高温高压气井全井筒温度-压力耦合模型研究  

On the coupled model of temperature-pressure in the whole wellbore of HTHP gas wells

作　　者：韩鑫 HAN Xin(CNOOC(China)Co.,Ltd.Hainan Branch,Haikou,Hainan 524057,China)

机构地区：[1]中海石油(中国)有限公司海南分公司,海南海口524057

出　　处：《世界石油工业》2023年第4期86-92,共7页World Petroleum Industry

摘　　要：海上气井受井型和储层温压的影响,压力计往往未能下到储层中部深度,导致产能测试曲线异常,试井解释特征曲线井储段过长,甚至掩盖部分径向流反映。为提高试井分析数据精度,需优选井底压力计算方法。针对南海该类气井的特点,从井口分段建立大气、海水及储层的外部温度场以获得压力计算的全井筒温度场变化和对应的传热模型。井底压力计算考虑了测试阶段相态变化的影响,优选温度‒压力耦合的求解方法,通过迭代计算首次得到开井生产和关井压力恢复全过程井底压力数据,与实测压力对比误差在3‰以内,有效解决了高温高压气井产能测试曲线异常的问题,井底恢复压力计算值达到试井解释的精度要求。该方法在莺歌海区域得到了有效得验证及应用,为推广应用到高温高压气井或水下井口的气藏提供了指导意义。Influenced by the well type and the temperature and pressure of eservior,the pressure gauge fails to descend to the middle depth of the reservoir,which leads to the frequent abnormality of the productivity test curve.The interpretation of the well storage being too long,and even covers up part of the radial flow reflection.The key to solving this problem is to find a method for calculating the bottom hole pressure whose accuracy meets the requirements of the well test analysis data.Ac-cording to the characteristics of such gas wells in the South China Sea,the external temperature fields of atmosphere,seawater and reservoir are established from the wellhead section by section to obtain the whole wellbore temperature field change of pressure calculation and the corresponding heat transfer model.The solution method of temperature pressure coupling is op-timized for bottom hole pressure calculation,and the calculation of bottom hole pressure takes into account the influence of phase change.Through iterative calculation,the bottom hole pressure data of HTHP gas wells are obtained.The comparison error with the measured pressure is within 3‰,and effectively solves the problem of abnormal productivity test curve of HTHP gas wells,and the calculated bottom hole recovery pressure meets the accuracy requirements of well test interpretation.This method has been effectively verified and applied in Yinggehai area,providing guidance for popularization and application to underwater wellhead gas reservoirs.

关 键 词：油气井测试 气井 温度场 传热模型 井底压力 耦合模型 

分 类 号：TE53[石油与天然气工程—油气田开发工程]