应急放喷工况下钻井四通的耐冲蚀性能

Analyses of Anti-erosion Performance of Drilling Cross under Emergent Discharge Conditions

针对大排量应急放喷工况下钻井四通冲蚀问题,运用CFD软件模拟了钻井四通在日放喷量为100~1 000万m^3、日出砂量为7.5~38.5 m^3工况下的冲蚀情况。结果表明:随着日放喷量的增加,四通支管段气体流速增至当地音速,且压降增至0.98 MPa;当日放喷量超过300万m^3,四通内壁主要冲蚀区域由主通上壁面转移至主通与支管连接处和支管末端,最大冲蚀速率增至19.42×10^(-7) kg/(s·m^2);当日放喷量为1 000万m^3、日出砂量由7.7m^3增大至38.5m^3时,最大冲蚀速率由3.68×10^(-7) kg/(s·m^2)增至19.42×10^(-7) kg/(s·m^2),模拟结果与现场实测数据基本吻合。

Aiming at the problem of erosion of drilling cross in large displacement and emergent discharge condition,CFD software was used to simulate the erosion of the drilling cross in working conditions of daily discharge capacity of 1-10 million m^3 and sunrise sand volume of 7.5-38.5 m^3.The results show that with the increase of daily discharge volume,the gas flow rate of branch pipe section of the drilling cross increased to the local sound velocity,and the pressure drop increased to 0.98 MPa.When the discharge volume was more than 3 million m^3,the main erosion regions of the inner wall of the drilling cross were transferred from the upper wall of main passage to the joint of main passage and branch pipe and the end of the branch pipe,and the maximum erosion rate increased to 19.42×10^-7kg/（s· m^2）. When the discharge volume was more than 10 million m^3 and the sand volume increased from7.7 m^3 to 38.5 m^3,the maximum erosion rate increased from 3.68×10^-7kg/（s·m^2）to 19.42×10^-7kg/（s·m^2）.The simulation results are basically consistent with measured field data.