Experimental analyses by SIMMER-III on duct-wall failure and fuel discharge/relocation behavior

Abstract

This paper describes experimental analyses using SIMMER-III and -IV, which are respectively two- and three-dimensional multi-component multi-phase Eulerian fluid-dynamics codes, for the purpose of integral code validation. Two topics of key phenomena in core disruptive accidents of sodium-cooled fast reactors are presented in this paper: duct-wall failure and fuel discharge/relocation behavior. To analyze the duct-wall failure behavior, the SCARABEE BE+3 in-pile experiments were selected. The SIMMER-III calculation was in good agreement with the overall event progression; which was characterized by coolant boiling, clad melting, fuel failure, molten pool formation, duct-wall failure, etc.; observed in the experiment. The CAMEL C6 experiment investigated the fuel discharge and relocation behavior through a simulated control rod guide tube, which is important in evaluating the neutronic reactivity. SIMMER-IV well simulated fuel-coolant interaction, sodium voiding, fuel relocation behavior observed in the experiment. These experimental analyses indicated the validity of the SIMMER-III and -IV computer code for the duct wall failure and fuel discharge/relocation behavior.

Keywords

• sodium-cooled fast reactor
• core disruptive accident
• multi-phase flow
• simulation code
• simmer-iii
• wall failure
• fuel discharge
• fuel relocation