Evaluation of feasibility index in the arrangement design of an offshore topside based on the automatic transformation of experts' knowledge and the fuzzy logic

In an offshore platform, many modules and equipment are placed on the limited space called topside, so that the space should be used efficiently. Furthermore, a sufficient space between equipment should be provided for the operability, maintainability, and safety. To guarantee suitable arrangement design, there are many requirements to be considered such as international codes and standards, including owners' own requirements. Meanwhile, the arrangement design of an offshore topside tends to rely on experts' knowledge and experiences. Due to the heavy dependence on experts' knowledge and experiences, consequently, a different arrangement can be derived according to a personal disposition, in spite of the same requirements. In addition, an unacceptable arrangement can be derived due to the omission of some requirements by a designer. To solve such problems, an expert system for the arrangement design of an offshore topside was proposed based on an arrangement evaluation model (AEM) in this study by expanding the previous study of authors for the arrangement design of a submarine. In addition, an arrangement template model (ATM) was proposed to store various data on the arrangement design of the offshore topside. To evaluate the applicability of the proposed expert system, a prototype program consisting of the AEM and the ATM was also developed here. Finally, this program was applied to a problem of a large FPSO topside. The results showed that the proposed system can be used to evaluate the given alternatives for the arrangement design of the offshore topside.