高压脉冲水射流冲击下受载煤岩的损伤破坏特征及影响因素  

Damage and Breakage Characteristics of Loaded Coal Impacted by High-Pressure Pulse Water Jet and Its Influence Factors

作　　者：冯仁俊 朱永建 邓飞[2] 贺敬 FENG Renjun;ZHU Yongjian;DENG Fei;HE Jing(School of Resource&Environment and Safety Engineering,Hunan University of Science and Technology,Xiangtan 411201,Hunan,China;CCTEG Xinjiang Research Institute,Urumqi 830000,Xinjiang,China;Work Safety Key Lab on Prevention and Control of Gas and Roof Disasters for Southern Goal Mines,Hunan University of Science and Technology,Xiangtan 411201,Hunan,China;Xinjiang Jinchuan Group Co.Ltd.,Korla 841011,Xinjiang,China)

机构地区：[1]湖南科技大学资源环境与安全工程学院,湖南湘潭411201 [2]中煤科工集团新疆研究院有限公司,新疆乌鲁木齐830000 [3]湖南科技大学湖南方煤矿瓦斯与顶板灾害预防控制安全生产重点实验室,湖南湘潭411201 [4]新疆金川集团有限责任公司,新疆库尔勒841011

出　　处：《高压物理学报》2025年第3期57-70,共14页Chinese Journal of High Pressure Physics

摘　　要：为揭示高压脉冲水射流喷嘴内外速度的演化规律及高压脉冲水射流冲击下受载煤岩的冲击破坏特征,基于SPH-FEM(smoothed particle hydrodynamics-finite element method)耦合算法,采用具有正弦函数特性的速度挤压管道内柱塞以实现水射流速度的周期性变化,获得了水射流速度在喷嘴内外的演化规律,对比分析了脉冲射流冲击下受载和非受载煤岩破坏特征的时序特性,揭示了平均速度、脉冲幅值及脉冲频率等关键参数对煤岩损伤破坏特征的影响规律。结果表明:水粒子在喷嘴内外的速度演化过程依次经历了管路中的静止阶段和瞬态突增的低速阶段、喷嘴收敛段的加速阶段、出口直线段的微加速阶段、出喷嘴后的正弦脉冲变速阶段4个阶段。无应力和二维应力加载工况下,煤岩的破碎坑分别呈畸形化发展和碗状向U形演变。二维应力加载工况下,煤岩内部裂纹的衍生及传播受到抑制,煤岩破碎效率降低,脉冲射流的破碎效率高于连续射流的破碎效率。随着柱塞平均速度、脉冲幅值的增大,受载煤岩的破碎深度和破碎面积均呈指数增大。随着脉冲频率的增加,受载煤岩的破碎深度和破碎面积均呈先增大后减小的变化趋势。存在破碎煤岩效果最优的脉冲频率。研究成果可为高压脉冲水射流破碎受载煤岩的效率提升和工艺参数优化等提供理论指导。To elucidate the evolution laws of impact velocity of high-pressure pulse water jet and the breakage characteristics of coal under confining condition,a coupled smoothed particle hydrodynamics-finite element(SPH-FEM)algorithm is adopted.A sinusoidal velocity is applied to the plunger inside the pipeline.The evolution laws of water jet velocity inside and outside the nozzle were obtained,and the temporal damage and breakage characteristics of coal under load and unload conditions impacted by pulse water jet were compared and analyzed.The influence of key parameters such as average velocity,pulse amplitude,and pulse frequency on damage and breakage characteristics of coal was revealed.The results show that the velocity evolution of water jet particles inside and outside the nozzle undergoes four stages:a stationary stage and transient acceleration to a low speed in the pipeline,acceleration inside the convergent section of the nozzle,micro-acceleration inside the straight section of the nozzle,and pulse variation speed following a sinusoidal variation after exiting the nozzle.Under the stress free and two-dimensional stress load conditions,the broken pits of coal specimen exhibit an abnormal development,and undergoes from bowl shape to U-shape,respectively.Two-dimensional stress load has a suppressive effect on the derivation and propagation of internal cracks in coal,reducing the rock-breaking efficiency.Besides,pulse water jet has a higher rock-breaking efficiency on loaded coal specimens than that of continuous water jet.The depth and area of coal fragmentation increase exponentially with the increase of plunger’s average velocity or pulse amplitude,and show a trend of initial increase and subsequent decrease with the increase of pulse frequency,indicating the existence of an optimal pulse frequency for coal fragmentation.The research findings could provide a theoretical guidance for improving the rock-breaking efficiency of high-pressure pulse water jet under confining conditions and optimizing the working pa

关 键 词：脉冲水射流 煤岩破碎 围压 损伤 破坏 影响因素 

分 类 号：O521.9[理学—高压高温物理] TD823[理学—物理]