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Updated: Jun 17, 2025

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Magnetically Induced Rotating Rayleigh-Taylor Instability
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通过对点轨迹的统计分析,确定控制热声学不稳定的最佳位置
C P Premchand1, Abin Krishnan2, Manikandan Raghunathan2
1Department of Aerospace Engineering, Indian Institute of Technology Bombay, 400076 Mumbai, India.
Chaos (Woodbury, N.Y.)
|August 14, 2024
概括
拉格朗连贯结构 (LCS) 为燃烧噪声提供了被动控制. 通过准流动力学,这种方法在热声不稳定期间显著降低了声音振幅.
科学领域:
- 流体动力学 流体动力学
- 声学 声学 在声学方面
- 燃烧科学是一种科学.
背景情况:
- 热声学不稳定性会在燃烧器中产生音调的声音.
- 了解流动动态对于降低噪声至关重要.
研究的目的:
- 开发一种使用LCS进行音调降低的被动控制框架.
- 为了研究流动动力学变化后控制.
主要方法:
- 使用的拉格朗连贯结构 (LCS) 框架.
- 采用动态模式分解用于流场分析.
- 通过注入二次空气来实现被动开环控制.
主要成果:
- 确定了主导的声频区域和剪切层动态.
- 在剪切层中跟踪的位点,以实现最佳的控制准.
- 观察到与燃烧器轴相平行的剪切层偏移后控制.
结论:
- 使用LCS的被动控制有效地降低了声音振幅.
- 剪切层的偏移防止了旋的包裹和墙壁的碰撞.
- LCS框架为减噪提供了对流动动态的洞察力.
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