BLOCKAGE2.5R, Plug of Emergency Core Cooling Suction Strainers by Debris BWR

1 - Description of program or function: BLOCKAGEV2.5R is an integrated calculational method with graphic user's interface for evaluating the potential for loss of emergency core cooling systems pump net positive suction head margin due to insulation/other debris layer buildup on suction strainers following a postulated loss of coolant accident in boiling water reactors. Blockage incorporates the results of multi-year NRC sponsored research documented in NUREG/CR-6224. It also provides a framework into which user can input plant-specific/insulation-specific information for performing analysis in accordance with Regulatory Guide 1.82, Rev. 2. 2 - Methods: Modularized approach for parametrically treating different phenomena: debris generation, debris transport, debris cake buildup, and head loss. 3 - Restrictions on the complexity of the problem: Relies heavily on user specified information and no small LOCA models