关键词: 气侵, 水击压力, 井喷喷流, 气液两相, 流型

Abstract: Gas cut during drilling leads to blowout, and fluid flow in the wellbore involves very complex flow phenomena. This paper analyzes the distribution characteristics of the wellbore gas-liquid two-phase flow and the wellbore pressure characteristics during the blowout. The analysis found that the gas expansion rate increases with the decrease of well depth. The volume expansion is the most severe in the well section within about 10% of the wellhead position. When the blowout jet is a gas-liquid two-phase, the type is related to the flow rate of the wellbore mixture and the gas-liquid mass ratio, and the distribution along the entire wellbore is constantly changing.

Key words: gas cut, water hammer pressure, blowout jet, gas-liquid two-phase flow, flow pattern