什么决定了喷气式飞机的破裂长度?
Stefan Kooij1, Daniel T A Jordan2, Cees J M van Rijn1
1University of Amsterdam, Van der Waals-Zeeman Institute, Science Park 904, Amsterdam, The Netherlands.
Physical review letters
|December 5, 2025
概括
由安格斯特罗姆尺度的热噪声驱动的热毛细血管波量化解释了毛细血管喷气破裂. 这一发现适用于各种实验条件,挑战了关于干扰源的先前假设.
科学领域:
- 流体动力学 流体动力学
- 表面科学是一门学科.
- 热力学是一种热力学.
背景情况:
- 毛细管喷射断裂传统上归因于外部干扰,如噪音,流或喷嘴缺陷.
- 表面干扰的指数增长是控制喷气分解成滴滴的假定机制.
- 这些初始干扰的确切起源和规模仍然是流体动力学的关键问题.
研究的目的:
- 调查毛细管喷流中初始表面干扰的根本原因.
- 为了确定热波动是否可以作为喷气破裂的主要驱动因素.
- 通过一系列实验参数验证喷气破裂的新模型.
主要方法:
- 在各种喷嘴类型中对喷气直径,速度和流体特性进行实验操纵.
- 观察到的初始干扰与热毛细管波理论的预测进行了定量比较.
- 实验数据与先前的分子动力学模拟和对纳米网络的随机水力学计算的整合.
主要成果:
- 最初的喷气干扰在数量上与安格斯特罗姆尺度上的热毛细血管波相一致.
- 不同的喷嘴类型,形状或粗度没有观察到断裂长度的显著变化.
- 热干扰模型成功地预测了喷气破裂长度超过4个数量级的实验,和7个数量级包括先前的模拟.
结论:
- 热噪声,表现为安格斯特罗姆尺度的热毛细血管波,被确定为毛细血管喷气破裂的主要驱动因素.
- 这些发现挑战了外部噪音,流或喷嘴缺陷的必要性,作为喷气式破裂的唯一发起者.
- 基于热波动的统一模型为各种规模的喷气破裂现象提供了强有力的解释.
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