Analysis of thermohydrologic behavior for above-boiling and below-boiling thermal-operating modes for a repository at Yucca Mountain.

摘要: Abstract We report results from a multi-scale thermohydrologic modeling study for two alternative thermal-operating modes the potential repository system recently analyzed by Yucca Mountain Project. These include Higher-Temperature Operating Mode (HTOM), which in localized boiling zone around each emplacement drift, and Lower-Temperature (LTOM), always maintains sub-boiling temperatures throughout repository. The HTOM places all waste packages nearly end to end, making lineal power density greater than LTOM. lower LTOM was achieved placing some farther apart (which larger footprint), through an increased reliance on pre-closure ventilation remove waste-package-generated heat. focus temperature T relative humidity RH at waste-package drift-wall surfaces, in-drift evaporation. In general, are corresponding temperatures, exhibit similar spatial variability have stronger dependence infiltration flux. duration of reduction is HTOM. A major difference between any given value Waste-package LTOM, design, remain below ∼85 °C; absence arising host-rock dryout causes above about 40%. experience higher correspondingly conditions as result dryout. For most area, delays onset gravity-driven seepage compared (as indicated drift wall). Boiling also capillary-driven into granular invert, causing less evaporation invert during first 800–1500 years LTOM; subsequent rates HTOM, due density.