Radiation-shielding calculations for the UPTF gamma-ray densitometer. [PWR]

The UPTF densitometer is part of the international 2D/3D Program, a joint reactor safety research effort by the United States, West Germany, and Japan. UPTF is a full scale PWR upper plenum facility to be used for refill and reflood tests. It is a non-nuclear facility which will use programmed steam and water injection to study two and three dimensional flow phenomena. UPFT includes full scale PWR hot and cold legs and the subject densitometers are to be placed on the four horizontal hot legs and one horizontal broken cold leg. The mechanical design of the UPTF densitometer was iterated against the radiation shielding design in order to ensure that the dose rate at the surface of the densitometer would not exceed 2.5 mR/h. The equations and parameters used in the radiation shielding calculations are discussed. The actual calculations and parameters used for each dose point are outlined.