基于流-固耦合的煤层脉冲注水数值模拟研究  

Study on numerical simulation of pulse water injection in coal seam based on flow-solid coupling

作　　者：祁云霞 连清旺[1,2] QI Yunxia;LIAN Qingwang(School of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Key Laboratory of In-Situ Modified Mining of Ministry of Education,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学矿业工程学院,山西太原030024 [2]太原理工大学原位改性采矿教育部重点实验室,山西太原030024

出　　处：《矿业安全与环保》2024年第5期29-37,45,共10页Mining Safety & Environmental Protection

基　　金：山西省自然科学基金项目(201901D111071)。

摘　　要：为了研究煤层脉冲注水技术的增湿机理及脉冲参数对煤体力学特征和煤体湿润效果的影响规律,基于流-固耦合理论建立脉冲注水几何模型,采用Rfpa软件和Comsol Multiphysics 5.4软件内置脉冲压力函数进行数值模拟。模拟结果显示,相较于定压注水,脉冲交变压力注水对煤层的“水楔劈裂”作用明显增强;随着脉冲时间的增加,煤体孔隙压力呈现出周期性波动上升的趋势;孔隙压力增加,煤体有效应力相应降低;脉冲压力和时间与煤体湿润半径之间存在一定的数学关系,而脉冲角频率对湿润效果的影响甚微。在进行脉冲注水时可采用高压低频脉冲的注水方式并保证一定的注水时间,能起到较好的煤体增湿效果。In order to study the humidification mechanism of coal seam pulse water injection technology and the influence law of pulse parameters on the mechanical characteristics of coal and the wetting effect of coal,the geometric model of pulse water injection was established based on fluid-solid coupling theory,and the pulse pressure function built in Rfpa software and Comsol Multiphysics 5.4 software were used for numerical simulation.The simulation results show that compared with the constant pressure,the effect of pulse alternating pressure on the“water wedge splitting”of coal seam is significantly enhanced.With the increase of pulse time,the pore pressure of coal shows a tendency of periodic fluctuation and rise.With the increase of pore pressure,the effective stress of coal decreases accordingly.There is a certain mathematical relationship between the pulse pressure and time and the wetting radius of coal,but the pulse angular frequency has little effect on the wetting effect.In pulse water injection,high pressure and low frequency pulse water injection method can be adopted and a certain injection time can be guaranteed,which can play a better humidification effect of coal.

关 键 词：流-固耦合 脉冲注水 数值模拟 孔隙压力 湿润半径 

分 类 号：TD714[矿业工程—矿井通风与安全]