PNNL

Abstract

Westinghouse introduced six (6) Lead Test Assemblies (LTAs) of the VVER1000 fuel type in the South Ukraine Unit 3 reactor. This design included advanced fuel assembly features, which have performed satisfactorily through three (3) annual cycles of operation. These fuel assemblies will be operated for a fourth cycle. This design is suitable for multi-region application, remedies known problems with fuel in this reactor type, and addresses competing technical requirements. The design has been further enhanced to include features that eliminate assembly bow leading to incomplete control rod insertion, reduce the potential for grid-to-rod fretting, increase fuel economy, all while being hydraulically & mechanically compatible with the competitor core and multiple competitor fuel types.