基于超音速喷嘴的超细干粉喷射行为的数值和实验研究
Hongen Ge1, Xin Zhang1, Yuqi Liu1
1College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao 266590, China.
ACS omega
|November 25, 2024
概括
优化干粉灭火包括了解超细颗粒如何在高速空气喷射中表现. 喷嘴压力和颗粒大小等关键因素影响喷射性能和颗粒分布,以更好地灭火.
科学领域:
- 流体动力学 流体动力学
- 灭火技术 灭火技术
- 颗粒物运输 颗粒物运输
背景情况:
- 提高干粉喷射灭火的效率对于有效的火灾控制至关重要.
- 了解高速气体流中的超细颗粒的行为对于优化输送至关重要.
研究的目的:
- 为了研究超细干粉颗粒在高马赫数压缩空气喷流中的速度变化和空间分布.
- 分析喷嘴压力比率,粒子直径和质量流速对喷气体特性的影响.
- 为设计改进的灭火喷嘴结构提供见解.
主要方法:
- 使用SST k-ω流模型和气体固体双相合模型进行模拟.
- 进行了超细干粉喷射实验,以验证模拟结果.
- 分析的参数包括马赫数和辐射扩散宽度.
主要成果:
- 发现粒子大小的增加削弱了粒子流动性.
- 萨夫曼提升力显著影响粒子分布,在中心轴附近创建一个没有粒子的区域,喷嘴膨胀角度大.
- 较高的喷嘴压力比率和较低的干粉质量流速提高了核心喷气区域的粒子速度.
结论:
- 颗粒的特性和喷嘴设计参数极大地影响干粉喷射性能.
- 这些发现为灭火喷嘴的结构设计提供了有价值的指导,以提高效率.
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