Identifying and improving the internal and external information exchange for shipbuilding processes

To identify and improve the communication or information flow for a ship production process, this thesis provides an approach to use a Discrete Event Simulation (DES) model, based on Petri Net technique. By establishing a theoretical framework, the different simulation modelling options are analysed and based on practical requirements, a choice...

A Reference-based Design Approach: in Preliminary Ship Design

Design decisions which are made in the preliminary ship design phase have a significant influence on the performance and total cost of a ship. These design decisions are mostly made with very little knowledge of the ship design problem. In fact, it is the personal experience of the naval architect which plays a significant role in this phase of...

The effect of the yield to tensile strength ratio on the stress field in stress/strain concentrations around holes in steel structures

The aim of this thesis is to determine the influence of the Y/T, yield to tensile strength, ratio on the stress fields of high strength steels. This is relevant to the offshore industry as regulations restrict the use of steels with a high yield to tensile strength ratio, which is a characteristic of high­-strength and<br/>ultra high­-strength...

Measuring stress-strain behavior of mild steel at intermediate strain rates

Impacts on offshore installations and ships can cause strains at high rates. It is known that mild steel lower yield stress and hardening are strain rate dependent. Measuring this material behavior is not easy, as test results from many researchers, show heavy vibration. Vibration is normally referred to as ringing. This...

Mean Stress Effects in Temporal and Spectral Fatigue Analysis: Loading & Response and Resistance Contributions

Fatigue lifetime has proven to be a leading design parameter for naval vessels. In the field of fatigue analysis and design of welded joints, two overall methods are distinguished: the temporal and spectral approach. Using empirical models, the spectral approach is typically preferred due to its efficiency, even though damage estimates are...

Reducing payload motion during offshore operations

Offshore lifting operations must have reduced payload motion to increase safety and reduce operating time. When payload is retrieved from the splash zone to the deck, besides the crane block, no additional control can be applied on the underactuated system. Existing studies either assume more control over the payload or develop a control system...

Fatigue Safety Factors for Dynamic Power Cables: A reliability based approach

In contrast to traditional power cables for bottom-founded offshore wind turbines, power cables for floating wind turbines penetrate the water column and are exposed to cyclic loading. Due to the dynamic nature of the cable loading, the cables are prone to fatigue failure. Since the evaluation of the fatigue life of complex structures, like...

Motion compensated offshore knuckle boom crane: A mechanical feasibility study

To overcome the problem of wave-induced vessel motions on the crane tip, technologies have been developed to compensate for these motions. Most vessels nowadays, are equipped with dynamic positioning systems, these systems reduce the yaw, surge and sway movement of the vessel. This leaves, the motions roll, pitch and heave uncompensated. To...

An integrated sensor and process fault diagnosis framework for marine vessels

This research work tries to provide a model-based, distributed Fault Diagnosis (FD) framework that will eventually act as an early warning system for online monitoring of the marine propulsion process, in order to avoid future failures and accidents. Furthermore, the introduction of adaptive thresholds in the monitoring modules of the monitoring...

Feasibility Study of a Combined Wind and Solar Park within the Energy Storage Lake of Delta21

The penetration of the renewable energy sources in the global market has been constantly growing over the last years. This trend is expected to accelerate even more in the future due to the improving technologies, the economies of scale, the competitive supply chains and the improving developer experience. The main challenge for a faster and...

Experimental low frequency mooring analysis of a floating offshore wind turbine

Previous research into floating offshore wind turbines consistently shows some manner of discrepancy between numerical and experimental simulations when it comes to low frequency forces and motions. A part of solving this issue is the generation of accurate data for the calibration and validation of the numerical models, needed because of the...