Thermo-mechanical analyses of HELICA and HEXCALIBER mock-ups

As benchmark exercises, HELICA and HEXCALIBER mock-ups have been launched in the HE-FUS 3 facility at ENEA Brasimone for investigating the thermo-mechanical behaviour of pebble beds. The present material model of pebble beds, based on the modified Drucker-Prager-Cap model, has been implemented in the commercial finite element package, ABAQUS. The overall behaviour of the lithium orthosilicate cassette (HELICA) and the interactions of ceramic breeder pebble beds and beryllium pebble beds (HEXCALIBER) are studied numerically. The finite element analyses show the temperature distribution of the mock-up experiments, as well as the stress–strain fields. The predictions of HELICA mock-up are compared with the experiments, including the temperature measured by thermo-couples located inside the pebble beds and the lateral deformation of the cell.