弥合了环状和环状声谱之间的差距
Tiemo Pedergnana1, Alessandro Orchini2, Jonas Moeck3
1CAPS Laboratory, Department of Mechanical and Process Engineering, ETH Zürich, Zürich, Zürich 8092, Switzerland.
The Journal of the Acoustical Society of America
|March 22, 2024
概括
本研究分析了燃气轮机燃烧器中的热声学不稳定性,弥合了环形和形设计之间的差距. 研究结果揭示了几何变化如何影响声学模式,有助于预测燃烧不稳定性.
科学领域:
- 燃烧的动态 燃烧的动态
- 声学不稳定性的声音不稳定性
- 气力轮机工程 气力轮机工程
背景情况:
- 热声学不稳定性在燃气轮机燃烧器中至关重要,现有的文献区分环状和式环状结构.
- 现实世界中的燃烧器经常呈现混合几何形状,需要一个更普遍的理解超越了这两个极端.
- 燃烧器元素之间的合强度受轴间距的影响,在不稳定现象中起着关键作用.
研究的目的:
- 为了研究理想化的可变几何形状的状燃烧室的声谱.
- 分析调整轴间距如何影响合强度和声学模式.
- 为了弥合纯环形和环形燃烧器配置之间的理解.
主要方法:
- 基于布洛赫波理论的两个理论模型的开发.
- 使用赫尔姆霍尔茨方程的有限元模拟来验证理论模型.
- 对各种轴间隙大小的声谱进行分析,从孤立的到完全开放的环状系统.
主要成果:
- 演示了随着间隙的增加而使环状腔的亚齐穆斯模式转化为自身模式.
- 展示了不同的间隙大小允许从环形到环形声学行为的过渡.
- 确定在特定频率以下的声学模式可以通过整个几何频谱的轴向和定向模式顺序进行分类.
结论:
- 该研究提供了一个统一的框架,用于分析更广泛的燃气轮机燃烧器几何形状中的热声学不稳定性.
- 了解轴间隙距离的影响对于预测和减轻燃烧不稳定性至关重要.
- 开发的模型和分类方案为燃气轮机设计和优化提供了有价值的工具.
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