A functional model-based approach for ship systems safety and reliability analysis – application to a cruise ship lubricating oil system

Kritonas Dionysiou, Victor Bolbot, Gerasimos Theotokatos

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)
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The lubricating oil systems are essential for ensuring the safe and reliable operation of the cruise ships power plants as demonstrated by recent incidents. The aim of this study is to investigate the safety enhancement of a cruise ship lubricating oil system by employing safety, reliability, availability and diagnosability analyses, which are based on the system functional modelling implemented in the MADe™ software. The safety analysis is implemented by combining a Failure Modes, Effects and Criticality Analysis and the systems functional Fault Tree Analysis. Subsequently, Reliability Block Diagrams are employed to estimate the system reliability and availability metrics. The MADe™ toolbox for determining sensors locations is employed for a more advanced diagnostic system development. A number of design modifications are proposed and the alternative configurations reliability metrics are estimated. The derived results demonstrate that the suction strainer and the lubricating oil pump are the most critical system components. Seven additional sensors are proposed to enhance the original system design. Compared with the original system design, the investigated alternative designs exhibit significantly lower probabilities of failure and higher values of availability.

Original languageEnglish
Pages (from-to)228-244
Number of pages17
JournalProceedings of the Institution of Mechanical Engineers, Part M: Journal of Engineering for the Maritime Environment
Issue number1
Early online date18 Mar 2021
Publication statusE-pub ahead of print - 18 Mar 2021


  • lubrication oil system
  • cruise ships
  • functional modelling
  • failure modes
  • effects and criticality analysis
  • fault tree analysis
  • reliability block diagrams
  • MADe™ software

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