Coupled In-Rock and In-Drift Hydrothermal Model Study for Yucca Mountain

Temperature, Humidity, and Airflow in the Emplacement Drifts Using Convection and Dispersion Transport Models

“…Comparisons showed good agreement between the results from the monolithic model [8,9] and those from the coupled MF model, configured with equivalent dispersion transport processes along the axial direction of the emplacement drift [12]. The current paper goes beyond the previous MF model configurations of equivalent dispersion.…”

“…The length of the unheated sections are kept at 80 m, the same length used by Birkholzer et al [8,9] in order to evaluate agreements and/or differences caused by transport model components instead of arrangement geometry. It has been pointed out before by Danko et al [12] that the axial moisture transport and the humidity in the emplacement drift are quite sensitive to the length of the unheated sections. The unheated drift sections are connected to the undisturbed and also unheated edges, which provide a dominantly conductive heat sink to the heated portion of the rockmass around the center of the emplacement drift.…”

“…The unheated drift sections are connected to the undisturbed and also unheated edges, which provide a dominantly conductive heat sink to the heated portion of the rockmass around the center of the emplacement drift. This arrangement, described in [12], manifests a strongly 3-D temperature field in and around the drift with cooler temperatures around the drift ends. Likewise, the representative NTCF model, a surrogate model using response functions based on the TOUGH2 thermal-hydrologic porous-media code, is also used unchanged.…”

“…The multi-scale rockmass model is identical to that of previous studies [1,12]. The rockmass surrounds a representative drift in the middle of an emplacement panel.…”

Earth Sciences Division Research Summaries 2006-2007

“…To fully account for 3-D effects, a first model (MF-T2) operates on a scale that encompasses the entire drift plus surrounding ro c k units. In MF-T2, the flow and transport processes in the ro c k mass are simulated with the multiphase, multicomponent simulator TOUGH2, and the in-drift heat and moisture flows are simulated with MULTIFLUX (MF), a lumped-parameter CFD (Computational Fluid Dynamics) code (Danko et al, 2007). MF p rovides an efficient iterative coupling technique for matching the mass and heat transfer between the rock mass and the drift.…”