Analysis of the Total Instantaneous Blockage accident consequences in the innovative inherently-safe CADOR SFR core

•CADOR is an inherently-safe SFR core based on an enhanced Doppler effect.•Core behavior when facing a TIB transient is studied using a fast-running tool.•The transient kinetic is slower than in more conventional homogeneous cores.•High thermal inertia and low power of subassemblies explain this behavior.•The molten fuel propagation mode is identified to be the most influent parameter.