Quintessa

Reactor Inspection Software

Quintessa develops software to assist in decisions on which fuel channels in nuclear reactors should undergo periodic inspections taking account of operational constraints and competing requirements for data.

Periodic inspections are carried out on the cores of the British fleet of Advanced Gas-Cooled Reactors (AGRs).  Each graphite reactor core has about 300 fuel channels, but it is only possible to inspect a small fraction of these during a single outage. Ready access to existing data is a prerequisite for making good decisions on which channels to inspect.   There is a large amount of data available from previous inspections on the state of the core which informs safety cases for continued operation.

Data visualisation is an important part of processing this information.  Not only is a graphical representation of data easy to understand, but the human eye can often identify important patterns and trends.  Anomalies that may not be otherwise obvious can spring out from the page if the data is visualised in an effective way.  CHANSELA, which has been developed for EDF Energy, employs core maps to visualise reactor data. These are top‑down views of the reactor core.

The primary function of the CHANSELA software is to aid the choice of channels to inspect during reactor outages, but an important secondary function is the ability for the user to visualise the data that informs such decisions.  It allows the user to visualise core data such as fuel element burnup and channel power, including histograms of the data across the whole core (or specific rings of channels), or plots of properties against time (or core burnup) for specified channels.

Software packages such as CHANSELA provide support to those making complex decisions about reactor inspections and safety cases, resulting in both safety and economic benefits.