使用欧勒尔-拉格兰方法对旋转流中的洞穴激增特征进行多层次调查
Ziyang Wang1, Demin Liu2, Bin Ji3
1State Key Laboratory of Hydroscience and Engineering, Department of Energy and Power Engineering, Tsinghua University, Beijing 100084, China; Beijing Key Laboratory of CO(2) Utilization and Reduction Technology, Tsinghua University, Beijing 100084, China.
Ultrasonics sonochemistry
|July 15, 2025
概括
研究了旋转流中的水力动力空化 (HC) 激增. 减少化数和旋转数会改变结构和频率,泡反弹会加剧压力波动.
科学领域:
- 流体动力学 流体动力学
- 多相流的流量是多相的.
- 洞穴物理学的洞穴物理
背景情况:
- 在流体机械中,随着旋转的水力动力空化 (HC) 激增普遍存在.
- 了解其不稳定的特性对于工程应用至关重要.
研究的目的:
- 在具有旋转流量的扩散器中研究HC激增的不稳定特性.
- 分析化数和旋转数对冲浪动态的影响.
主要方法:
- 采用双向合欧勒尔-拉格兰治多尺度化模拟方法.
- 与实验数据对比验证的模拟结果.
- 进行了空腔体积和压力波动的综合频谱分析.
主要成果:
- 成功地重现了HC激增的准周期性生长,脱落和碎片化.
- 减少化数量增加了轴对称结构长度和下游分解点.
- 减少旋转数量加剧了螺旋结构的旋转和扭曲.
- 气泡表现出受逆流影响的螺旋运动.
- 洞穴流失和旋绳运动频率在洞穴和旋主导的流动之间有所不同.
- 泡反弹显著增加了中高频压力波动.
- 化数量的减少加剧了化--回流相互作用.
- 旋转数量的减少增加了流量大小,而空洞化加剧了流量波动.
结论:
- 多尺度化模型准确地捕获了HC波浪动态.
- 化数和旋转数是影响冲浪行为和流量结构的关键参数.
- 在旋转的流动中,洞穴--回流相互作用至关重要.
- 气泡动力学显著影响压力波动.
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