滴的加热和蒸发:简单和先进的模型
Dmitrii V Antonov1,2,3, Elena M Starinskaya2,4, Sergei V Starinskiy2,4,5
1Heat and Mass Transfer Laboratory, National Research Tomsk Polytechnic University, Tomsk 634050, Russian Federation.
Langmuir : the ACS journal of surfaces and colloids
|January 29, 2024
概括
式滴水加热和蒸发的新型号提供了更高的精度. 先进的2D模型捕捉空间热分布,而更简单的1D和2D模型为滴滴半径和温度变化提供了良好的近似值.
科学领域:
- 热力学是一种热力学.
- 流体动力学 流体动力学
- 热传递是一种热传递.
背景情况:
- 精确的模拟状滴水的行为对于理解热量和质量转移过程至关重要.
- 现有的一维 (1D) 模型往往过于简化了液滴内的热量分布.
- 需要更复杂的模型来解释热传输的空间变化.
研究的目的:
- 开发和验证新的二维 (2D) 模型,用于式滴水加热,冷却和蒸发.
- 将高级2D,简单2D和简单1D模型的预测能力与实验数据进行比较.
- 评估不同模型对于预测滴滴半径和表面温度动态的适用性.
主要方法:
- 在COMSOL多物理中开发了一个先进的2D模型,使用数值解决方程 (质量,动量,蒸汽质量分数,能量) 的数值解决方案.
- 创建了简单的2D和1D模型,假设截断的球状滴状形状,并通过数值 (简单的2D) 或通过数值 (1D) 实现的分析解决热传导方程.
- 在298.15K和大气压下测试状水滴 (2.25.2μL) 的实验数据对模型预测进行了验证.
主要成果:
- 这三种模型 (先进的2D,简单的2D,1D) 都显示出对正常化滴滴半径平方的实验数据的良好一致,支持对这个参数使用简单的1D模型.
- 先进的2D模型准确地预测了平均表面温度的时间依赖性,与实验观测密切匹配.
- 简单的2D和1D模型成功地捕获了最初的快速下降,随后是平均表面温度的逐渐增加,与实验结果一致.
结论:
- 开发的先进的2D模型通过考虑空间热分布,提供了更准确的液滴加热和蒸发的表示.
- 推使用简单的1D模型来预测滴滴半径变化,因为它的准确性和简单性.
- 简单的2D和1D模型为表面温度动态提供了宝贵的见解,特别是最初的冷却和随后的变暖阶段.
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