Effect of Geometric Changes in of WWER-1000 Reactor’s Fuel Assemblies on their Fuel Burnup Parameter

The prediction of fuel burnup of fuel assemblies in nuclear reactors is one of the most important issues in nuclear engineering and reactor physics. Currently, many researchers in different countries are working on improving fuel burnup in nuclear reactors and increasing their economic and safety indicators. The DRAGON4 code is a cell and fuel burnup calculation code which was developed at Montreal Polytechnic University of Canada. In this study, at first, the DRAGON4 code was verified for a fuel assembly of Bushehr nuclear power plant and then, the fuel burnup changes due to geometric changes in the mentioned fuel assembly have been investigated. Results of this simulation prove the validity of fuel rod pitch with consideration of safety and economy aspects in Bushehr nuclear power plant fuel assemblies.