自振脉冲气液射流振荡及其冲蚀煤岩效应

发布时间：2018-03-03 06:53

  本文选题：自振脉冲气液射流　切入点：煤岩　出处：《中国矿业大学学报》2015年06期 　论文类型：期刊论文

【摘要】：为提高射流利用率,提出一种基于自吸渗气方法的自振脉冲气液射流,基于水声学与流体动力学理论建立其频率模型,并通过考察射流冲击作用下等强度悬臂梁振动的加速度变化规律分析射流频率特性,继而以煤岩体为试件检验射流冲蚀效果.结果表明,自振脉冲气液射流的振荡频率随含气率α上升在初始段急剧衰减,在α=0.5达到极小值;射靶实验表明脉冲气液射流振荡频率随腔长L增加呈递减趋势,而加速度随无量纲腔长变化在L/d1(d1上喷嘴直径)≈2.2出现一极大值,且极值点位置较自振脉冲水射流(L/d1≈2.5)左移;煤岩冲蚀实验显示脉冲气液射流最大冲蚀体积较自振脉冲水射流提高约44%,且两者极值处对应的腔长与射靶实验结果极为接近.
[Abstract]:In order to improve the efficiency of jet utilization, a self-oscillating pulse gas-liquid jet based on self-suction gas was proposed, and its frequency model was established based on the theory of hydroacoustics and hydrodynamics. The frequency characteristics of the jet are analyzed by investigating the acceleration variation of the vibration of the cantilever beam with equal strength under the action of jet impingement, and then the erosion effect of the jet is tested with the coal and rock mass as the specimen. The results show that, The oscillation frequency of the self-oscillating pulse gas-liquid jet decreases sharply with the increase of the gas holdup 伪 in the initial stage, and reaches the minimum value at 伪 ~ (0.5), and the target shooting experiment shows that the oscillation frequency of the pulsed gas-liquid jet decreases with the increase of the cavity length L. However, the acceleration varies with the length of the dimensionless cavity at the nozzle diameter of L / D _ 1 / d _ 1) = 2.2, and the position of the maximum point is shifted to the left than that of the self-oscillating pulsed water jet (L / D _ 1 鈮，

本文编号：1559966