Presentation Information
[2B12]Evaluation of the effect of random storage in clearance measurement containers on the radioactivity conversion factor (4)Development of 3D simulation tool
*Masato Watanabe1, Toshio KUZUYA2 (1. Chubu Electric Power, 2. Techno Chubu)
Keywords:
clearance,Radioactivity measurement,Shielding calculation,Radioactive Source,Density uneven distribution
We developed a calculation tool to simulate the radiation measurement in the clearance measurement device used in the decommissioning of Hamaoka Nuclear Power Plant Units 1 and 2, And we confirmed the basic operation of this tool.In this device, shredded pieces (scrap metal) weighing about 1 ton in total are stored in a measurement container, and the 1.33 MeV gamma rays of Co-60 are measured with a Ge semiconductor detector and converted into radioactivity.The calculation tool consists of (1) storage simulation and (2) shielding calculation. A three-dimensional physics engine was used to simulate the state in which cut pieces with multiple shapes are randomly stored in the measurement container.Next, the cut pieces stored in the container are converted into detailed voxels of 1 mm to 50 mm, and a three-dimensional shielding calculation is performed. The radiation source for each voxel is proportional to the surface area of the surface of the cut pieces contained in the voxel.