Forest fire propagation simulations for a risk assessment methodology development for a nuclear power plant

Okano, Yasushi; Yamano, Hidemasa   

As a part of a development of risk assessment methodology on a forest fire as an external hazard, potential challenges to safety function and structural integrity of a nuclear power plant are investigated. Forest fire propagation simulations are performed by using FARSITE simulator to evaluate intensity and key parameters related to "heat" and "flame" effects. Forest fire propagation simulations were performed "with/without prevailing wind" and "high/low of ambient temperature and relative humidity" The study indicates that fireline intensity and reaction intensity are sensitive to prevailing wind and relative humidity, and not to ambient temperature. The maximum reaching height of a flame on a canopy top is close to the range of power line height and a loss of offsite power is recognized as a possible subsequent event during the forest fire.