地下储气库注采井井底压力计算研究

Bottom hole pressure calculation of injection and production wells of underground gas storage

根据能量守恒原理,利用伯努利方程,推导了地下储气库注气期、关井期井底压力计算方程,用改进的平均温度和平均偏差系数法、迭代法及逐点计算法计算注气阶段井底流压、关井阶段井底静压。依据Hagedorn-Brown两相垂直管流压力梯度方程,用改进的平均温度和平均偏差系数法、龙格库塔数值解法及逐点计算法计算产气阶段井底流压。注采井井底压力计算能为储气库注采周期内盖层和断层处压力变化、库容量、工作气量等研究提供理论基础。

According to the principle of the conservation of energy and Bernoulli＇ s equation, the bottom hole pressure calculation equation of gas injection period and shut in period of underground gas storage were deduced, moreover, the bottom hole flowing pressure in gas injection period and bottom hole static pressure in shut-in period were calculated by the improved average temperature and average deviation coefficient method, iterative method and point by point calculation method. Based on the pressure gradient equation of Hagedorn-Brown two-phase vertical conduit flow, the bottom hole flowing pressure in gas production period was calculated by the improved average temperature and average deviation coefficient method, Runge-Kutta numerical solution method and point by point calculation method. The bottom hole pressure calculation of injection and production well provided theoretical basis for the pressure change, storage capacity and working gas volume of capping formation and faults in injection and production cycle.