一个特征性的非反射边界低马赫数流量诱导的噪声
Ye Yuan1, Youhong Xiao1, Qiannan Xu2
1College of Power and Energy Engineering, Harbin Engineering University, Harbin 150001, China.
The Journal of the Acoustical Society of America
|July 18, 2025
概括
一个新的低马赫数特征边界条件 (LMCBC) 有效地降低了不可压缩流中的声音反射. 扩展版本PLMCBC和ZLMCBC进一步提高了低马赫数声学的非反射性能.
科学领域:
- 计算流体动力学的流体动力学.
- 声学 声学 在声学上
- 数学方法 数学方法
背景情况:
- 特性边界条件是可压缩流噪声模拟的标准.
- 模拟不可压缩的流量噪声需要非反射边界条件,以避免人工声音波反射.
- 像完美匹配层 (PML) 这样的现有方法在低马赫数模式中存在局限性.
研究的目的:
- 引入和验证低马赫数特征边界条件 (LMCBC) 对于不可压缩的流量诱导噪声.
- 将LMCBC的非反射性能与PML等已知方法进行比较.
- 开发增强的边界条件 (PLMCBC,ZLMCBC) 以提高低马赫数声学模拟的精度.
主要方法:
- 从声学扰动方程 (APE-2) 中导出LMCBC.
- 在OpenFOAM软件中实现LMCBC,用于不可压缩的Navier-Stokes和APE-2计算.
- 使用基准问题和平面波测试案例的验证,具有不同的冲击角度和马赫数.
主要成果:
- 对于不可压缩的流量,LMCBC显示了准确而强大的非反射性能.
- 比较显示LMCBC在特定的低马赫数场景中表现优于或匹配PML和减压层.
- 拟议的区域LMCBC (ZLMCBC) 实现了最低的反射水平,并提高了对波长变化的强度.
结论:
- LMCBC是模拟不可压缩的流量诱导噪声的可行和有效的边界条件.
- 扩展方案,特别是ZLMCBC,为低马赫数流 (Ma=0-0.3) 提供卓越的非反射性能.
- 开发的方法为工程应用中准确的声学模拟提供了增强的工具.
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