改进的基于相场的晶格博尔兹曼模型,用于蒸发的液体气体流
1Xi'an Jiaotong University, State Key Laboratory for Strength and Vibration of Mechanical Structures, Shaanxi Key Laboratory of Environment and Control for Flight Vehicle, School of Aerospace Engineering, Xi'an 710049, China.
Physical review. E
|October 21, 2025
概括
这项研究引入了一种改进的相场格子博尔兹曼模型,用于蒸发的双相流中传热. 该模型准确地模拟了由蒸汽度驱动的蒸发,显示特定术语被省略时的偏差为12.2%和52.1%.
科学领域:
- 计算流体动力学 计算流体动力学
- 热力学是一种热力学.
- 阶段过渡 阶段过渡
背景情况:
- 在许多工程应用中,精确模拟具有相变的双相流量至关重要.
- 现有的模型可能无法完全捕捉热传递和相变现象 (如蒸发) 的复杂相互作用.
- 格子博尔茨曼法 (LBM) 为模拟复杂的流体动力学提供了一个多功能框架.
研究的目的:
- 介绍一个改进的基于艾伦-卡恩的相场格子博尔兹曼模型,用于模拟蒸发的双相流中的热传输.
- 使用克劳西乌斯-克莱佩隆相关性将蒸汽度和温度场结合起来.
- 通过数值测试验证模型的准确性,并调查模型关键参数的影响.
主要方法:
- 开发了一种增强的相场格子博尔兹曼模型,使用速度,相位,温度和蒸汽度的四个分布函数.
- 通过Clausius-Clapeyron方程将蒸汽度和温度场结合起来.
- 一维 (1D) 斯蒂芬流和二/三维 (2D/3D) 滴滴蒸发的数值模拟.
主要成果:
- 改进的模型与对蒸发现象的理论预期有很好的一致性.
- 进行了蒸发驱动模式 (温度与蒸汽度梯度) 的比较.
- 研究了体积膨胀率术语 (F_β) 和体积特异性热梯度术语 (T_α) 的影响,揭示了当T_α被遗漏时 (52.1%) 与F_β遗漏 (12.2%) 相比显著的偏差.
结论:
- 基于Allen-Cahn的相场格子博尔兹曼模型是模拟热传输双相流中的蒸发的可行工具.
- 界面上的蒸汽度是蒸发的关键驱动因素,其准确的建模是必不可少的.
- 该模型的灵敏度分析强调了包括T_α等特定术语在准确预测中的重要性,特别是在像1DStefan流这样的场景中.
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