Reactor loose-part activity

Measured Loose-Part drag coefficients were used to calculate reactor loose- part activity as a function of mass and reactor coolant flow conditions for prototype loose-part shapes. The maximum loose-part mass that could be lev itated in vertical flow and the maximum loose-part mass that could impact a recirculating steam generator tube sheet were calculated as a function of flow velocity for Pressurized Water Reactor (PWR) cold and operating primar y coolant water properties. The energy of steam generator tube sheet impact s was calculated as a function of mass at cold and operating conditions for a 1130 MW Pressurized Water Reactor. Substantial decreases in active loose -part mass and impact energy occurred between cold and hot flow conditions due to the decrease in water density and viscosity. Loose-parts with higher surface area to mass ratios had higher maximum levitation masses and impac t energies. These calculations provide insight into the range of active loo se-part mass and impact energy as a function of now conditions. The associa ted range in detected signal amplitude can assist in the screening and eval uation of unknown loose-part signals. The loose-part activity modeling meth ods can be used to extend the results to other reactor coolant system flow conditions and geometries. (C) 1998 Elsevier Science Ltd. AII rights reserv ed.