A viscoplastic approach to corium spreading during a severe nuclear accident

A viscoplastic model for lava is presented, and its use for corium spreading is argued with dimensionless numbers. It describes the tridimensional flow as non-Newtonian and non-isothermal. Using an adaptive finite element method based on C++ library Rheolef, simulations are ran and compared to the VEU7 corium spreading test. A sensitivity analysis on the viscoplastic parameters of corium that are not well-known is conducted. Tridimensional solution of the problem is computed from the bidimensional height-averaged solution.

Automated summary

A viscoplastic model for lava is proposed in this paper, which is applied to the spreading of corium with dimensionless numbers. The model considers the tridimensional flow as non-Newtonian and non-isothermal. Simulations are conducted using an adaptive finite element method based on C++ library Rheolef, and the results are compared with the VEU7 corium spreading test. A sensitivity analysis is also performed on the viscoplastic parameters of corium. The tridimensional solution is computed from the bidimensional height-averaged solution.