陀螺作为一种新的方法来抑制流散和减轻诱导的振动
Thomas Berger1, Mohamed Farhat2
1Institute of Mechanical Engineering, École Polytechnique Fédérale de Lausanne, Avenue de Cour 33 Bis, 1007, Lausanne, Switzerland. thomasantoinenicolas.berger@epfl.ch.
Scientific reports
|July 16, 2025
概括
在翼尾端的Gyroid延伸通过破坏卡尔曼形成,显著减少了引发的振动 (VIV). 这项创新可以抑制振动和噪音,而不影响水力动力性能,提供广泛的工程应用.
科学领域:
- 流体动力学和水力动力学
- 机械工程和设计的设计.
背景情况:
- 引发的振动 (VIV) 是水翼船和其他水下结构面临的重大挑战.
- 卡曼旋在潜水艇的尾端散落,会引起振动和疲劳.
- 现有的VIV缓解策略往往会损害水力动力效率.
研究的目的:
- 为了研究一个Gyroid结构的扩展在减轻水翼上的VIV的有效性.
- 为了阐明由Gyroid扩展抑制VIV的流体物理.
- 评估Gyroid延伸对水翼翼的升力和阻力特性的影响.
主要方法:
- 在水流中使用的截断NACA 0009翼机进行实验研究.
- 在高雷诺兹数 (0.6×10^6到2×10^6) 的流量条件下.
- 激光多普勒测速仪用于详细测量唤醒速度.
- 分析表面速度信号和水力动力学力 (升力和阻力).
主要成果:
- 陀螺延伸完全抑制了与VIV相关的扭转锁定现象.
- 平均平方根 (RMS) 表面速度降低了67% (锁定) 和99.5% (锁定).
- 消除Strouhal流失频率峰值并减少宽带噪声激发.
- 状腺延伸会产生沿流和横流的喷气,抑制连贯 vortex 的形成.
- 没有观察到提升力和阻力力的显著变化.
结论:
- 陀螺延伸有效地通过其多孔和曲的结构来防止卡曼 vortex 的形成.
- 这种新的方法可以显著降低VIV和相关噪声,而不会影响性能.
- 这些发现对在航空航天和海洋应用中设计抗VIV结构具有广泛的影响.
相关概念视频
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One of the distinctive characteristics of circular shafts is their ability to maintain their cross-sectional integrity under torsion. In other words, each cross-section continues to exist as a flat, unaltered entity, simply rotating like a solid, rigid slab. To understand the distribution of shearing stress within such a shaft, consider a cylindrical section inside this circular shaft. This section has a length of L and a radius of R, with one end fixed. The radius of the cylindrical section is...
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01:15Thin-Walled Hollow Shafts
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In analyzing a thin-walled hollow shaft subjected to torsional loading, a segment with width dx is isolated for examination. Despite its equilibrium state, this segment faces torsional shearing forces at its ends. These forces are quantitatively described by the product of the longitudinal shearing stress on the segment's minor surface and the area of this surface, leading to the concept of shear flow. This shear flow is consistent throughout the structure, indicating a uniform distribution...
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01:13Circular Shaft - Stresses in Linear Range
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01:16Design of Transmission Shafts
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01:17Magnetic Damping
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