Framatome ANP's ATRIUM™ fuel assemblies for boiling water reactors (BWRs) offer high operational reliability and excellent fuel utilization to reduce fuel-cycle costs. These characteristics help customers remain competitive in today's deregulated power markets.
       ATRIUM fuel assemblies are available for all BWR designs and can be manufactured with enriched natural uranium, as well as enriched reprocessed uranium (ERU) or mixed-oxide (MOX) fuel.

High Fuel Reliability at Ever Higher Burnups
By August 2000, more than 8,300 ATRIUM fuel assemblies have been used in numerous BWR plants all over the world including Germany, Sweden, Finland, Switzerland, the US and Taiwan. The maximum assembly burnup attained so far is 60 MWd/ kgU, just a small step away from the 70 MWd/kgU target that will be reached in 2001. These fuel assemblies, despite the continual increase in burnup, have achieved an average annual fuel failure rate (not counting failures due to debris-induced fretting) of less than 0.5x10^-5.
       Advanced cladding materials contribute to a high degree of reliability. For example, fuel assemblies containing Zircaloy-2 clad tubes with iron-enhanced zirconium liners - a cladding variant that was commercially deployed for the first time in 1993 - have suffered only one failure, caused by debris entrained in the fuel assembly from the top.

Serving Customers with Quality and Experience
Framatome ANP's high-quality fuel production minimizes costs, makes licensing easier and forms the cornerstone for reliable and economical reactor operation. It also helps protect the environment and conserve resources. All-inclusive expertise in nuclear systems and processes, know-how from thousands of service projects and in-core fuel management skills gained from hundreds of operating cycles contributes to Framatome ANP's broad-based experience. Customers also benefit from years of experience with licensing procedures worldwide and the comprehensive support provided for all issues related to licensing.

The ATRIUM 10 Concept - A Wide Range of Benefits Founded on Experience and Innovation Our ATRIUM 10 fuel assemblies contain 91 fuel rods arranged in a 10x10 array, eight of these being part-length rods. The square internal water channel, which occupies nine (3x3) lattice positions, supplies non-boiling water to the center of the fuel assembly. This, along with the part-length fuel rods, results in a more even power distribution across the fuel assembly and thus in optimum fuel utilization. At the same time, the water channel serves as a load-bearing structure, making tie rods superfluous and reducing the mechanical loads imposed on the fuel rods during operation and refueling.

ULTRAFLOW Spacer - Optimum Fuel Rod Cooling for High Operational Flexibility In the ULTRAFLOW™ spacer, the swirl vanes protruding into the center of the subchannels between the fuel rods direct water droplets from the two-phase mixture onto the fuel rods, resulting in greater design margins with respect to critical power ratios. A special variant of the ULTRAFLOW spacer made of Inconel (instead of the usual Zircaloy) was developed for the latest generation of ATRIUM

SmallHole and FUELGUARD -
Lower Tie Plates That Keep All Debris Out
Two different lower tie plates with integral debris filters are available for ATRIUM fuel assemblies: SmallHole, which uses a perforated plate to filter out debris, and FUELGUARD™, in which debris is retained by a parallel array of curved blades. Both designs guarantee an exceptionally high debris-retention efficiency, significantly reducing the probability of fuel damage from debris-induced fretting.