| 引用本文: | 程崇律,张相冬,孔凡夫,单聪慧,徐宝鹏.液相对流运动对中等尺度池火燃烧速率的影响[J].哈尔滨工业大学学报,2023,55(1):39.DOI:10.11918/202204037 |
| CHENG Chonglü,ZHANG Xiangdong,KONG Fanfu,SHAN Conghui,XU Baopeng.Effect of liquid phase convective motion on the mass burning rate of medium scale pool fires[J].Journal of Harbin Institute of Technology,2023,55(1):39.DOI:10.11918/202204037 |
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| 摘要: |
| 为分析液相对流运动对中等尺度池火燃烧速率的影响,对池火的液相区域进行研究。采用基于气液双向耦合的三维数值模型对池火进行预测,使用大涡模拟方法求解气相区域；通过直接数值模拟求解液相流动,同时考虑浮力效应和马兰戈尼效应；使用共轭传热方法及蒸发模型求解气液两相间的传热传质。用不同燃油池直径、燃油厚度以及燃油种类的池火实验对模型进行验证。研究结果表明:提出的模型能够准确预测中等尺度池火的燃烧速率,预测误差低于3%；在池火发展阶段,忽略马兰戈尼效应和浮力效应导致液相最大流速下降34.3%,液面温差增大70.1%,燃烧速率预测误差增加11.2%；在池火稳定燃烧阶段,浮力效应及马兰戈尼效应对瞬时燃烧速率的影响较小；随着油池直径的增加和深度的降低,浮力效应对燃烧速率的影响逐渐降低；考虑薄层油池液面的下降过程因素能够降低19.2%的燃烧速率预测误差。数值模拟中,考虑液相对流运动及液面下降过程有助于提高中等尺度池火燃烧速率的预测精度。 |
| 关键词: 燃烧速率 池火 大涡模拟 马兰戈尼效应 浮力效应 |
| DOI：10.11918/202204037 |
| 分类号:TQ038.3 |
| 文献标识码:A |
| 基金项目: |
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| Effect of liquid phase convective motion on the mass burning rate of medium scale pool fires |
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CHENG Chonglü,ZHANG Xiangdong,KONG Fanfu,SHAN Conghui,XU Baopeng
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(College of energy and power,Dalian University of Technology,Dalian 116024,China)
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| Abstract: |
| To investigate the effect of liquid phase convective on the mass burning rate of medium scale pool fires, the liquid phase of pool fires was studied. A 3-D numerical model based on gas-liquid two-way coupling was used to model the pool fire. The gas phase and liquid phase were solved by large eddy simulation and direct numerical simulation respectively, taking into account buoyancy and Marangoni effects in the liquid phase. The heat and mass transfer between the two phases were calculated using a conjugate heat transfer method and an evaporation model. The proposed model was then validated by three pool fire experiments with different fuel sizes, fuel thicknesses and fuel types. The research results showed that the proposed model could accurately predict the mass burning rate of medium scale pool fires with a prediction error of less than 3%; in the development stage of pool fires, ignoring the Marangoni effect and buoyancy effect led to the maximum liquid velocity increased by 34.3%, the liquid surface temperature difference increased by 70.1% and the mass burning rate prediction error increased by 11.2%. In the stable combustion stage of pool fires, the buoyancy effect and the Marangoni effect had little influence on the instantaneous mass burning rate. With the increase of the diameter and the decrease of the depth of pools, the effect of the buoyancy effect on the combustion rate gradually decreased; Considering the descending process of the liquid level of thin-layer pool could reduce the prediction error of the combustion rate by 19.2%. In the numerical simulation, considering the liquid phase convective motion and the liquid surface drop process contributed to improve the prediction accuracy of the mass burning rate of medium scale pool fires. |
| Key words: mass burning rate pool fire large eddy simulation Marangoni effect buoyancy effect |
