Thermal creep of granular breeder materials in fusion blankets

Continuum models for granular materials in fusion blankets are efficient tools for modeling of the nonlinear elastic behavior of pebble beds, granular particle flow caused by shear, volume compaction and hardening. The present paper describes how the material models used in finite element analyses can be extended in order to account additionally for thermally activated creep. The derived material model gives results which are in reasonable accordance with experimental data for pebble beds.