This project focuses on two reactor design that are part of the High Temperature Gas-cooled Reactors (HTGR) that are prismatic HTRs and pebble bed reactors. HTGR are supposed to be build embedded in the ground and the current size of their control rod, which are plain rods and need to seat over the reactor or need to be slightly inserted for reactivity control, are contributing greatly to the height of the reactor building. Reducing the height of the building would contribute to lower the cost of construction significantly.
This project investigates the possibility of using the design of telescopic control rods instead of plain ones. It started with the identification of requirements that such control rods would need meet in terms of neutron absorption and in terms of failure modes both in normal operating regime and in accident scenario.
Currently a design of a control rod is being developed with the help of the UW Madison Reactor Technology Integration Group (ReTI). MADCOR laboratory focuses, at the same time, on a thermo-mechanical analysis of the system on an application developed on MOOSE environment as well as the adaptation of an existing experimental set-up to produce experimental data on the effect of corrosion on the different maneuvers the control rod will have to perform under a high temperature Helium environment (reduction in sliding velocity, thermal expansion, unintentional blocking of a stage of the control rod).