Naval Architecture

In previous research works an intact stability criterion has been developing aiming at determination of the sufficient intact stability of a vessel in a heavy weather condition. The aim of that criterion was the establishing of the minimum stability level that would ensure that the risk of capsizing that remains is as low as it is reasonably practical. Subject criterion results in the calculation of the index value.

To make this criterion applicable from the practice point of view we will need to define the threshold values for this index in order to distinguish between unsafe and safe vessels/conditions and establishing the minimum safety level in heavy weather. To set the threshold value for ISEI, standing for the insufficient stability event index), the authors of this volume have conducted the investigation of several events of the full-scale capsizing together with the numerical computational methods and procedures.

Subject procedures and methods are mainly based on the computation of non-linear rolling motions of the vessel. Such methods/procedures have been under development in the course of the last decades with the intention of their authors to conduct the analysis of the full scope events of capsizing for authorities of Germany. The associated computations could be used to determine the required threshold values for the dynamic intact stability criterion...

The whole process of design and further operation of the commercial vessels have been subjected to the significant changes during past decades. All of those changes together with the serious impact they have on the intact stability performance of vessels, have motivated the specialists of the IMO to develop the second generation criteria of intact stability. Among the most important modes of stability failure, considered primary, we would note the pure loss of ship stability, broaching-to and parametric roll resistance.

The stability criteria addressed in this publication have been designed in a multi-layered structure, with the first two layers consisting of level 1/2 vulnerability criteria mainly used for the preliminary checks of the risk of dynamic stability failure during the design stage. The present document describes the valuable contribution of the US specialists to the development of those criteria including all stability failure modes. Sufficient level of the intact stability of the vessel is the most basic and important requirement.

The working group dealing with the development of the second generation criteria for the intact stability of ships, has outlines three major modes of stability failures. One of the modes is the stability of the vessel under dead-ship conditions, as defined bi the corresponding SOLAS regulation contained in II-1/3-8. The other two modes cover the restoring arm variation and maneuvering related problems...

The ship survivability is directly related to the requirements governing the intact/damage stability of the ship. It should actually be noted that the intact survivability of the vessels has received relatively more attention. The safety of the passenger ships has always been considered a prime concern for all regulatory authorities. There are several established and proven ways of assessment of the damage stability of the ships, including the probabilistic, deterministic methods and the real-time simulation.

The main purpose of the present study was to address the further development of the ship stability software using the MATLAB program on the basis of the real time simulation, i.e. third approach, of the dynamic behavior of the damaged ship at waves. The particular vessel called "Sarawak Fast Ferry" has been specifically chosen to perform the parametric study for the further application of the DSP, standing for the Damage Stability Program, which, in turn, has been developed and introduced.

The experiment has been conducted by means of the image processing and the results obtained during the experiment showed a remarkably good correlation to the simulation results. Subject results have also shown that the loading conditions and height of the waves are the most important and influencing factor to the stability of the vessels...

Naval officers having some basic mathematical ability can easily make themselves familiar with the fundamental principles governing the design of the vessels and the most commonly used calculation methods; however, those willing to become naval constructors would require long and very patient apprenticeship of the shipyard.

The naval architecture addresses such the problems as how to make a vessel sail and carry weights, how to make the vessel stand right at sea and obey the commander, and go easily through the waves at a given speed, in fact everything connected with the construction of the vessels and prediction/calculation of their behavior at sea.

In fact, shipbuilding itself implies giving the materials of which the vessel is to be made of all the shapes, forms and dimensions, as well as strength and power characteristics required to make them fully comply with the conditions that have been already calculated by the naval architects. he naval architects, shipbuilders and marine engineers are representing three professional skills.

Their duties shall be performed successfully so that the duties of the newly built vessel may also be performed in a successful manner. All of these duties are considered essential but they do not have to be performed by three separate people... Have a look into this rare and classic book, you will not get disappointed, it is much more than a regular textbook.

As implied in the title of this booklet, it is dedicated to the stability of the fishing vessels. The stability of subject vessels is something people commonly depend on for both their lives and livelihood. Their actions and decisions they make is what keeps their ships safe. It shall be noted as necessary that even it is a very safe vessel complying with all requirements of the applicable rules, the wrong and poor decisions related to the operation can easily result in the loss of stability and even capsizing of the vessel.

The present guide is intended to help the crew members of the fishing vessels and all people sailing on them or involved in their design and construction properly understand the most important elements directly influencing the stability of the fishing vessels as well as the critically important hazards that subject vessels are commonly exposed to. Understanding all factors reducing stability of the vessels will help people in making right decisions and taking right actions to keep their vessels safe.

The main content of the booklet has been arranged in two big sections. While the first section of the title describes the whole importance of stability covering its basics, acting forces and characteristics, the second section has been fully dedicated to the stability hazards that the readers shall look out for, such as the downflooding, overloading, water ingress, and preventive measures...

One of the main objectives of the present document is to develop a fast and stable plus reasonably accurate method of numerical simulation in order to revisit and predict the flooding scenarios. The author, Henrin Dankowski, has performed a good professional comparison with the results obtained in the course of the standard benchmark tests and repeated investigation of three accidents, namely the Estonia, the Heraklion and the European Gateway, for validation purpose.

The aim of the method presented in this volume was to fill the gap that exists there between relatively simple evaluations of ship stability and more complex and time consuming methods of simulation of the seakeeping. Subject method has been implemented in the software environment E4 specifically developed for ship design. Subject environment is providing users with the direct access to the complete vessel data model and to the computational algorithms that have already been implemented.

Calculations of the damage stability of a vessel at early stages of the design are considered essential indication of the vessel's safety level to withstanding the water ingress. Several accidents that have occurred in the past are demonstrating how important it is to consider the intermediate stages of flooding process and not only looking at the resulting final stage.