An Exploratory Comparison of Local Thermal Responses in Compacted and Uncompacted Magnesium Alloy Chip-Bed Fires

Magnesium alloy chip-bed fires may exhibit different local thermal behaviors depending on the packing conditions. This study compared fires under uncompacted and compacted conditions by evaluating the local temperature, heat flux, and visible flame behavior. The results indicated that the uncompacted bed exhibited high-temperature responses over a broader region, whereas the compacted bed exhibited more localized responses at higher temperatures. Variations were also observed in the spatial distribution, arrival times of the high-temperature responses, and in the temperature-heat flux relationship. These findings indicate that the effect of compaction should be evaluated based on the spatial extent, localization, and temporal characteristics of the local thermal responses, rather than the maximum temperature alone.