形状优化的声学元级,用于在强烈的热效应下异常折射
Anton Melnikov1, Sören Köble2, Severin Schweiger2
1Fraunhofer Institute for Photonic Microsystems IPMS, Dresden, Germany. anton.melnikov@tum.de.
Scientific reports
|November 3, 2024
概括
这项研究提出了用于操纵MHz频率的声音波的新型微声学元级. 设计考虑了热粘性损失,使得像超声波成像等应用程序的精确声学聚焦.
科学领域:
- 声学和材料科学 声学和材料科学
- 超材料是指一种超材料.
- 声学元材料是一种声学元材料.
背景情况:
- 微声学元格线为平面声学镜头和超声波成像等应用提供了对声波前线的被动控制.
- 双光子聚合使MHz空载超声波元级的微结构能够精确地制造.
- 将元格级缩小到MHz频率引入了显著的热粘性损失,使设计复杂化.
研究的目的:
- 提出和设计能够折射正常撞击波向-2MHz的-35°的微声学元格.
- 调查微声超级分级的单体和双体元原子设计.
- 通过实验验证拟议的设计和制造技术.
主要方法:
- 采用了采用线性化纳维埃-斯托克斯方程的形状优化技术来解释热粘效应.
- 利用双光子聚合来精确制造微声学元格.
- 使用电容微机超声波传感器和从1.8到2.2MHz的光学麦克风,实验评估了化性能.
主要成果:
- 成功设计了微声学元级,包括一种新的两体元原子几何,可在-2MHz的-35°中折射声音.
- 实验结果验证了拟议的metagrating设计的性能.
- 证实了用于制造微观声学元材料的双光子聚合物的有效性.
结论:
- 该研究成功地展示了微声学元级的设计和制造,用于在MHz频率上精确的声学操纵.
- 开发的形状优化方法有效地结合了对于高频声学元材料设计至关重要的热效应.
- 这些发现为先进的声学设备铺平了道路,包括改进的超声波成像和平面声学镜头.
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