Application of three-dimensional computer solids modeling to TMI-2 [Three Mile Island Unit 2] defueling activities

In February 1985 work was begun to develop a three-dimensional computerized solids model of the Three Mile Island Unit 2 (TMI-2) reactor building systems and facilities. Although it was initially planned to use this model to support the acquisition of data for radiological characterization, the unique ability of the modeling system to integrate plant configuration data into a single source made it an ideal tool for supporting various other TMI-2 recovery engineering activities as well. In addition to the reactor building model, models of the auxiliary and fuel handling buildings and a very detailed model of the TMI-2 reactor have also been developed. The application and use of the reactor model to support activities related to reactor vessel defueling and reactor components disassembly are the primary subjects of this paper, particularly as they relate to each area of the TMI-2 defueling organization