消除空间间歇性流动中的流
Björn Hof1, Alberto de Lozar, Marc Avila
1Max Planck Institute for Dynamics and Self-Organisation, Bunsenstrasse 10, 37073 Göttingen, Germany. bhof@gwdg.de
概括
研究人员发现了一种机制,通过将剪切能量输送到流中来放大管道流动中的流. 一个简单的控制目标速度的曲点可以崩的流和relaminarize流.
科学领域:
- 流体动力学 流体动力学
- 流的研究研究流.
- 非线性动力学是一种非线性动力学.
背景情况:
- 管道和通道中的流体运输在自然和工业中无处不在.
- 由于较低的摩擦损失,层状流在能源上是高效的.
- 由于对干扰的敏感性,大多数实用的流动是乱的,即使在中等速度,也会如此.
研究的目的:
- 研究流中的运动和空间分布.
- 揭示了从平均剪切到流的能量转移机制.
- 确定控制策略,以减少流.
主要方法:
- 分析旋动态和空间分布.
- 一个能量放大机制的识别.
- 实施一个控制机制,针对速度的转折点.
主要成果:
- 发现了一种放大机制,将能量从平均剪切转移到乱的.
- 一个简单的控制策略有效地拦截了这种能量转移.
- 激活控制器会立即导致流崩和流量再层化.
结论:
- 流的管道和通道流可以通过针对特定机制来控制.
- 重层化是通过对速度配置文件的有针对性的干预来实现的.
- 这项研究提供了关于控制流体流量效率的见解.
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