Radon exhalation from phosphogypsum building boards: symmetry constraints, impermeable boundary conditions and numerical simulation of a test case
| Autor: | José Antonio Rabi, Nivaldo Carlos da Silva |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Computer simulation
Construction Materials Health Toxicology and Mutagenesis chemistry.chemical_element Mineralogy Radon Phosphogypsum Building material Phosphorus General Medicine Mechanics engineering.material Pollution Calcium Sulfate Symmetry (physics) chemistry Bounded function engineering Environmental Chemistry Boundary value problem Transient (oscillation) Waste Management and Disposal Geology |
| Zdroj: | Journal of environmental radioactivity. 86(2) |
| ISSN: | 0265-931X |
| Popis: | Comprehensive understanding of (222)Rn exhalation from phosphogypsum-bearing building material and its accumulation in indoor air is likely to rely on numerical simulation, particularly if transient effects, three-dimensional domains and convection are to be included and investigated. Yet, experimental data and analytical results are helpful (if not crucial) as far as validation is concerned. Having in mind computational code simplicity and in the light of a recent experimental and theoretical report on (222)Rn release from phosphogypsum boards for housing panels, this paper presents and discusses an alternative testing set-up and the corresponding boundary conditions, namely one side of the panel bounded by impermeable wall. Although this is a new facility to be tested, the resultant steady-state one-dimensional diffusion-dominant analytical solution is shown to match the counterpart deduced in the aforementioned previous report, despite it relaxes the constraint of symmetry about the phosphogypsum board centerline, which is inferred in that prior experimental scenario. In addition, numerical results are conducted for a diffusion-dominant two-dimensional time-varying test case concerning (222)Rn accumulation in a closed chamber having an exhaling phosphogypsum board tightly placed at one wall. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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