known only to the basic geometric parameters of the ship should be determined motor power. In practice design, power propulsion is determined with a very approximate formulas but for the speed in calm water. Only after the project contract and the signing of the contract are carried out by means of resistance and self-propulsion of model test. The paper presents a mathematical model for determining the power propulsion for the assumed operating speed. This model is dependent only on the basic geometric parameters of the hull of the ship and the weather parameters occurring in liner shipping. Also shows the results of calculations according to this model, the power propulsion for one of vessels built.

The study is aimed at designing a system which ensures dock mobility (moving from the quay to the dock trench) and stabilises the dock in position during docking operations. A number of requirements and design criteria have been defined for the dock moving system, the most important of them being its capability to support docking operations at a maximum wind force of 5 °B, and environmental friendliness (zero exhaust fumes or other pollutants). As part of the research, concepts for various dock moving systems have been developed, including calculations of technical and operational parameters. Each concept has been analysed for meeting the defined requirements and design criteria. Ultimately, a system which meets all of the requirements and criteria and is completely environmentally friendly has been selected for construction. The authors discuss the entire process of creating system concepts, parameter calculations, and assessment of fulfilment of the requirements and design criteria. The principle of operation and the design of the system have been explained. The dock is powered by electricity stored in batteries and generated from renewable energy sources. [ABSTRACT FROM AUTHOR]

During the design of the ship the most important decisions are made at the stage of preliminary design. One of the most important design parameters assumed by the shipowner is its service speed in real weather conditions occurring in the shipping line. For this speed, at the stage of preliminary design, when are known only to the basic geometric parameters of the ship and its motor power should be determined. In practice, design, power propulsion is determined with a very approximate formulas but for the speed in calm water. Only after the project contract and the signing of the contract are carried out by means of resistance and self-propulsion of model test. The article presents the concept of the method for determining the power propulsion for the assumed service speed, which depends only on the basic geometric parameters of the ship’s hull.

Optimising the ship route is one of the most important tasks related to the operation of the vessel, its safety, and economic aspects of transport. Nevertheless, from a mathematical point of view, this problem has not been solved yet sufciently precisely due to very high complexity of the model to be used to describe the motion of the ship along the shipping line, and time- and space-dependent average values of statistical weather parameters recorded during ship sailing. Tat is why various approximate methods are used, which, among other procedures, utilize ship speed characteristics, having the form of very simple relations between basic dimensions of the ship and the expected speed decrease at the assumed weather parameters. Te paper presents a new method of calculating the speed decrease depending on technical and operating parameters of a given vessel. A computer code prepared based on this method is used for research on forecasting ship speed in real weather conditions.

Environmental protection is one of the most challenging tasks facing mankind. Reducing CO2 emissions in the global economy, including maritime transport, is being pursued in various ways, one of them being the design work leading to the construction and operation of unmanned ships. Unmanned vessels operating on longer routes will still have internal combustion propulsion. However, they will not have the superstructure and the various systems and equipment necessary for the crew. This will result in an unmanned vessel having less weight, less displacement and, therefore, less size, resistance and propulsion power than a manned vessel for the same transport capacity. Consequently, the unmanned vessel will emit less CO2. This paper presents a novel method for predicting fuel consumption and CO2 emissions for unmanned container ships. The method uses regression relationships of geometric and operational parameters for manned container ships developed for this purpose to determine such relationships for unmanned ships. On this basis, it is shown what the level of CO2 reduction will be compared to manned container ships. [ABSTRACT FROM AUTHOR]

Unmanned, remotely or autonomously ships are the fastest growing new technology in maritime transport in recent years. The design of unmanned vessels envisions clean, emission-free electric propulsion. The costs of building physical models and target vessels are high, but the expected benefits are generating increasing interest in such vessels. This article presents the current state of research in the field of unmanned ships and the technical, legal and administrative problems that need to be solved in order for these ships to be used by the general public. [ABSTRACT FROM AUTHOR]

In this paper, an experimental model has been developed to study an unmanned ship. Two aft azimuthal propellers and two bow tunnel thrusters were used to propel the ship. In order to develop algorithms and a computer program to control the model, it is necessary to determine the hydrodynamic characteristics of the propellers installed in the model. The propellers are very small; therefore it is impossible to use approximate methods of calculating the thrust of the ship's propellers. The characteristics of the thrust of the propellers installed in the model were measured experimentally. This paper has given a description of the test stand and the results of the measurement of the thrust forces of the propellers installed in the model of an unmanned ship. [ABSTRACT FROM AUTHOR]

The article presents regression formulas for calculating the friction resistance RF and the total resistance RT of ship models in the 2.0-10.0 m range. The method for calculating the total resistance is novel and applies to the design models of an unmanned surface vessel (USV) for experimental testing of autonomous control. For both regression models (RF and RT), statistical and substantive tests were performed (the results of the calculations were compared with the experimental measurements). In both cases, convincing results were obtained, which have confirmed the possibility of their use at the preliminary design stage of unmanned ship models. [ABSTRACT FROM AUTHOR]

As part of this research, an experimental model of an unmanned ship equipped with an ecological electric drive was built. Ultimately, the ship model was equipped with an on-board computer with appropriate software for autonomous control. A computer simulator was used to test the control software. This article presents the concept of such a simulator, a general mathematical model of the movement dynamics of an unmanned vehicle, a description of the propulsion system, and the tasks planned for implementation in a computer simulator. [ABSTRACT FROM AUTHOR]

One of the methods of collecting polymetallic nodules from the sea floor is a hydraulic system using a single or double vertical pipeline. While mining, collecting pipelines suspended from a mining support vessel (MSV) move together. As a result of both the MSV's motion with a suspended pipe system and water action (including deep-water currents) a vertical deflection and deformation occur along the pipeline. Simultaneously, stretching and bending tensions emerge along the pipeline. The article presents computer simulation results of vertical deflection and tensions within single and double vertical pipelines with fixed force from the ship's movement (linear movement at constant speed) and regular force from the waves. [ABSTRACT FROM AUTHOR]

Ocean mining systems that incorporate a single or double lift pipe are two methods used to obtain polimetallic nodules from the seabed. The pipe must be equipped with main cables and flexible pipe attached to the mining vehicle collecting nodules. While mining, the pipes in the vertical configuration are moving along with the ship above. They are subjected to currents in the water column. Such current-induced hydrodynamic drag results in a vertical deflection, which is dependent - among other factors such as varying current velocity at points along the length of the pipe. The present paper presents results of computer simulations using commercial CFD software to model the hydrodynamic forces acting on the vertical pipe of ocean mining systems. The results present the influence of the water flow direction in relation to the lift pipe on the hydrodynamic force and torsional moment acting upon the pipe. [ABSTRACT FROM AUTHOR]

When designing a transport vessel, one of the most important parameters assumed by the owner is the service speed of the ship. Service speed and motor power are calculated as an approximation of the ship's speed in calm water (i.e., the contract speed) with the addition of the sea margin (SM). In current design practice, the addition of SM is not dependent on weather parameters occurring in liner shipping. This paper proposes a new method for establishing the value of SM depending on the type and size of the vessel and the average statistical weather parameters occurring on various shipping lines. The results presented in this paper clearly demonstrate that further research is needed to determine the precise relationship between the shipping and vessel type and the weather parameters on a shipping line. [ABSTRACT FROM AUTHOR]

During ship design, its service speed is one of the crucial parameters that determine its future operational profitability. As sufficiently exact calculation methods applicable to preliminary design stage are lacking, the so-called contract speed, the speed a ship reaches in calm water, is usually specified during the draft stage. The service speed obtainable by a ship under real weather conditions (mainly wind and waves) is one of the most important parameters influencing a ship's profitability on a given shipping route. This paper presents a parametric model of calculating total ship resistance on a given shipping route under actual weather conditions (wind, waves, sea current), that could be useful in the initial design of container ships. [ABSTRACT FROM AUTHOR]

During ship design, service speed is one of the crucial parameters in determining the operational economy of the vessel. As sufficiently exact calculation methods applicable to preliminary design stage are lacking, the so-called contract speed, the speed which a ship reaches in calm water, is usually cited. Żelazny (2015) developed a parametric method for calculating total ship resistance under actual weather conditions (wind, waves, sea current). This paper presents a parametric model of a ship's propulsion system (screw propeller -- propulsion engine) as well as a method, based on both the resistance and propulsion system models, of calculating the mean statistical value of a ship's service speed under the seasonal weather conditions occurring on shipping lines. The method makes use only of basic design parameters, and may be applied in preliminary design phase of container ships. [ABSTRACT FROM AUTHOR]

To forecast the optimum route passage of a vessel in the real weather conditions using the so-called velocity characteristics of the ship. These are developed in the way, as to have a very simple form, which can not guarantee high precision in calculating the speed of the vessel. The paper presents a mathematical model of the external forces operating in the vessel and the algorithm to solve this model for calculating the instantaneous speed of the vessel in the selected weather conditions. Made of a computer program, after appropriate research and testing, can be used to optimize the transport route of the ship. [ABSTRACT FROM AUTHOR]

While the ship is sailing on waves the relative motions occur which result in propeller emergence, and as a consequence -- propeller thrust reduction which results in a decrease in the ship's speed. Propeller emergence is also accompanied by the decrease in torque values, with which the propeller affects the propelling engine. The article presents both calculation results and the algorithm for calculating the decrease in torque of the propeller during ship motion on a regular wave. [ABSTRACT FROM AUTHOR]

When a ship is sailing on waves the relative motions occur which result in propeller emergence, and as a consequence -- propeller thrust reduction which results in a decrease in the ship's speed. Propeller emergence is also accompanied by the decrease in torque values, with which the propeller affects the marine engine. The article presents both calculation results and the algorithm for calculating the decrease in torque of the propeller during ship motions on irregular wave. [ABSTRACT FROM AUTHOR]