Research on Early Fire Smoke Movements and Detection Method in Stable Thermally Stratified Environments

The movements of smoldering cotton wick smoke and flaming diesel oil smoke plumes in thermally stratified environments in a small scale enclosure were investigated by experiments and CFD simulations. The reasonably good agreements of the experimental and simulated results indicated that the thermally stratified environments intensified the decreases of the axial temperatures and velocities of a fire smoke plume. The previous integral equation was shown to underestimate the maximum smoke rises, and also unable to explain the differences of the maximum heights of low and high density smoke with the same stratification and outlet conditions. An improved integral equation and an effective detection method were introduced and discussed.