为多种物种和反应流扩展多克的动量潜力理论
Raffaele D'Aniello1, Mario Casel2, Karsten Knobloch2
1Institute of Propulsion Technology-Engine Acoustics, German Aerospace Center (DLR), Berlin 10625, Germany.
JASA express letters
|February 27, 2024
概括
这项研究将动量潜力理论扩展到复杂的流量,识别了流量波动的新来源. 一个新的模型将近场源与燃烧室中远场声力连接起来.
科学领域:
- 流体动力学 流体动力学
- 声学 声学 在声学方面
- 燃烧方式 燃烧方式
背景情况:
- 杜克的动量潜力理论为分析流体流动波动提供了一个框架.
- 了解燃烧室的噪声产生对于效率和排放控制至关重要.
研究的目的:
- 为了将动量潜力理论扩展到多化学成分,反应性,时间静止的波动流.
- 开发一个时间平均模型来预测燃烧室辐射的声力.
主要方法:
- 这是Doak的动量潜力理论的延伸.
- 在动量波动和度中识别与混合物相关的成分.
- 开发一个时间平均模型,将近场源与远场声力联系起来.
主要成果:
- 确定了动量波动和度的新混合物相关成分.
- 开发了一个模型,将旋转,声学,热和组成的近场源与辐射的声力联系起来.
- 该模型提供了燃烧室噪声的更一般的描述.
结论:
- 扩展理论准确地描述了复杂的流体现象.
- 开发的模型为分析燃烧产生的噪音提供了一个全面的工具.
- 这项工作促进了对反应性流动中的流体动力学和声学的理解.
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