EFFECTS OF SEASON (WINTER AND SUMMER) ON FLAME
TEMPERATURE IN OPEN POOL FIRE

Fire tests were conducted using a one-sixth slice model of a real cask in winter and summer to evaluate the effect of the season on the flame temperature and the thermal integrity of the metal cask. Comparing the maximum and average temperatures of the test model measured in the fire tests conducted in winter and summer, both the maximum and average temperatures were higher in the fire test conducted in summer. That is because in the fire test conducted in summer, the test model received more heat input from the flame. In the fire test conducted in summer, it took longer for the high-temperature flame to transfer inside than the fire test conducted in winter. This is because the temperature of the test model itself was higher due to the higher ambient temperature in summer than in winter, and the thermal resistance was a little greater. In addition, in the fire test conducted in summer, it is estimated that the test model received more heat from the flame and took a little longer to transfer heat to the inside. Accordingly, a more conservative test result can be obtained if the fire test is carried out in the summer than in winter. Therefore, it is desirable to conduct fire tests in summer to evaluate the thermal integrity of the transport cask, if possible. As a result of fire tests conducted in winter and summer, it was evaluated that the metal cask can maintain its thermal integrity under a fire accident condition (800 °C for a period of 30 min).