分布参数对来自泡集群的声辐射的影响
Fuqiang Deng1, Lingxin Zhang1, Peng Wang1
1State Key Laboratory of Fluid Power and Mechatronic Systems, Department of Engineering Mechanics, Zhejiang University, Hangzhou 310027, China.
Ultrasonics sonochemistry
|September 17, 2024
概括
直接的数值模拟显示,无论泡的大小或位置,泡团的崩时间都相似. 层层的气泡排列产生多个声音脉冲,而不是随机排列发出单个脉冲.
科学领域:
- 水下声学 水下声学
- 流体动力学 流体动力学
- 声波化声学化
背景情况:
- 洞穴噪音是水下声学的一个重要问题.
- 了解来自气泡集群的声辐射是洞穴噪声机制的关键.
研究的目的:
- 研究气泡集群的声波辐射和崩动态.
- 将泡集群的行为与同等单个泡进行比较.
主要方法:
- 对于气泡集群 (20-40%体积分数) 的直接数值模拟 (DNS).
- Ffowcs威廉姆斯-霍金斯 (FW-H) 方法用于远场声压计算.
- 对不同泡大小和位置分布的分析.
主要成果:
- 气泡集群的崩时间对于给定的体积分数是相同的,不论气泡的大小或分布.
- 层层的气泡排列导致层层的崩和多个声音脉冲.
- 随机安排和不同的泡大小对声辐射模式的影响最小,类似于等价泡.
结论:
- 气泡集群崩的动态主要由体积分数控制.
- 声波辐射模式受到泡布局的强烈影响,层层的结构产生明显的多脉冲辐射.
- 频域中的声压水平在 >25%体积分数的气泡集群中趋同,与相当的气泡密切匹配.
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