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Information about the adoption of CIFT fishing boat designs was collected from 54 boat building yards of the country. The majority of the boats were built as per CIFT designs. The types of wood used and the designs were dependent upon each other. Other variables studied did not show significant effects upon the type of adoption. The CIFT designs were modified at some yards and these details are discussed.

The paper will be concerned with the problem of generating curves (and surfaces) interactively from given form parameters (offsets, derivatives, area, centroid, etc.) and applying the result to practical surface design problems. The first part of the paper describes the basic methods and the second part deals with the practical application of the methods to ship design.

This report presents a summary of the design philosophy for an ice capable longliner, including detailed designs for one such vessel, to be represented by IMD model 404.

The mathematical definition and fairing of hull lines presents several advantages as: a) Speed-up of the hydrostatic calculations, which are possible since the preliminary phases of hull definition; b) Easy change of main dimensions and local/global shape with immediate evaluation of the modifications in the points relevant for stability and hydrodynamic evaluation. c) Automatization of the production process through the codes for nesting and numerical control of cutting/welding machines. After fifteen years of industrial applications the practical results are, however, not yet satisfactory. In this paper the authors present a new methodological approach based on the definition of hull surface by means of the so-called longitudinal control lines.

The VAX/VMS UIS graphics library routines were used in the creation of a menu driven, interactive program which solves basic preliminary ship design problems. The program uses a menu with active mouse and keyboard to select options, enter data, and control program execution. At present, the program solves transverse and longitudinal static stability problems and predicts the effects of shifting weight in three planes. It also calculates the hydrodynamic derivatives for maneuvering performance and predicts the turning circle characteristics of the ship. Provisions for a hardcopy, detailed report are also included. Space has been allocated to include future program modules or user supplied programs. http://archive.org/details/applicationofvax1094527529 Lieutenant, United States Navy Approved for public release; distribution is unlimited.

Collision detection between several objects in a closed space is of fundamental importance in all those areas where objects must not penetrate one another, such as computer grafics, robotics, motion planning, computer animation, virtual reality, etc. The problem to detect collisions in very complex systems has been studied by several authors, obtaining solutions based on different data structures. In this paper, a new K dimensional tree Multiresolution Kdtree, MKtree is introduced. The MKtree represents a hierarchical subdivision of the scene objects that guarantees a minimum space overlap between node regions. MKtrees are useful for collision detection and for time--critical rendering in very large environments requiring external memory storage. Examples in ship design applications are described.

Offshore wind farms play a decisive role in the exit from fossil-fuel energy in Germany. These offshore wind turbines are oftentimes installed with jack-up vessels. At the site of operation these vessels lift their hull above the water surface by extending their jacking legs. The vessel’s seaway-induced motions at the moment of initial contact between leg and seabed define the critical dynamic structural loads onto the legs and the jacking mechanism, which have to be minimised. Therefore, an analysis of the seakeeping behaviour during the sensitive jacking sequence is required in the early design stage in order to define the vessel’s operational limits of sea state. The ship design environment E4 is an open software framework, being developed by the Institute of Ship Design and Ship Safety, which provides various methods for the dynamic analysis of a digital twin of the actual ship. However, these methods are restricted to conventional ship-type structures whereas the analysis of the seakeeping behaviour during the jack-up process further requires a consideration of the jacking legs’ hydrodynamic influence. For a holistic analysis of the seakeeping behaviour, the forces onto the legs were thus accounted for by a Morison approach in the calculation of the required response amplitude operators. This paper presents the calculation of the vessel’s seakeeping behaviour in irregular waves in time domain on the basis of these modified RAOs. The applied method calculates the vessel’s response motions in six degrees of freedom. Since the roll motion tends to show the largest response amplitudes in a seaway this degree of freedom is calculated in a non-linear way with respect to the wave amplitude and the roll angle by solving its equation of motion. The motions in the residual degrees of freedom are calculated from the underlying linear response amplitude operators. The achieved results are validated by model tests of a jack-up vessel with extended legs in irregular long-crested waves. This extended method represents a quick computational tool for early design applications in order to determine limiting sea states for the jacking sequence, which is a major design aspect of such ships.

En el presente proyecto, se realiza el diseño preliminar de una embarcación de navegación interior cuyo propósito es el de dar servicio de restaurante a bordo a 100 pasajeros. Mediante este diseño, se pretende profundizar en un campo poco común y proporcionar un ejemplo de diseño de una embarcación de pasaje que podrá servir como guía y ejemplo en futuros estudios sobre el tema. Para llevar a cabo el diseño del buque, se ha propuesto que esté destinado a navegar en el río Duero portugués. Se ha aplicado esta información al diseño, para mejorar la precisión y dotar de realismo al proyecto. La metodología utilizada en el presente estudio se basa en la llamada espiral de diseño. En el caso del presente proyecto, se realiza la primera vuelta o ciclo a la espiral, el llamado diseño conceptual o preliminar. En él se establece una base con las principales características del diseño. En este proyecto se realizará el estudio de los capítulos de dimensionamiento, diseño de la carena, dimensionamiento de la planta propulsora, disposición general del buque y cálculo de pesos y análisis de la estabilidad. Al finalizar el proyecto se valorarán los resultados obtenidos. Además, se expondrán posibles vías para la continuación del diseño en un futuro y una valoración personal sobre la realización del proyecto.

Die Schifffahrt verantwortet ca. 3 % der globalen CO2-Emissionen. Die IMO hat sich das Ziel gesetzt, diese bis 2030 um 40 % zu senken. Um dieses Ziel zu erreichen, müssen Effizienzgewinne erlangt und Möglichkeiten geschaffen werden, emissionsfreie Energiequellen möglichst einfach in das Schiffsenergiesystem zu integrieren. Ein Schlüsselelement ist die Umstellung der Bordnetze auf Gleichspannung (DC). In modernen AC-Schiffsnetzen sind zahlreiche Stromrichter zum effizienten Teillastbetrieb von Motoren verbaut. Alternative Energiequellen wie Brennstoffzellen, Batterien oder Photovoltaik basieren ebenfalls auf DC. Die Kopplung all dieser Komponenten in einem DC-Netz vermeidet die zahlreichen verlustbehafteten Wandlungen eines AC-Netzes. Um solch ein vermaschtes DC-Netz auf verschiedensten Schiffstypen zu integrieren, sind zahlreiche Fragestellungen zu untersuchen. Es wird ein Einblick in zwei Forschungsprojekte gegeben. Konzeptionelle Fragestellungen bzgl. Betriebsspannungen, Erdungs- und Schutzkonzepten, Parallelbetrieb von Umrichtern und Batterien, Lastflusssteuerung und Netzregelung sowie der Netzstruktur von Mittel- und Niederspannungsnetzen werden experimentell und simulativ untersucht. Um eine kostengünstige Anwendbarkeit auf vielen Schiffstypen zu ermöglichen, wird zur Berücksichtigung der unterschiedlichen Anforderungen eine Modularisierung des Energiesystems mit möglichst vielen Gleichteilen vorgenommen. Dabei werden regulatorische Rahmenbedingungen bereits in den Forschungsprojekten berücksichtigt und die Ausgestaltung des Energiesystems einer Gesamtsystemoptimierung unterworfen, die einen kostenoptimalen Betrieb und Aufbau des Energiesystems ermittelt., The shipping industry is responsible for approx. 3% of global CO2 emissions. The IMO has set a target to reduce them by 40% by 2030. Efficiency gains and options to easily integrate zero-emission energy sources into the ship’s energy system must be achieved to reach that goal. A key element is the conversion of on-board power systems to direct current (DC). Modern AC shipboard grids contain numerous power converters for efficient part-load operation of engines. Alternative energy sources such as fuel cells, batteries or photovoltaics are based on DC as well. Coupling all these components in a DC grid avoids the numerous conversion losses of an AC grid. To integrate such a meshed DC grid on a wide variety of ship types, numerous issues need to be investigated. An insight into two research projects is given. Conceptual questions concerning operating voltages, grounding and protection concepts, parallel operation of converters and batteries, power flow control and grid control as well as the grid structure of medium and low voltage grids are investigated experimentally and simulatively. To enable cost-effective applicability to many ship types, the power system is modularized with as many common parts as possible to account for different requirements. The regulatory framework is already being taken into account in the research project. The design of the energy system will be subject to an overall system optimization, which determines a cost-optimal operation and structure of the energy system.

This paper presents the concept of a fully electrified ferry that aims to support and promote energy efficient, zero GHG emission and air pollution, free waterborne transportation for island communities, coastal zones and inland waterways in Europe and beyond. Existing state-of-the-art ferries with 100% electric drive train systems are suffering from major limitations in range and are thus only being built and applied for very short ferry connections. The E-ferry, goes beyond this limitation targeting medium range connections and aims to become the ferry with the largest battery pack ever installed on a vessel. Other state-of-the-art solutions are based on retrofit, integrating hybrid or 100% electric systems in existing ferries suffering from lack of energy efficiency due to an existing energy inefficient vessel design. The E-ferry concept also differs from all other known projects by a record breaking high charging power of up to 4 MW allowing for short port stays. This is important for the operational profile of most ferry routes. Starting from a state of the art analysis on the use of alternative fuels in EU ferries, the paper presents the barriers that currently exist in Europe preventing the successful implementation of electrical ferries and how the proposed E-ferry aims to address them. It also reports on the competitive advantages of E-ferry in terms of cost efficiency, speed, trip frequency, capacity, dependability and overall environmental performance. Finally, the market penetration potential of this innovative ship is assessed.

Um den Anforderungen der deutschen Offshore-Windindustrie gerecht zu werden, besteht der Bedarf an individuell zu diesem Zweck entworfenen und gebauten Offshore-Windpark-Errichterschiffen. Eine der primären Entwurfsrandbedingungen dieser Schiffe ist das dynamische Positionieren (DP). Für die korrekte Dimensionierung von DP-Systemen sollten bereits im frühen Schiffsentwurf statische und dynamische Berechnungen durchgeführt werden. Zu diesem Zweck werden als Eingangsgrößen unter anderem Zeitreihen und zeitliche Mittelwerte der horizontalen Wellendriftkräfte und des Wellendriftgiermoments benötigt. Hierfür wird eine Berechnungsprozedur auf Basis der Streifenmethode in Kombination mit einer Korrektur für kurze Wellen vorgestellt und mit Versuchsergebnissen für den SIETAS TYP 187 validiert., In order to fulfill the requirements of the German offshore wind industry individually designed and constructed offshore wind farm installation vessels are needed. One of the primary design constraints of these ships is dynamic positioning (DP). For the correct design of DP systems static and dynamic calculations should already been performed during the early ship design. Among other input data time series and time averaged mean values of the horizontal wave drift forces as well as the wave drift yaw moment are needed. For this a calculation procedure based on strip theory in combination with a correction for short waves is presented and validated with experimental results for the SIETAS TYPE 187.

Collision detection between several objects in a closed space is an interesting research topic in all those areas where objects must not penetrate one another, such as Computer Graphics, Computer Vision, Virtual Reality. In this paper, we describe a new data structure design that is useful for collision detection in the environment of ship design applications and several algorithms that solve the collision problem in such environment. The paper is focused on collision detection in complex systems with a large number of objects.

Diese Arbeit beschreibt einen neu entwickelten Ansatz für die Bewertung und Optimierung von Schiffsentwürfen. Der in diesem Zusammenhang implementierte Simulationsalgorithmus verwendet die Monte Carlo Methode, um die Einsatzbedingungen während eines frei wählbaren Zeitraumes für ein projektiertes bzw. ein bereits im Dienst befindliches Schiff zu vorherzusagen bzw. zu reproduzieren. Auf der Grundlage von statistisch aufbereiteten schiffsspezifischen und umweltbedingten Daten in Kombination mit direkten Berechnungen der Propulsion ist es möglich, Schiffsentwürfe in Bezug auf verschiedene Parameter zu bewerten. Diese Parameter können sich sowohl auf den Schiffsentwurf an sich als auch auf dessen Betrieb beziehen. Durch Verwendung der Monte Carlo Methode wird eine ausreichende Anzahl von Betriebspunkten generiert. Diese Punkte beinhalten die Schiffsgeschwindigkeit, die Schwimmlage und die Umweltbedingungen (Wind und Seegang). Nachfolgend wird die Gleichgewichtsbedingung für den Propulsionspunkt unter Verwendung eines bereits verfügbaren und validierten Manövrieralgorithmus berechnet. Durch diese Methode ist es möglich, ein spezifisches Anforderungsprofil zu erstellen und den Schiffsentwurf bzw. das Operationsprofil (z.B. die Trimmverteilung) dahingehend abzustimmen. Die vergleichsweise geringen Rechenzeiten gestatten es, die Auswirkungen von parametrischen Entwurfsvariationen sowohl ökonomisch als auch ökologisch zu bemessen. Dieses Vorgehen kann an verschiedene Schiffstypen, Fahrtgebiete und damit eng verknüpft auch das jeweilige Frachtaufkommen angepasst und so direkt auf die individuellen Bedürfnisse zugeschnitten werden. Zum Zwecke der Validierung des entwickelten Simulationsalgorithmus sind die Ergebnisse mit Daten aus Langzeitmessungen von verschiedenen Schiffen unterschiedlichen Typs verglichen worden., This thesis describes a newly developed approach to ship design evaluation and optimisation. The therefore implemented simulation algorithm employs the Monte Carlo Method in order to reproduce and predict lifetime operation conditions of a projected (or existing) vessel. On basis of statistically analysed vessel-specific and environmental data in combination with direct calculations of the vessel’s propulsion it is possible to benchmark different designs regarding various parameters. These parameters can either be design-, but also operation-specific. Applying the Monte-Carlo-Method, the vessel’s speed, its floating condition and the environmental conditions (wind and sea state) are determined for a sufficient number of parameter sets. Subsequently the equilibrium condition for the propulsion point is computed, utilising an already implemented manoeuvring algorithm. Following this proceeding, it is possible to identify the specific requirement profile and to align the vessel’s design or the operating conditions (e.g. trim distribution) with this profile. Since this methodology computes rather fast, it offers the possibility to assess the impact of parametric design variations economically and ecologically. This assessment can be adjusted to different vessel types, shipping routes and connected to this the commodity flow, tailored to the individual needs. In order to validate the calculation method’s feasibility, the algorithm’s results have been checked against measured long-term data from various vessels of different type in operation.

Whereas shape optimal design has received considerable attention in many industrial contexts, the application of automatic optimization procedures to hydrodynamic ship design has not yet reached the same maturity. Nevertheless, numerical tools, combining together modern computational fluid dynamics and optimization methods, can aid in the ship design, enhancing the operational performances and reducing development and construction costs. This paper represents an attempt of applying a multidisciplinary design optimization (MDO) procedure to the enhancement of the performances of an existing ship. At the present stage the work involves modeling, development, and implementation of algorithms only for the hydrodynamic optimization. For a naval surface combatant, the David Taylor Model Basin (DTMB) model ship 5415, a three-objective functions optimization for a two-discipline design problem is devised and solved in the framework of the MDO approach. A simple decision maker is used to order the Pareto optimal solutions, and a gradient-based refinement is performed on the selected design.