Analysis of the Flow Pattern in the Foam Drilling Wellbore under Typical Eccentricity
Borehole eccentricity often happens in drilling process with the extensive application of foam drilling.For foam drilling,wellbore annulus complex flow pattern caused by the borehole eccentricity and the complexity of the flow rules of the non-Newtonian fluid.According to the statistics of the typical well structures in northeastern Sichuan fields,the flow model of the drilling fluid in a third section 8-1/2"annulus with typical borehole eccentricity was established.The flow pattern under various models was studied by using fluid numerical analysis method.The analysis reveals that in the foam drilling process,the erosion degree of the drill string is greater than that of the wellbore wall and that the presence of annulus eccentricity increases the peripheral velocity of the annulus fluid and reduces the axial velocity thus reduces the carrying capacity of the annulus fluid.The analysis also indicates that the impact of the drill string rotational speed on the eccentric annulus flow field is much larger than that on the concentric annulus.As the rotational speed increases,annular velocity increases,but the speed has little effect on the annulus and wellbore stability.
foam drilling power-law fluid annulus velocity eccentricity ratio numerical simulation
Fucheng Deng Xianzhong Yi Lihua Wang Xuefeng Shen Qimin Liang Ning Gong
Yangtze University,Jingzhou,Hubei,434023 China Petroleum Technology&Development Corporation,Beijing,100009 Research Institute of Petroleum Exploration&Development,Beijing,100083 Tianjin Branch of China National Offshore Oil Corporation Limited,Tianjin,300450
国内会议
武汉
英文
324-329
2019-11-01（万方平台首次上网日期，不代表论文的发表时间）