A heat recovery ventilation system enables us to control indoor conditions such as ventilation rate,
temperature, relative humidity and pressure difference. These environmental conditions affect indoor radon
Computational fluid dynamics (CFD) is a powerful tool for predicting and visualizing radon content and indoor
air quality and is cost effective in comparison with other methods such as full scale laboratory and gas trace
In this study a mechanically balanced ventilation system and a continuous radon monitor (CRM) were used
to measure the indoor ventilation rate and radon levels. In a numerical approach the FLUENT CFD package
was used to simulate radon entry into the building and effects on indoor air conditions.
The effects of different ventilation rates, indoor temperature and relative humidity on indoor radon
concentrations were investigated in a one family detached house in Stockholm. Results of numerical studies
indicated that changes of ventilation rate, indoor temperature and moisture by means of ventilation systems
have significant effects on indoor radon content. Ventilation rate was inversely proportional to indoor radon
concentration. Minimum radon levels were estimated in the range of thermal comfort, i.e. at 21 and
relative humidity between 50-70%.
The analytical solution was used to validate numeric results at 3 distinct air change rates. Comparisons
between numerical and analytical results showed good agreement but there was poor agreement between
simulations and measurement results due to the short measuring period.
2012. , 10 p.1-10 p.
THE 25TH INTERNATIONAL CONFERENCE ON EFFICIENCY, COST, OPTIMIZATION, SIMULATION AND ENVIRONMENTAL IMPACT OF ENERGY SYSTEMS JUNE 26-29, 2012, PERUGIA, ITALY