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Abstract(s)
Os submarinos são meios que primam pela discrição, no entanto, os de propulsão convencional, como é o caso dos portugueses, necessitam de vir regularmente
à cota periscópica para recarregarem as suas baterias, ficando mais vulneráveis e
expostos ao adversário. Para minimizar esse efeito, foram criados os sistemas AIP -
"Air Independent Propulsion", cujo principal objetivo é a produção de energia com
o submarino totalmente submerso.
Sendo estes sistemas relativamente jovens, e dado o seu desenvolvimento
tecnológico emergente, torna-se necessária a criação de uma ferramenta que auxilie
eficazmente na escolha do sistema mais adequado aos submarinos portugueses. Este
trabalho tem como objetivo o desenvolvimento de um sistema de apoio à decisão
(SAD) que auxilie nessa seleção.
Para a construção do sistema, foi necessário efetuar um estudo comparativo
entre os quatro sistemas AIP existentes, nomeadamente as células de combustível,
os motores de ciclo Stirling, as turbinas a vapor de ciclo fechado e os motores a
Diesel de circuito fechado, por forma a extrair as características mais relevantes e
essenciais à construção do sistema.
O SAD baseia-se então num sistema difuso de duas fases baseado no modelo
de Mamdani. A primeira fase permite a obtenção de três valores de referência que
servem de auxílio no processo de decisão ao nível operacional, económico e ambiental.
A segunda fase usa esses três valores para criar um valor percentual de recomendação
de seleção do sistema. As regras lógicas base do sistema foram criadas apoiandose nas respostas obtidas num questionário realizado a 21 especialistas versados no
assunto.
Por fim, é aplicado o sistema difuso aos quatro tipos genéricos de AIP’s
para apurar tanto o nível de recomendação como também os valores das dimensões
da primeira fase.
Submarines are means that excel on covertness, however, those with conventional propulsion, such as the Portuguese, need to come regularly to the periscopic deph to recharge their batteries, becoming more vulnerable and exposed to the opponent. To minimize this effect, the AIP systems - "Air Independent Propulsion"were created, whose main objective is the production of energy with the submarine fully submerged. As these systems are relatively young, where their technological development is emerging, it’s necessary to create a tool that will efficiently and effectively help in choosing the most suitable system for Portuguese submarines. Thus, this work aims to develop a decision support system to assist in this selection. For the construction of the system, it was necessary to carry out a comparative study between the four existing AIP systems, namely fuel cells, Stirling cycle engines, closed cycle steam turbines and closed cycle diesel engines, in order to extract the most relevant and essential characteristics for the construction of the system. The system is then based on a two-phase fuzzy system based on the Mamdani model. The first phase allows the obtaining of three reference values that serve as an aid in the decision process at the operational, economic and environmental level. The second phase uses these three values to create a percentage system selection recommendation value. The logical rules base of the system were created based on the answers obtained in a questionnaire carried out to 21 experts versed in the subject. Finally, the fuzzy system is applied to the four generic types of AIP’s to determine both the level of recommendation and the values of the dimensions of the first phase.
Submarines are means that excel on covertness, however, those with conventional propulsion, such as the Portuguese, need to come regularly to the periscopic deph to recharge their batteries, becoming more vulnerable and exposed to the opponent. To minimize this effect, the AIP systems - "Air Independent Propulsion"were created, whose main objective is the production of energy with the submarine fully submerged. As these systems are relatively young, where their technological development is emerging, it’s necessary to create a tool that will efficiently and effectively help in choosing the most suitable system for Portuguese submarines. Thus, this work aims to develop a decision support system to assist in this selection. For the construction of the system, it was necessary to carry out a comparative study between the four existing AIP systems, namely fuel cells, Stirling cycle engines, closed cycle steam turbines and closed cycle diesel engines, in order to extract the most relevant and essential characteristics for the construction of the system. The system is then based on a two-phase fuzzy system based on the Mamdani model. The first phase allows the obtaining of three reference values that serve as an aid in the decision process at the operational, economic and environmental level. The second phase uses these three values to create a percentage system selection recommendation value. The logical rules base of the system were created based on the answers obtained in a questionnaire carried out to 21 experts versed in the subject. Finally, the fuzzy system is applied to the four generic types of AIP’s to determine both the level of recommendation and the values of the dimensions of the first phase.
Description
Keywords
Submarinos sistemas AIP difuso Mamdani