在同轴原子化中,对剪切薄化凝喷气的线性不稳定性分析,具有屈服应力
Yufan Wang1, Pingping Chai2, Feng Yao3
1National Energy Coal Gasification Technology Research and Development Center, Shanghai Engineering Research Center of Coal Gasification, Engineering Research Center of Resource Utilization of Carbon-containing Waste with Carbon Neutrality, Ministry of Education, East China University of Science and Technology, Shanghai 200237, China. zhaohui@ecust.edu.cn.
Soft matter
|July 20, 2023
概括
这项研究揭示了喷嘴设计和流体特性如何影响凝喷气原子化. 螺纹喷嘴和更高的产量应力提高了喷雾性能和稳定性.
科学领域:
- 流体动力学 流体动力学
- 类风病学 类风病学 类风病学
- 空气动力学 在空气动力学.
背景情况:
- 同轴气爆原子化对于各种工业过程至关重要.
- 了解像凝喷流这样的非牛顿流体的行为是复杂的.
- 喷嘴几何形状和流体产量应力对原子化的影响需要详细调查.
研究的目的:
- 在实验和理论上研究螺纹喷嘴的作用,并在凝喷气机的同轴气爆原子化过程中产生应力.
- 为了确定不同喷气式分离类型的过渡条件.
- 分析喷嘴线程和产应力对喷雾角度和喷射稳定的影响.
主要方法:
- 风病学测试以描述凝喷气的特性.
- 高速流动可视化技术,观察喷气破裂动态.
- 线性稳定性分析,以理论地研究产量应力和喷嘴设计的影响.
主要成果:
- 识别了不同的破裂模式 (振荡,膜,纤维,超脉冲) 凝喷气机随着空气流速的增加.
- 在Weissenberg-Ohnesorge (We-Oh) 数值图上绘制的确定过渡条件.
- 观察到一个螺纹喷嘴会扩大喷射喷射角度,最大喷射角度在We = 600.
- 线性稳定性分析表明,增加的产量压力降低了占主导地位的不稳定增长率,而螺纹喷嘴则增加了它.
结论:
- 喷嘴设计,特别是气侧线程,显著影响喷雾角度.
- 收益应力在稳定凝喷气中起着至关重要的作用,影响断裂动态.
- 该研究提供了对凝喷气原子化的全面了解,这对于优化工业喷雾应用至关重要.
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