<p>Pool fires are one of the most common types of fires. This study experimentally investigates the mass loss rate and flame heights of heptane pool fires dominated by conduction or convection under different atmospheric pressures and aspect ratios. In terms of mass loss rate, the results show that the mass loss rate of the pool fires dominated by conduction does not change significantly with the change of pressure (except for the aspect ratio being 8). However, the mass loss rate of pool fires dominated by convection significantly increases 20–40% with the increase of pressure. The reason of mass loss rate increasing with pressure is explained in detail. In terms of flame heights, the correlation between the dimensionless flame height (<InlineEquation ID="IEq1"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10973_2025_14244_Article_IEq1.gif" Format="GIF" Height="19" Rendition="HTML" Resolution="72" Type="Linedraw" Width="48" /> </InlineMediaObject> <EquationSource Format="TEX">$Z_{\rm f} /D^{}$</EquationSource> <EquationSource Format="MATHML"><math> <mrow> <msub> <mi>Z</mi> <mi mathvariant="normal">f</mi> </msub> <mo stretchy="false">/</mo> <mmultiscripts> <mi>D</mi> <mrow /> <mrow> <mrow /> <mo>∗</mo> </mrow> </mmultiscripts> </mrow> </math></EquationSource> </InlineEquation>) and dimensionless heat release rate (<InlineEquation ID="IEq2"> <InlineMediaObject> <ImageObject Color="BlackWhite" FileRef="10973_2025_14244_Article_IEq2.gif" Format="GIF" Height="21" Rendition="HTML" Resolution="72" Type="Linedraw" Width="23" /> </InlineMediaObject> <EquationSource Format="TEX">$\dot{Q}^{}$</EquationSource> <EquationSource Format="MATHML"><math> <mmultiscripts> <mover accent="true"> <mi>Q</mi> <mo>˙</mo> </mover> <mrow /> <mrow> <mrow /> <mo>∗</mo> </mrow> </mmultiscripts> </math></EquationSource> </InlineEquation>) for different atmospheric pressures and aspect ratios is proposed. At the same time, the relationship between flame height and air entrainment coefficient is established, based on the relationship between air entrainment coefficient and atmospheric pressure obtained from previous work. This work can help to understand the evolution of fire dynamics and facilitate risk assessment for the early stage of the pool fires at low pressure.</p>

An analysis of combustion characteristics of rectangular pool fires dominated by convection under different atmospheric pressures and aspect ratios

期刊论文
发表日期：

2025年4月26日

查看全文

Yongzheng Yao,
Ziyang Xia,
Yiyuan Wang,
Luyao Tan,
Fei Ren,
Qiang Wang

摘要

Pool fires are one of the most common types of fires. This study experimentally investigates the mass loss rate and flame heights of heptane pool fires dominated by conduction or convection under different atmospheric pressures and aspect ratios. In terms of mass loss rate, the results show that the mass loss rate of the pool fires dominated by conduction does not change significantly with the change of pressure (except for the aspect ratio being 8). However, the mass loss rate of pool fires dominated by convection significantly increases 20–40% with the increase of pressure. The reason of mass loss rate increasing with pressure is explained in detail. In terms of flame heights, the correlation between the dimensionless flame height ( $Z_{\rm f} /D^{*}$ $Z_{f} / D^{*}$ ) and dimensionless heat release rate ( $\dot{Q}^{*}$ ${\dot{Q}}^{*}$ ) for different atmospheric pressures and aspect ratios is proposed. At the same time, the relationship between flame height and air entrainment coefficient is established, based on the relationship between air entrainment coefficient and atmospheric pressure obtained from previous work. This work can help to understand the evolution of fire dynamics and facilitate risk assessment for the early stage of the pool fires at low pressure.