Development of A-LITE Model for Use in ATTILA Radiation Transport Finite Element Analysis of the ITER Lower Divertor Region

Neutron transport modeling of the ITER reactor structure including modeling the impact of potential neutron streaming along the divertor cassette requires a detailed 3-D CAD solid model of the ITER sector. An all-inclusive, full-scale CAD geometry model of a 40 degree section of the ITER reactor structure was developed for analytical use with the ATTILA^TM radiation transport code. The source geometry and model used was the reference 1/10th scale A-LITE 3 model provided by the ITER Project Office for radiation transport calculations. Model upscaling, examination, CAD-based cleanup and modifications were performed on each component using the commercial CAD software, SolidWorks. Based on the modified components a new full scale solid model of the ITER section including divertor cassettes was developed in order to ease the implementation of additional diagnostic components being designed by various parties.

Geometry repair and modification operations were performed with the goal of obtaining a Parasolid model that would successfully import into and mesh in ATTILA. Many components were re-modeled in order to avoid faulty geometry entities that were identified after the scaling to full-size. This paper will discuss the development of this A-LITE CAD model, and its meshing in ATTILA.