Banca de QUALIFICAÇÃO: SALVATORE VERDE

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : SALVATORE VERDE
DATE: 29/04/2021
TIME: 15:00
LOCAL: Sala virtual no Google Meet
TITLE:

OPTIMIZATION PROJECT BASED ON THE RELIABILITY OF A MULTILINE ANCHORAGE TAUT-LEG SYSTEM OF WIND TURBINES

KEY WORDS:

Multiline anchor system. Floating offshore turbine farm. Reliability-based optimization design. Computational experiment. Metamodels.

PAGES: 26
BIG AREA: Engenharias
AREA: Engenharia Civil
SUBÁREA: Estruturas
SPECIALTY: Mecânica das Estruturas
SUMMARY:

Great effort has been taken to mitigate the environmental impacts caused by fossil fuels. For instance, to reduce the cost per MWh, the Corewind (Cost Reduction Wind) project was started, in which the state of the art was outlined, and various scientific and technological innovation options were suggested for wind energy. Within them, the optimization of the anchoring system was suggested, which is considered responsible for about 20% of the costs of manufacturing, assembly, operation, maintenance and decommissioning of wind farms. For that purpose, several studies have been performed about multiline anchoring systems with shared lines and anchors devoted to offshore wind turbine farms. Despite several computer simulations have been performed using finite elements, only anchor systems in catenary configuration were analyzed. Catenary takes advantage of the weight of the line to keep the floating turbine on the site, and previous works considered essentially steel chain. This option has the drawback of having heavier, more expensive lines, but smaller and cheaper anchors, which must bear only horizontal forces. This type of system guarantees to be efficient, but it becomes unfeasible for deeper waters. In this last scenario, lighter prestressed fiber lines, called Taut-Leg, are more efficient, but require more expensive anchors, which must bear vertical forces also. Now, considering that innovative cheaper anchors have been suggested, capable of absorbing the same loads as the existing anchors, a good opportunity arose to seek for an optimal configuration of a Taut-Leg system. In reliability-based optimization design (RBDO), cost functions and constraints can be evaluated, for example, with the finite element method, which has the drawback of higher computational cost. A cheaper alternative is to use metamodels to build up the required functions, being able to speed up the RBDO. Aiming to expand the state of the art of the anchoring system, the following proposal is summarized. First, the metamodels of the representative functions of the physical phenomena under investigation will be built, using the Kriging method and the neural networks, which are efficient to capture the nonlinearities of the structural dynamic behavior of the anchoring system. Finally, with the mentioned functions, an RBDO of a wind farm Taut-Leg anchoring system with shared lines and anchors will be performed.

BANKING MEMBERS:
Interno - 1120928 - ADEILDO SOARES RAMOS JUNIOR
Externo à Instituição - FÁBIO MARTINS GONÇALVES FERREIRA - UFAL