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剪切稀释液体喷气的初级原子化:一个直接的数值模拟研究.
Marianne Abdelsayed1, Elias Trautner2, Jakob Berchtenbreiter2
1University of the Bundeswehr Munich, Department of Aerospace Engineering, Institute of Applied Mathematics and Scientific Computing, Werner-Heisenberg-Weg 39, 85577, Neubiberg, Germany. marianne.abdelsayed@unibw.de.
Scientific reports
|October 12, 2024
概括
研究剪切稀释液体喷流揭示了在初级原子化过程中,界面上的流体行为显著影响滴滴大小和形状. 然而,核心喷气速度和体积分数统计数据基本上没有受到影响.
科学领域:
- 流体动力学 流体动力学
- 多相流程 多相流程
- 类风病学 类风病学 类风病学
背景情况:
- 液体喷射器的初级原子化在许多工业应用中至关重要,包括燃料注射系统.
- 了解非牛顿流体特性 (如剪切稀释) 对原子化的影响,对于优化这些过程至关重要.
- 以前的研究经常简化了流体的行为,需要对剪切稀释效应进行详细的调查.
研究的目的:
- 通过使用直接的数值模拟,研究剪切稀释液体喷射在停滞气体中的初级原子化.
- 与牛顿流体相比,分析不同剪切稀释模型 (动力定律和卡罗-亚苏达) 对滴滴特性的影响.
- 在原子化过程中量化滴水体积,形状和其他属性的变化.
主要方法:
- 使用直接数值模拟 (DNS) 来建模原子化过程.
- 牛顿流体特性 (类似柴油) 被用作基线,并研究了两个剪切稀释模型 (动力定律,卡罗-亚苏达).
- 一个新的跟踪算法识别并记录了随着时间的推移滴滴的特征 (体积,表面积,质量中心).
主要成果:
- 发现液气接口的剪切稀释行为会影响滴滴体积和形状.
- 尽管测试模型之间的平均粘度有显著差异,但核心喷气的第一和第二阶段速度和体积分数统计数据基本保持不变.
- 使用概率密度函数来比较不同类型的风湿学模型中的滴滴特征.
结论:
- 液体的质性质,特别是剪切薄化,在液体喷气的初级原子化中起着重要作用.
- 虽然接口现象对剪切稀释敏感,但喷气核的散流特征受到影响较小.
- 这些发现有助于更准确地建模燃料注入和其他涉及非牛顿流体的原子化过程.
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