Integrated Numerical Simulation with Fungal Spore Deposition and Subsequent Fungal Growth on Bathroom Wall Surface

Abstract

Fungal contaminations in indoor environment are recognized as one of the serious problem in terms of health and aesthetic impact. Large numbers of studies have shown an association between the health risk of fungal contamination. Residence in houses and fungal growth is well known to be strongly related to various indoor environmental parameters and hence the development of a comprehensive prediction method for fungal contamination is needed for healthy indoor environmental design. This research focused on the fungal growth problems in residential bathroom where the temperature and humidity can become relatively high. This paper reports the procedure and results of numerical simulations of fungal contamination. The simulation was incorporated with flow field, temperature/humidity distribution, which was used to predict fungal spore dispersion/deposition in bathroom space and subsequent non-uniform distribution of fungal growth on wall surfaces. Fungal spores transportation was analyzed by Lagrangean approach. For fungal growth phenomenon, the reaction-diffusion model that reproduces morphological colony formation of fungi was adopted. By continuously executing these numerical analyses, fungal spore deposition and subsequent fungal growth on wall surfaces was demonstrated for two targeted representative ventilation rate in normal bathroom condition.

Keywords

Fungi Reaction diffusion model Hygrothermal transfer Bathroom Lagrangean particle tracking Deposition CFD

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