在完全发达的注射条件下,液体喷射器的普遍自由落体定律
M Beneitez1, D Moreno-Boza2, A Sevilla2
1DAMTP, Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WA, United Kingdom.
Physical review letters
|December 15, 2023
概括
我们发现了空气中垂直液体喷射的普遍形状,重力主导粘度. 这种新模型准确地预测了喷气半径,与以前的理论不同.
科学领域:
- 流体动力学 流体动力学
- 液体的物理 液体的物理
- 空气动力学 在空气动力学.
背景情况:
- 了解液体喷射的行为在各种科学和工程领域至关重要.
- 以前的模型,如马里奥特定律,在描述特定条件下的喷气动力学方面存在局限性.
研究的目的:
- 为空气中垂直的液体喷流得出一种通用形状.
- 为喷射半径提供基于流体动力学原理的分析解决方案.
- 通过实验数据验证理论模型.
主要方法:
- 开发了一个使用理想流与旋流理论的分析解决方案.
- 假设粘性力比重力要小得多.
- 为了简化,忽略了表面张力.
主要成果:
- 为缩放的喷气半径推导出一个通用方程:Rj = [(1+Z/4)1/2 - (Z/4)1/2]1/2.2.
- 该方程将喷射半径 (Rj) 与垂直距离 (Z) 相关,以引力长度 (l<0xE1><0xB5><0xA2>) 进行缩放.
- 来自长时间注射器的实验数据与新的理论预测有很好的一致性.
结论:
- 由此衍生的通用形状为垂直液体喷流提供了更准确的描述.
- 这种新模式挑战并改进了像马里奥特法这样的现有法律.
- 这一发现对理解和预测空气中的液体喷流行为有意义.
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