Paper presented at the 6th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 30 June - 2 July, 2008.
This paper is devoted to the thermal and economic
aspects involved in the design and conception of a repository
for High Level long-lived (HLLL) radioactive waste. The
design under consideration is a deep geological disposal in
argillite. The French National Radioactive Waste Management
Agency (ANDRA) is in charge of the design and building of
the repository. The dimensioning repository design has to meet
a thermal criterion to prevent any damage on the argillite and
account for the compactness of the disposal underground
installation to limit the cost. In the first stage, a description of
the ANDRA design, followed by the development of its 3D
modelling are presented. Then, a methodology to optimise the
repository design is carried out in order to determine the best
concept dimensioning. Afterwards, an additional investigation
of a further optimisation focuses on the reduction of the
container steel thickness, the associated analyses show that two
antagonist effects (geometrical and thermal effects) compete
with respect to the economical optimisation of the concept.