Investigation on thermal feedback and combustion characteristics of wall-attached pool fires with different aspect ratios and orientations induced by sidewall

Abstract

The occurrence of pool fires adjacent to a sidewall poses significant risks. To investigate fire source combustion characteristics and thermal feedback of sidewall-attached fires, experiments involving rectangular heptane pool fires with varying aspect ratios and pool orientation relative to sidewall were conducted. The flame tilting behavior, temperature near sidewall, thermal transfer process and air entrainment effects of rectangular pool fires were studied. The findings show that triangular flame shape in parallel arrangements and flame separation of perpendicular setups attribute to the unbalanced air entrainment near sidewall. Perpendicular pools lead to lower temperatures near sidewall surface caused by flame separation. The mass loss rate (MLR) of parallel pool fires initially decreases with n driven by thermal radiation from the flame. It is followed by an increase due to thermal conduction and thermal radiation through the sidewall, with a threshold value at n = 3. The MLR of perpendicular pools decreases continuously owing to the dominance of total thermal radiation. Finally, based on the air entrainment theory, a quantitative correlation between the flame height and n relative to sidewall is proposed. This is also validated by experimental and previous research data.