Výzkumné centrum: Pokročilé sanační technologie a procesy

Thermomechanical simulations with parallel computer codes

  • numerical prediction of heat dissipation from the repository (objective fo minimize the temperature)
  • stresses in rock and buffer due to thermal expansion
  • computationally demanding problems: large size, long time, details important ... need of parallel computing

The results are obtained in cooperation with Institute of Geonics, Academy of Sciences of the Czech Republic, Ostrava (UGN). We present a model solution of heat conduction and stress field around the repository.

The problem characteristics:

  • disposal boreholes, galleries and canisters (packagings) dimensions, as well as the waste heat production according to the Czech reference repository project
  • reference physical parameters of steel, bentonite and granite
  • sample of the repository structure is modeled, using symmetry assumption
  • domain dimensions 31.62 x 58.0 x 99.77 m

The numerical parameters:

  • discretisation with structured hexahedral mesh, 145 x 105 x 50 nodes, 761250 degrees of freedom for the heat conduction, 2283750 d.o.f. for the elasticity problem
  • simulation time 200 years, automatic time stepping, beginning at 0.0008yrs, ending at 13.1072yrs

Computer equipment for parallel simulations at UGN:

  • workstation IBM xSeries 455 (symmetric multiprocessor – SMP, 8 processors) with 64-bit processors Intel Itanium2 1.3 GHz
  • PC cluster THEA with 8 computer nodes AMD Athlon 1.4 GHz, 1.28 GB RAM.
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Global FEM mesh          Mesh detail at the disposal place   


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Temperature distribution at the time 14 years (maximum) – various cross-sections and a detail.
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Shear stress intensity