摘要
A computational fluid dynamics(CFD)numerical simulation and field experiment were used to investigate optimal operating parameters of high-pressure jet grouting equipment and clarify the boundary law of the injection area in the remediation process.The response surface optimization design results show that the optimal injection pressure is 30 MPa,rotation speed is 23 r/min,commission speed is 30 cm/min,and the optimal injection diameter is 147.3 cm.Based on the CFD numerical simulation,the ratio of the injection core,turbulent zone,and seepage zone is approximately 1∶4∶2.The distribution law of jet core,turbulence zone and seepage zone at different cross-sections under 30 MPa operating conditions is as follows:The jet core radius is approximately 100 mm,the turbulence zone is mainly distributed at 100 to 500 mm,the seepage zone is mainly distributed at 500 to 700 mm,the seepage zone could be completed within 2 h,and the proportion of the three boundary zones in the injection zone is similar to that of the numerical simulation.This study provides theoretical parameters and practical reference for the remediation of deep pollution via in-situ chemical oxidation in the Loess Plateau soil environment.
采用CFD数值模拟和现场实验方法,考察高压旋喷设备最佳运行工况参数,探讨修复过程中注射区域分界规律.通过响应面优化设计得出高压旋喷运行最佳注射压力为30MPa,旋转速度为23r/min,提升速度为30cm/min,最佳注射直径为147.3cm.通过CFD数值模拟出注射区域分界的喷射核、湍流区和渗流区比例约为1∶4∶2.在30MPa运行工况下不同断面喷射核、湍流区和渗流区的分布规律为:喷射核半径在100 mm左右,湍流区主要分布在100~500mm处,渗流区主要分布在500~700mm,且渗流区域可在2h内完成.通过现场实验得到的注射区域3个分界区比例与数值模拟结果类似.该研究为黄土高原土壤环境下原位化学氧化修复深层污染提供了理论参数和实践参考.
基金
The National Natural Science Foundation of China(No.41967043,52160003)
the Natural Science Foundation of Gansu Province(No.20JR5RA461)
the Key Project of China Railway Southwest Research Institute Co.,Ltd.(No.2018-KJ003-Z003-XB)
the Industrial Support Program of the Higher Education of Gansu Province(No.2020C-40).
