考虑射孔的井底压力计算

Calculation of Bottom Hole Pressure Considering Perforation.

将射孔孔眼考虑成线源 ,采用无限大平面中任意方向线段源的瞬时源函数Gxy及铅直方向的瞬时源函数Gz,根据Newman乘积原理得出一个射孔孔眼的Green函数Gxy·Gz,并根据叠加原理给出实际射孔情况下的地层压力、井底压力表达式。为了验证解的准确性 ,与有限元解进行比较 ,结果表明 ,当时间较小时 ,两种方法所计算的结果略有差别 ;当时间较大时 。

Considering the perforation tunnel as a line source and utilizing, on an infinite plane, the instantaneous source function G xy of line source at any direction and the instantaneous source function G z at vertical direction, Green function G xy ·G z of perforation tunnel is obtained in accordance with Newman product prin~ ciple, and the expression for formation pressure, bottom hole pressure under the condition of actual perforation is given in accordance with superposition principle. For verifying accuracy of the solution, it is compared with finite element solution, the result indicates that, when time value is small, the calculation results of two methods have slight difference; when time value is big, the calculation results of two methods are identical. Subject heading