Controlling contamination transfer is a particularly significant issue, not only for the safety of nuclear facilities, but also for the protection of operators. Two complementary containment methods are used for this purpose: ventilation of facilities, and filtration of effluents before discharge into the environment. As in the case of aerosol physics, research concerning contamination transfer is at the crossroads between protection and safety-related issues. These topics include not only general activities spanning from development to qualification of physical models, computation tools and experimental techniques, but also specific activities focussed on characterization of contamination transfer in various accident situations, especially fire, the most probable risk in a nuclear facility. Our corresponding research programs therefore cover two main areas:
- general activities related to transfer, ventilation and filtration,
- activities specific to accident situations.
Two main areas of research :
General actions related to airborne contamination transfer, ventilation and filtration
– transfer within a ventilated area: development of near-field transfer models, implementation of a systems approach, evaluation of multi-dimensional computation tools,
- transfer throughout an entire facility: development of filtering models (efficiency and clogging, serial filtering), performance evaluation for gaseous contaminant purification systems, determination of simplification criteria for ventilation network modeling (SIMEVENT), contribution to the development of the new SYLVIA platform,
- experimental techniques for transfer assessment: improvement of metrology systems for gas and particlulate tracers, comparison of gas and aerosol transfers in ventilated enclosures.
Activities specific to accident situations
- fire: contamination suspension, clogging models applied to combustion aerosols, behavior of sectorization and containment equipment under severe temperature, pressure and humidity (STARMANIA program), impact of ventilation control in case of fire, contribution to SYLVIA platform development,
- UF6 leak: dispersion inside an area, behavior of filtering systems,
- total loss of ventilation: assessment of tools and models available, impact of wind, experimental qualification,
- efficiency of glove-box type containment under accident conditions: glove tearing, thermal effects, etc.