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一种用于近似高频声音辐射的方法 - 平面投影雷利积分
Marius Walther1,2, André Gerlach2, Marko Liebler2
1Measurement and Sensor Technology Group, Technische Universität Darmstadt, 64289 Darmstadt, Germany.
The Journal of the Acoustical Society of America
|March 12, 2025
概括
一种新的平面投影雷利积分 (PPRI) 方法为振动表面提供了高效和准确的声音辐射计算. 这种近似方法显著减少了计算的努力和错误,特别是在更高的频率.
科学领域:
- 声学 声学 在声学方面
- 计算力学 计算力学 计算力学
- 数字分析 数字分析
背景情况:
- 从振动表面计算声音辐射往往需要计算密集的基于积分的数值方法.
- 高频率需要增加离散性,导致显著的计算负担.
- 有需要的近似方法,平衡计算效率与高精度.
研究的目的:
- 介绍和评估一种新的近似方法,即平面投影雷利积分 (PPRI).
- 与现有方法相比,评估PPRI的准确性和计算效率.
- 分析PPRI关于表面曲率,频率和距离的性能.
主要方法:
- 平面投影雷利积分 (PPRI) 方法通过将雷利积分应用于2D虚拟平面来近似声辐射.
- 性能评估涉及与可见元素雷利积分和高频边界元素方法 (HFBEM) 的比较.
- 呼吸和振荡球体的分析解决方案作为准确性评估的基准.
主要成果:
- 与可见元素雷利积分和HFBEM相比,PPRI方法显示出更高的准确性.
- 误差随着更大的半径和更高的频率而减少,在比HFBEM小得多的海尔姆霍尔茨数下,误差低于1%,达到1%以下.
- 在评估的方法中,PPRI需要最少的计算时间.
结论:
- 在声音辐射计算中,PPRI方法有效地实现了高精度和计算效率.
- 这种方法为需要精确声学预测且计算成本降低的场景提供了有价值的替代方案.
- 在更高的频率和具有更大的曲率半径的表面上,PPRI的性能特别有利.
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