钻井液与完井液2024，Vol.41Issue(3)：288-295,8.DOI:10.12358/j.issn.1001-5620.2024.03.002
高温深井温压耦合下流体性质对井筒压力的影响特性
Study on Effects of Fluid Properties on Borehole Pressure under Temperature and Pressure Coupling in High Temperature Deep Wells
摘要
Abstract
High temperature high pressure(HTHP)environment in deep wells plays an important role in mud rheology control;omitting its effects will lead to an inaccurate knowledge of hole pressures and a negative influence on safe drilling.Based on the principle of energy conservation,a borehole temperature computation model is established.In this model a method of computing borehole temperature by coupling the effects of temperature and pressure is built up taking into account the effects of the fluid flow state on temperature and pressure.The reliability of the model is verified using data acquired from field operations.The study results show that the effect of temperature on the density and rheology of a drilling fluid is more important than the effect of pressure.As a well becomes deeper,the density and yield point of the drilling fluid in the annulus are also increasing.As the circulation time increases,the bottom hole temperature is decreasing,the density,yield point and flow index of the drilling fluid in the annulus are increasing,while the thickening index is decreasing.The ECD of the drilling fluid in the annulus under coupled temperature and pressure condition is lower than the ECD of the fluid in the same annulus without considering the coupling of temperature and pressure,the difference between the two ECD is 0.067 g/cm3.Hence,if the effects of temperature and pressure coupling on the density and rheology of a drilling fluid are not considered,a mud density lower than that is necessary to balance the formation pressure will be designed,and well kick and blowout may be induced.The results and understanding of this study provide a key theoretical base for precise evaluation of temperature and pressure in an ultra-deep well.关键词
高温高压/温压耦合/流体密度/流变参数/压力分布Key words
High temperature high pressure/Coupling of temperature high pressure/Fluid density/Rheological parameter/Pressure distribution分类
能源科技引用本文复制引用
刘平江,和建勇,张晔,毕毅,张瑞华,杨谋..高温深井温压耦合下流体性质对井筒压力的影响特性[J].钻井液与完井液,2024,41(3):288-295,8.基金项目
国家自然科学基金项目"干热岩型地热泡沫钻井流体相变行为下井筒温度压力响应特性研究"(52174008). （52174008）
