Download PDFOpen PDF in browserGas Invasion of Wellbore Multiphase Flow in Deepwater DownholeEasyChair Preprint 94978 pages•Date: December 20, 2022AbstractIf formation gas penetrates and migrates inside the wellbore during deepwater drilling, a complex gas-liquid-solid multiphase flow will happen. For good management and blowout avoidance, it is crucial to comprehend the wellbore flow dynamics. A multiphase flow model of multicomponent fluid in the wellbore, including the continuity equation, momentum conservation equation, and energy conservation equation, is deduced and developed, taking into account the dynamic mass and heat transfer process in the wellbore caused by alternating ambient temperature field. Additionally, the appropriate beginning and boundary conditions are suggested for various deepwater drilling working situations, and an effective numerical solution technique is constructed using the methods of dynamic mesh generation and discrete partial differential equation solution. The suggested model is utilized to examine the multiphase flow regulations in the wellbore of a deepwater kicking well. The findings demonstrate that while the temperature changes nonlinearly when annular fluid returns from the bottom hole, the pressure often drops linearly. At the formation portion, the temperature first rises and then falls, while at the saltwater part, the temperature first falls and then rises. Additionally, the rise and expansion of gas in the wellbore result in an approximately quadratic polynomial connection in the pit gain; at the bottom hole, there is a pressure decrease and an increase in the rate of gas influx. The standpipe pressure and bottom hole pressure steadily drop during kick development, which might be a key indicator for kick identification. Keyphrases: Drilling, Geology, Wellbore
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