LAUSR

For clarifying the combustion behavior of circular ring thin-layer pool fire, a series of experiments with varying pool diameters were carried out. The equivalent pool area of 0.071 m^2 and an initial n-heptane thickness of 10 mm were fixed. Electronic balance, digital camera and K-type thermocouples were used respectively to measure burning rate, flame height as well as centerline temperature. The results show that more burning stages can appear with the increase of the inner and outer diameters of circular ring pool. Fire merging can occur at any one of initial growth, quasi-steady burning with surface boiling, transition to bulk boiling and bulk boiling burning stages, and moreover the maximum burning rate of fire merging is about 3.5 times the one of the ordinary pool fire with same area. The core hollow region plays an important effect in decreasing the burning rate, flame height and fire merging time etc. The evolutions of the characteristic parameters e.g. burning rate, flame height and centerline ...