摘要
本文通过对弯管内气固两相流动的数值计算,建立了固体颗粒在惯性离心力的作用下,从气流中向弯管外侧壁面分离的规律与斯托克斯准则数和颗粒在弯道内运动角度的关系.对水平肘管内气固两相流动特性进行了实验研究,得出在 R_0/d 分别为2和4、一次风速分别为15m/s 和20m/s、煤粉平均粒径为50～60μm、煤粉浓度为0. 2kg/m^3的工况下,当煤粉-空气混合物流过弯头的角度≥45°时,约有80%以上的煤粉颗粒沿弯管外侧形成一股高煤粉浓度的气流流出.这一结果与数值计算结果较吻合.实验与理论计算结果为开发煤粉浓缩燃烧技术提供了重要的理论依椐.
By means of numerical computation,the relations between the flow pattern of coal particles and the Stokes number and the angle of movement of the coal particles in the lain bend elbow are determined.Based on the experimental research,the conclusion has been reached that about 80% of the total pulverized coal passes along the outside of bend passage when the ratio of the curvature radius of the elbow to the diameter of primary-air pipe is 2 or 4 and the ve-locities of primary-air are 15 and 20 m/s respectively,the average diameter of coal particles is 50～60μm,the concentration of pulverized-coal is 0. 2kg/m^3 and the angle of movement of the coal-air mixture is equal to or greater than 45 degrees.The experimental results are in good agreement with the numerical computations.The experimental and theoretical results provide an important basis for developing the combustion technique of pulverized-coal in high-inten-sity.
出处
《西安交通大学学报》
EI
CAS
CSCD
北大核心
1990年第4期65-73,共9页
Journal of Xi'an Jiaotong University
基金
国家自然科学基金
关键词
弯管
气固两相流动
浓度分析
elbow pipe
gas-solid flow
concentration distribution
