在旋转的流体环中温度振荡的同步现象和外部强迫的最佳波形
Ippei Oshima1,2, Yoji Kawamura2
1Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan.
Chaos (Woodbury, N.Y.)
|April 8, 2025
概括
在热对流中同步是从任何初始条件实现的,最佳波形显著扩大同步区域. 准确的评估需要分析振荡期统计数据,而不仅仅是差异.
科学领域:
- 流体动力学 流体动力学
- 非线性动力学是一种非线性动力学.
- 热传递是一种热传递.
背景情况:
- 旋转流体环形中的热对流会表现出复杂的同步现象.
- 了解同步对于预测系统行为和稳定性至关重要.
研究的目的:
- 调查移动和振荡热对流的同步.
- 确定准确的同步状态评估的标准.
- 优化波形以扩大同步区域.
主要方法:
- 三维的直接数值模拟.
- 计算相位灵敏度和相位合功能的计算.
- 优化波形,以适应引进范围,速度和工作周期.
主要成果:
- 波形表现出正弦形图案,导致从任何初始条件同步.
- 理论上的同步标准准确地预测了同步区域.
- 50%的最佳工作周期最大限度地提高了12%的引进范围,而不是100%.
结论:
- 同步状态评估需要分析振荡周期的平均值和标准偏差.
- 最佳波形显然会在热对流系统中扩大同步区域.
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