通过横向移动的波浪来抑制墙壁流
1Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. Division of Applied Mathematics, Brown University, Providence, RI 02912, USA.
Science (New York, N.Y.)
|May 20, 2000
概括
在围墙流动中产生的流被横向移动的波压制,消除了围墙附近的条纹并减少了剪切应力. 这种高效的方法使用电磁用于盐水应用中的激发.
科学领域:
- 流体动力学 流体动力学
- 控制流的控制流.
- 应用电磁学应用电磁学
背景情况:
- 墙壁中的流会产生很大的阻力和能量损失.
- 控制近壁流对于提高各种工程应用的效率至关重要.
- 现有的流控制方法通常在效率或有效性方面存在局限性.
研究的目的:
- 为了研究使用横向移动波的流产生的抑制.
- 分析这种波对近壁条纹和剪切应力的影响.
- 展示一种实用且高效的诱导移动波的方法.
主要方法:
- 直接数值模拟 (DNS) 用于建模围绕墙壁的流.
- 流动可视化被用来观察近墙结构的行为.
- 在粘性亚层内限制的 spanwise 力量在理论上和实验上被应用.
- 电磁被用来在盐水中有效地产生移动波激发.
主要成果:
- 直接的数值模拟证实,横向移动的波压抑了流的产生.
- 流动可视化显示了近壁条纹的消除,与其他方法相比,这是一个独特的结果.
- 这样可以显著降低墙壁剪切应力.
- 移动波是有效地由高效率的电磁产生的跨度力诱导的.
结论:
- 横向移动的波浪提供了一种新且有效的方法来抑制流.
- 消除靠近墙壁的条纹导致大幅减少阻力.
- 电磁阵列为在真实世界应用中实施这种控制策略提供了一种高效和实用的手段,例如盐水流.
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