Numerical generation and analysis of a postulated fuel debris bed in liquid Pb coolant

In the development of Lead Fast Reactors (LFR's) a severe accident that should be considered is the partial or severe core degradation with loss of fuel inventory.  This requires a detailed analysis of the spreading of fuel debris, forming of a debris bed as well as determining how the bed further develops or degrades.  As it is a complex problem, several modern numerical methods may be employed to firstly i) generate a numerical bed, then ii) analyse the flow and heat transfer behaviour of the bed.  As the physical means to conduct experiments of this nature is hazardous, the problem needs to be investigated numerically.

It is proposed that the visiting student familiarises themselves with the proposed numerical code(s), generate a bed using Discreet Element Method (DEM) Lagrangian approach for the modelling of fuel debris particles, analyse the resulting structure porosity and porosity variation to perfrom Computational Fluid Dynamics (CFD) flow simulation using a) the discrete geometry and/or b) a porous medium approach and finally investigate how heat generation may be included in the model.