Fuel Handling Solutions to Power Pulse at Bruce 'A'

Abstract

In response to the discovery of the power pulse problem in March of 1993, Bruce A has installed flow straightening shield plugs in the inner zone channels of all units to partially reduce the gap and gain an increase in reactor power to 75% FP. After review and evaluation of solutions to manage the gap, including creep compensators and long fuel bundlesl efforts have focused on a different solution involving reordering the fuel bundles to reverse the burnup profile. This configuration is maintained by fuelling with the flow and providing better support to the highly irradiated downstream fuel bundles by changing the design of the outlet shield plug. Engineering changes to the fuel handling control system and outlet shield plug are planned to be implemented starting in June 1996 thereby eliminating the power pulse problem and restrictions on reactor operating power.