• Free vibration
• Hexagonal Geometry
• Fluid Structure Interaction

This work is related to fluid-structure interaction analyses for high confined configurations,
as in a SFR core.
Sudden liquid or gas evacuation between assemblies could lead to overall core
movements (flowering and compaction) causing variations of core reactivity. The
comprehension of the structure behavior during the evacuation could improve the
knowledge about some SCRAMs for negative reactivity occurred in Phénix reactor
and could contribute on the study of the dynamic behavior of FBR core.
An experimental facility representing a portion of core (PISE-2C) was designed
for this purpose at CEA-Saclay. Another experimental apparatus (PISE-
1A) composed by one hexagonal rod was also designed to test the dynamic characteristics.
A 2D numerical model is also developed to resolve Navier-Stokes equations
coupled with structure dynamic equation in order to analyze some FSI mechanisms.
The numerical method is validated by the comparison with an analytical model
existing in literature and another one specifically developed and more related to
phenomena in our concern. A comparison with experimental results is attempted
too.