A safety device for the neutron converter of the SPIRAL2 project

The system consists of a special device called Delay Window, (DW), which is designed as an integral part of the cooling panels of the neutron converter module. The DW is located between the neutron converter and the fission target. In case of neutron converter failure, this device will absorb the beam and will delay its impact on the UCx target; this delayed time is longer than the interlocks activation time, hence the primary beam operation is safely stopped. The working principle of the DW is based on the well known liquid lead technology. The conceptual design of the Delay Window is presented, as well as the results of the thermo-mechanical simulations and the tests of the prototype. Calculations are done for beam powers of 50 and 200 kW. Simulations are performed with ANSYS code.