Type 13 Design A Port Side; SS Northern Wind

Stamp of "166"; Discontinued stamp JUL 29 1918

Type 13 Design B Starboard Side; SS Northern Wind

Print No 74

Type 13 Design B Port Side; SS Northern Wind

Print No. 71

Type 13 Design D Port Side; SS Northern Wind

Print No:183.; Initials Lower Right: ELW (Everett Longley Warner)

Type 13 Design E Starboard Side; SS Northern Wind

Print No:80

Type 13 Design E Port Side; SS Northern Wind

Print No: 66

Type 13 Design F Starboard Side; SS Northern Wind

Print No: 80; Initials Lower Left: WH; Initials Lower Left: DN; Initials Lower Left: GY

Type 13 Design F Port Side; SS Northern Wind

Print No:66; Initials Lower Left: WH; Initials Lower Left: DN; Initials Lower Left: GY

Type 13 Design G Starboard Side; SS Northern Wind

Print No:67; Initials Lower Left: OL; Initials Lower Left: HD; Initials Lower Left: RN; Initials Lower Right: ELW (Everett Longley Warner)

Type 13 Design G Port Side; SS Northern Wind

Print No:70; Initials Lower Left: OL; Initials Lower Left: HD; Initials Lower Left: RN; Initials Lower Right: ELW (Everett Longley Warner)

Influence of advanced load simulation models on fatigue design of jackets for offshore wind turbines.

Constant developments in the field of offshore wind energy have increased the range of water depths at which wind farms are planned to be installed. Therefore, in addition to monopile support structures suitable in shallow waters (up to 30 m), different types of support structures, able to withstand severe sea conditions at the greater water depths, have been developed. For water depths above 30 m, the jacket is one of the preferred support types. Jacket represents a lightweight support structure, which, in combination with complex nature of environmental loads, is prone to highly dynamic behavior. As a consequence, high stresses with great variability in time can be observed in all structural members. The highest concentration of stresses occurs in joints due to their nature (structural discontinuities) and due to the existence of notches along the welds present in the joints. This makes them the weakest elements of the jacket in terms of fatigue. In the numerical modeling of jackets for offshore wind turbines, a reduction of local stresses at the chord-brace joints, and consequently an optimization of the model, can be achieved by implementing joint flexibility in the chord-brace joints. Therefore, in this work, the influence of joint flexibility on the fatigue damage in chord-brace joints of a numerical jacket model, subjected to advanced load simulations, is studied.

Methodology for the design of offshore wind farms

Although still in an early stage, offshore wind development is now characterized by a boom process. This leads to the necessity of applying an integral management model for the design of offshore wind facilities, being the purpose of the model to achieve technical, economical and environmental viability, all within a sustainable development framework. The foregoing led to the research project exposed in this paper, consisting of drawing up an offshore wind farms methodological proposal; this methodology has a global and/or general nature or point of view whilst searching for optimization of the overall process of operations leading to the design of this type of installations and establishing collated theoretical bases for the further development of management tools. This methodological proposal follows a classical engineering thought scheme: it begins with the alternatives study, and ends with the detailed design. With this in mind, the paper includes the following sections: introduction, methodology used for the research project, conditioning factors, methodological proposal for the design of offshore wind farms, checking the methodological proposal, and conclusions

Components of a Wind Tunnel Balance: Design and Calibration

Components of a Wind Tunnel Balance: Design and Calibration

Dimensionless wave height parameter for preliminary design of scour protection in offshore wind farms

This article describes the results of an investigation aimed at the analysis methods used in the design of the protections against scour phenomenon on offshore wind farms in transitional waters, using medium and large diameter monopile type deep foundations.

Uncertainties in the design of support structures and foundations for offshore wind turbines

Offshore wind industry has exponentially grown in the last years. Despite this growth, there are still many uncertainties in this field. This paper analyzes some current uncertainties in the offshore wind market, with the aim of going one step further in the development of this sector. To do this, some already identified uncertainties compromising offshore wind farm structural design have been identified and described in the paper. Examples of these identified uncertainties are the design of the transition piece and the difficulties for the soil properties characterization. Furthermore, this paper deals with other uncertainties not identified yet due to the limited experience in the sector. To do that, current and most used offshore wind standards and recommendations related to the design of foundation and support structures (IEC 61400-1, 2005; IEC 61400-3, 2009; DNV-OS-J101, Design of Offshore Wind Turbine, 2013 and Rules and Guidelines Germanischer Lloyd, WindEnergie, 2005) have been analyzed. These new identified uncertainties are related to the lifetime and return period, loads combination, scour phenomenon and its protection, Morison e Froude Krilov and diffraction regimes, wave theory, different scale and liquefaction. In fact, there are a lot of improvements to make in this field. Some of them are mentioned in this paper, but the future experience in the matter will make it possible to detect more issues to be solved and improved.