Floating Substations for Commercial-Scale Floating Windfarms

2021 ◽  
Author(s):  
Justin Jones ◽  
Ian Childs
Keyword(s):  
Water Depth ◽  
Direct Current ◽  
Wind Farms ◽  
Pilot Projects ◽  
Hull Form ◽  
Hydrodynamic Analysis ◽  
Commercial Scale ◽  
Hull Forms ◽  
Ancillary Equipment ◽  
Structural Code

Abstract As floating wind farms move from pilot projects to commercial-scale installations they will move further offshore and into deeper water. There will be a requirement for offshore substations to deliver the electricity to shore, for which floating support structures will be the preferred solution. This paper describes the challenges and development of solutions for commercial-scale HVAC and HVDC floating offshore substations. Two different floating substation concepts have been developed. Layouts for the electrical and ancillary equipment were initially developed, to enable efficient packaging and structural efficiency for the topsides. By integrating the hull and topsides, the overall mass of the structure is minimised, benefitting stability and reducing hull size. Hydrodynamic analysis of the substructures was performed and structural code checks on the hull and topsides were carried out in Sesam. Mooring designs for each structure for 250m water depth have been developed and analysed in Orcaflex. It is likely that alternating current (HVAC) export to shore will be used for shorter transmission distances and direct current (HVDC) will be used for longer transmission distances. HVDC and HVAC floating substations will have quite different hull forms. The larger topsides footprint and greater mass of the HVDC conversion equipment make a conventional semi-submersible hull form efficient when allied to a stressed-skin topsides structure. The smaller footprint, lighter weight and differing requirements for protection from the elements of the HVAC topsides make this inefficient, so a deep draught semi-submersible with a hybrid topsides is the preferred solution. It is concluded that floating substations suitable for large, commercial-scale wind farms will be the chosen solution for anything other than shallow water or close to shore.

Geometrical Characteristics of Fishing Boats Series of ITU

2007 ◽  
Vol 44 (02) ◽  
pp. 125-137
Author(s):  
Muhsin Aydin ◽  
Aydin Salci
Keyword(s):  
Computer Program ◽  
The Body ◽  
Hull Form ◽  
The Third ◽  
Geometrical Characteristics ◽  
Fishing Boat ◽  
Technical University ◽  
Hull Forms

In the present paper, first 13 hull forms of fishing boats with different block coefficients were generated. Later, 26 hull forms of fishing boats with two different ratios of length to beam were generated by utilizing previous hull forms of fishing boats mentioned. In total, 39 fishing boats were generated. This series is called "Fishing Boats Series of ITU" (Istanbul Technical University). In this Series, the forms of the body stations and beams of the boats are the same for equal block coefficient and different lengths. The ratio of the beam of any station at any waterline to the beam of boat, Bz/B varies with respect to block coefficient, CB. These variations have been represented with the third-degree polynomials. Thus, a hull form of the fishing boat in the desired length and block coefficient can be obtained by using these polynomials. For this purpose, a computer program called "Turetme" was developed. Finally, by using this program, three hull forms of fishing boats were obtained and presented here.

Ship Hull Form Optimization Using Artificial Bee Colony Algorithm

2014 ◽  
Author(s):  
Fuxin Huang ◽  
Lijue Wang ◽  
Chi Yang
Keyword(s):  
Drag Reduction ◽  
Artificial Bee Colony ◽  
Interpolation Method ◽  
Ship Hull ◽  
Mathematical Functions ◽  
Hull Form ◽  
Abc Algorithm ◽  
Bee Colony ◽  
Hull Forms ◽  
Fast Flow

In this paper, artificial bee colony (ABC) algorithms are introduced to optimize ship hull forms for reduced drag. Two versions of ABC algorithm are used: one is the basic ABC algorithm, and the other is an improved artificial bee colony (IABC) algorithm. A recently developed fast flow solver based on the Neumann-Michell theory is used to evaluate the drag of the ship in the optimization process. The ship hull surface is represented by discrete triangular panels and modified using radial basis function interpolation method. The developed optimization algorithms are first validated by benchmark mathematical functions with different dimensions. They are then applied to the optimization of DTMB Model 5415 for reduced drag. Two optimal hull forms are obtained by the ABC and the IABC algorithms. A large drag reduction is obtained by both of the algorithms. The optimal hull form obtained by the IABC algorithm has larger drag reduction than that of the hull form from the ABC algorithm. The results show that two ABC algorithms can be used for optimizing ship hull forms and the IABC algorithm has better performance than the ABC algorithm for the tested case in ship hull form optimization.

A Comparison of Several Strategies to Optimize a Ship’s Aft Body

2011 ◽  
Vol 27 (04) ◽  
pp. 202-211
Author(s):  
Auke van der Ploeg
Keyword(s):  
Viscous Flow ◽  
Scale Effects ◽  
Full Scale ◽  
Ship Hull ◽  
Hull Form ◽  
Wake Field ◽  
Hull Forms ◽  
Definition Of

This paper describes a procedure to optimize ship hull forms, based on double body viscous flow computations with PARNASSOS. A flexible and effective definition of parametric hull form variations is used, based on interpolation between basis hull forms. One of the object functions is an estimate of the required power. In this paper we will focus on how to improve this estimate, by using the B-series of propellers. Results of systematic variations applied to the VIRTUE tanker together with scale effects in the computed trends will be discussed. In addition, we will demonstrate how the techniques discussed in this paper can be used to design a model that has a wake field that strongly resembles the wake of a given containership ship at full scale.

Hydrodynamic Analysis of Tension Based Tension Leg Platform

2012 ◽  
Author(s):  
D. S. Bhaskara Rao ◽  
R. Panneer Selvam ◽  
Nagan Srinivasan
Keyword(s):  
Water Depth ◽  
Vertical Plane ◽  
Hydrodynamic Analysis ◽  
Response Characteristics ◽  
Deep Waters ◽  
Economical Design ◽  
Motion Responses ◽  
Offshore Industry ◽  
Response Amplitude Operators ◽  
Water Depths

Tension Leg Platforms (TLPs) are one of the best options for offshore industry in deep waters due to proven motion response characteristics. These are water depth sensitive structures and the motion responses in vertical plane motions (heave, roll and pitch) are critical for a TLP. Tension Based TLP (TBTLP) is a new concept and finds application in much deeper waters. A provision of a tension base at mid-depth results in an economical design of TLP. In fact, the TLP installed at a certain depth without any modifications can be made to be deployed in much deeper water depths by means of a tension base. In this paper, the concept of TBTLP is highlighted and hydrodynamic analysis of the chosen platform has been carried out using ANSYS AQWA package. The motion responses in terms of Response Amplitude Operators (RAOs) of TBTLP with one Tension Base in surge, heave and pitch have been obtained and compared with a TLP without a tension base.

Future Research Vessels

2001 ◽  
Vol 35 (3) ◽  
pp. 43-45
Author(s):  
Larry P. Alkinson
Keyword(s):  
United States ◽  
Academic Research ◽  
The United States ◽  
Advanced Technology ◽  
Research Vessel ◽  
Future Research ◽  
Woods Hole Oceanographic Institution ◽  
Hull Form ◽  
The People ◽  
Hull Forms

The academic research vessel fleet in the United States is embarking on a great experiment. By 2004 we will know if SWATH vessels such as the Kilo Moana and the possible built Woods Hole Oceanographic Institution coastal SWATH have such great advantages that all future vessels will be of SWATH design. Or, we will find that the two hull forms have distinct niches and the fleet will evolve with a strategic mix. Regardless of the future hull form research vessels will grow in size to accommodate advanced technology and the people to run and maintain it. The research vessel will become an office and laboratory at sea with seamless communication to the shore for the oceanographer.

scholarly journals Research of velocity field in vessel’s wake current from «side by side» mooring

2020 ◽  
Author(s):  
Е.Ю. Чебан ◽  
Д.В. Никущенко ◽  
О.В. Мартемьянова ◽  
Н.Е. Зотова
Keyword(s):  
Laboratory Experiments ◽  
Field Experiments ◽  
Fluid Velocity ◽  
Fluid Flows ◽  
Relative Displacement ◽  
Water Area ◽  
Hull Form ◽  
Sensor Field ◽  
Flow Velocity Measurement ◽  
Hull Forms

В настоящей работе приведены результаты исследования полей скоростей, возникающие при обтекании потоком жидкости судов в счале в зависимости от формы корпуса судов, расстояния между ними и относительного смещения корпусов судов лабораторными, натурными и численными методами. Лабораторные эксперименты выполнялись с применением ADV-датчика. Натурные эксперименты проводились на акватории р. Волга с двумя танкерами. Для численного моделирования использовался программный комплекс FineMarineTM. Выполненное сопоставление результатов измерений скорости потока различными методами, показало достаточную сходимость результатов. Получено, что для моделей судов с упрощенными обводами характер спутного потока жидкости существенно зависит от расстояния между моделями. Показано, что увеличение расстояния между судами может приводить к значительному увеличению скорости спутного течения в раннем следе за счаленными корпусами, но при относительном продольном смещении судов такой картины не наблюдается. This work presents the results of the study of velocity fields that occur when a stream of fluid flows along “side by side” vessels’ mooring, depending on the hull forms, the distance between them and the relative displacement of the hull by laboratory, full-sized and numerical methods. Laboratory experiments were performed using an ADV-sensor. Field experiments were conducted with two tankers in the water area of ​​the river Volga. The FineMarineTM software package was used for numerical simulation. A correlation of the results of the flow velocity measurement by various methods showed sufficient convergence of the results. It was found that the cocurrent stream of fluid pattern for models of vessels with simplistic hull form depends heavily on the distance between the models. It is shown that an increase in the distance between the vessels can lead to a significant increase in the fluid velocity of the concurrent stream in the early wake of the hulls of vessels’ mooring, but this picture is not observed with a relative longitudinal displacement of the vessels.

scholarly journals On the Development of Catamaran Hull Form for Fish Processing Vessel to Support Domestic Fishing Activities in Indonesia

Naše more ◽  
2021 ◽  
Vol 68 (3) ◽  
pp. 175-188
Author(s):  
Ahmad Fauzan Zakki ◽  
◽  
Deddy Chrismianto ◽  
Aulia Windyandari ◽  
Rizaldy Ilham
Keyword(s):  
Dynamic Stability ◽  
High Speed ◽  
Equation Model ◽  
Fish Processing ◽  
Hull Form ◽  
Initial Stage ◽  
Intact Stability ◽  
Principal Dimension ◽  
Hull Forms ◽  
Resistance Performance

Several advantages of multihull, such as catamaran, have been extensively discussed in the previous research. Therefore, this research focuses on developing a catamaran hull form for the fish processing vessel hull. The initial stage is determining the principal dimension and exploring the configurations of catamaran hull forms. The existing high-speed craft catamarans have been adopted to determine the parent model main dimensions using a linear regression equation model. Otherwise, the catamarans single demi-hull geometry was developed by converting and modifying the parent model hull form with enlarging the hull displacement to achieve the deadweight capacity and service speed requirements. The demi-hull spacing configuration with s/L 0.17, s/L 0.20, s/L 0.30, and s/L 0.40 on the resistance characteristics, intact stability, and sea-keeping behaviour were also explored. Furthermore, the comparisons with the previously proposed monohull were presented. Regarding the hull resistance performance, the analysis indicated that the catamaran hull form had better total resistance characteristics than the monohull on the service speed over 23 knots. In the case of intact stability, the analysis results presented that the catamaran hull form has better intact stability characteristics than the monohull. The dynamic stability of the catamarans also gave better dynamic stability at the heeling angle below 41.57°. Otherwise, the catamarans with s/L 0.17 and s/L 0.20 have lower dynamic stability than the monohull at the heeling angle larger than 41.57° and 58.03°, respectively. In the sea-keeping performance, the catamaran hull has shown an excellent rolling motion required for the offshore environment loading/unloading process. The large demi hull spacing of the catamarans hull can reduce the effect of the wave creating load on the roll motion response at the Beam Sea.

scholarly journals A Spatial Analysis of the Potentials for Offshore Wind Farm Locations in the North Sea Region: Challenges and Opportunities

2020 ◽  
Vol 9 (2) ◽  
pp. 96 ◽  
Author(s):  
Gusatu ◽  
Yamu ◽  
Zuidema ◽  
Faaij
Keyword(s):  
Protected Areas ◽  
North Sea ◽  
Water Depth ◽  
Wind Farm ◽  
Wind Farms ◽  
Offshore Wind ◽  
Offshore Wind Farms ◽  
The North ◽  
Challenges And Opportunities ◽  
The North Sea

Over the last decade, the accelerated transition towards cleaner means of producing energy has been clearly prioritised by the European Union through large-scale planned deployment of wind farms in the North Sea. From a spatial planning perspective, this has not been a straight-forward process, due to substantial spatial conflicts with the traditional users of the sea, especially with fisheries and protected areas. In this article, we examine the availability of offshore space for wind farm deployment, from a transnational perspective, while taking into account different options for the management of the maritime area through four scenarios. We applied a mixed-method approach, combining expert knowledge and document analysis with the spatial visualisation of existing and future maritime spatial claims. Our calculations clearly indicate a low availability of suitable locations for offshore wind in the proximity of the shore and in shallow waters, even when considering its multi-use with fisheries and protected areas. However, the areas within 100 km from shore and with a water depth above –120 m attract greater opportunities for both single use (only offshore wind farms) and multi-use (mainly with fisheries), from an integrated planning perspective. On the other hand, the decrease of energy targets combined with sectoral planning result in clear limitations to suitable areas for offshore wind farms, indicating the necessity to consider areas with a water depth below –120 m and further than 100 km from shore. Therefore, despite the increased costs of maintenance and design adaptation, the multi-use of space can be a solution for more sustainable, stakeholder-engaged and cost-effective options in the energy deployment process. This paper identifies potential pathways, as well as challenges and opportunities for future offshore space management with the aim of achieving the 2050 renewable energy targets.

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