Discrete event simulation modeling for RAMI analysis of normal and upset plant operation

We have spent the past 4 years applying discrete event simulation to estimate the availability and production capacity of a nuclear material production facility. In the course of this work, we have uncovered several issues that are discoverable only through a dynamic analysis. For example, it was found that specific temporal relationships between failures in cyclically connected processes can induce gridlock in the production system. These types of gridlock conditions had been observed in similar older facilities but were not thought to be a potential problem in the new design. This discovery early in the design process prevented expensive retrofits later in the plant's life cycle. In this and several other instances, dynamic analysis of plant operations has had a substantial impact on design. Such impacts have repeatedly justified investment in this analysis technique.