【24h】

Effect of flow conditions on bum rates of metal particles

机译:流动条件对金属颗粒Bum速率的影响

获取原文

摘要

Micron-sized aluminum and titanium powder particles were carried by an air flow into a focal point of a CO_2 laser beam and ignited. In different experiments, the ignited particles continued to bum in laminar or turbulent flow conditions. A computational fluid dynamic model was used to describe characteristics of the turbulent flow. Particle burn times and temperatures were measured optically. Effect of turbulent flow conditions was observed on combustion characteristics for both aluminum and titanium powders. For both powders, luminous combustion streaks became shorter. For aluminum, the brightness of the streak and the optically measured temperature were also substantially reduced in the turbulent flow conditions. For titanium, reduction in both streak brightness and temperature were minor for different flow conditions. Compared to the laminar flows, the burn rates of aluminum and titanium were observed to increase more than 4 and 2 times, respectively, in the turbulent flows. Simple empirical correlations are proposed for both metals enabling one to predict the increase in the metal particle mass burn rate for turbulent flow conditions taking into account the particle size and such flow characteristics as Kolmogorov length scale and average kinetic energy.
机译:微米尺寸的铝和钛粉末颗粒通过的空气流带入CO_2激光束和点燃的焦点。在不同的实验中,点燃颗粒继续层流或湍流流动条件下燃烧。的计算流体动力学模型用于描述紊流的特性。颗粒燃烧时间和温度是光学测量的。没有观察到对两种铝和钛的粉末燃烧特性的湍流条件的影响。对于这两种粉末,发光燃烧条纹变短。对于铝,条纹和光学测量的温度的亮度也基本在湍流条件降低。对于钛,减少在两个条纹亮度和温度是小调不同流动条件。相较于层流,观察到的铝和钛的燃烧率,以增加超过4倍和2倍,分别在湍流流动。简单的经验相关性提出了两种金属使一个预测在金属粒子的质量燃烧速率考虑到粒径和这样的流动特性的Kolmogorov长度尺度和平均动能湍流条件的增加。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号