Pulsed Activation Modeling for Chamber Materials of IFE Power Reactors and Experimental Facilities

Inertial confinement fusion (ICF) devices, both test/experimental facilities and fusion energy (IFE) power plants, will operate in a pulsed mode. However, the pulsing schedule in these devices is very different, and it could range from one shot every several days in an experimental facility to some Hz in IFE reactors. The main objective of the present work is to determine whether or not a continuous-pulsed (CP) approach could be an accurate and practical methodology in modeling the pulsed activation experienced by chamber materials of both types of devices. In testing the applicability of the CP irradiation model, we used materials and neutron environment scenarios of the HYLIFE-II reactor and the NIF experimental facility. It is demonstrated that a CP approach consisting of a continuous irradiation period followed by a series of only a few pulses prior to shutdown, can efficiently model the real pulsed operating regimes of the chamber materials, in terms of both accuracy and CPU time consumption. Pros and cons of the model when compared with an equivalent steady-state (ESS) method are discussed, and comparison with the exact pulsed (EP) modeling is also performed.