EXCEL® based simulation procedure for complex systems Life Cycle Cost estimation

The cost of acquiring and operating a system is usually identified as Life Cycle Cost (LCC) and represents one of the most important characteristics that determines its success on the market. Due to the increasing complexity of industrial systems, the estimate of such cost is not trivial and the need of specific software tool for LCC analysis is often mandatory. Particularly difficult is the estimate of the cost figures related to the probabilistic behaviour of the system, as far as failure events and repair actions are concerned. In this paper the authors propose a new methodology, based on Monte Carlo method, that allows to estimate the LCC of the system through simulation of its dependability behaviour. Such procedure, which is implemented on Excel (R) sheets, is characterised. by general purpose characteristics and allows the designer to carry out the cost analysis also in those cases where, due to nonconventional system structure, traditional methods, such as Fault Tree or Reliability Block Diagram, cannot be utilised.