Definition and Sensitivity Analysis of a CFD Model for the Study of Radon Entry and Accumulation in Buildings

Abstract

Within the framework of a research project funded by the Spanish Nuclear Safety Council, two different models will be developed to allow the study of radon entry and accumulation in buildings located in different regions of potential risk. The final use will be aimed at the prediction of radon entry rates according with the levels of available information about buildings and environmental parameters. In addition, they should be able to predict the reductions achieved by implementing different types of mitigation solutions. One of them will be developed using the finite element analysis software COMSOL MULTIPHYSICS. This paper presents the first phase of the project, describing the fundamentals of the model and a sensitivity study on some of the parameters it incorporates: radon levels in the ground and soil permeability; envelope conditions in terms of porosities, permeabilities, diffusion coefficients, discontinuities; environmental parameters such as pressure conditions, indoor and outdoor temperature, winds, moisture content of the ground. The results and the analysis of their feasibility of application will be compared later with the second model developed with the STELLA software. In a second phase, both models will be compared and calibrated using the monitored data from two real buildings located in areas with high radon exhalation potential.