阶段场格子博尔兹曼模型具有单一的可移动性,用于准不可压缩的两相流
1State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China.
Physical review. E
|March 16, 2024
概括
这项研究引入了改进的格子博尔兹曼模型来模拟二相流动,提高了复杂场景的准确性和稳定性,如大粘度比率.
科学领域:
- 计算流体动力学的流体动力学.
- 多相流量模拟多相流量模拟
- 阶段场建模 阶段场建模
背景情况:
- 准确模拟准不压缩的双相流量对于各种工程应用至关重要.
- 现有的格子博尔茨曼模型面临着可变移动性和大粘度比的挑战.
研究的目的:
- 提出一个改进的格子博尔兹曼模型,用于基于卡恩-希利亚德相场理论的准不可压缩的两相流.
- 在双相流模拟中,提高可变/零流动性和高粘度比率的处理能力.
主要方法:
- 开发了一个格子博尔兹曼模型 (LBE),包括两个部分:一个用于卡恩-希利亚德方程 (CHE),另一个用于准不可压缩的纳维埃-斯托克斯方程 (qINSE).
- 对于CHE的LBE采用了可变/零移动性的自由参数,而对于qINSE的LBE则使用了局部剪速的参数来处理较大的粘度比.
- 结合了水力动力学方程,并通过模拟相位接口捕获,双静止滴和滴滴落下的问题来验证模型.
主要成果:
- 拟用于CHE的LBE在捕获相位接口方面表现出与原始模型相比更高的精度和稳定性.
- 合模型有效地减少了数值散射,并为滴滴动力学和相位分离提供了物理上可接受的结果.
- 成功模拟了具有粘度比高达10^4.4的两相流.
结论:
- 增强的格子博尔茨曼模型为模拟近乎不可压缩的两相流提供了强大而准确的方法,特别是那些具有流体特性显著变化的流体.
- 该模型能够处理较大的粘度比率并保持稳定性,这为流体动力学中更复杂和更现实的模拟提供了可能性.
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