建立了任意形状油藏考虑注采比影响的不稳定渗流数学模型,采用有限元方法进行了求解,获得了井底压力。绘制分析了压力恢复试井典型曲线,给出了恢复试井典型曲线拟合分析的实例。研究表明:注采比对井位压力恢复曲线形态具有显著的影响,注采比越大,注入流体对压力恢复过程影响越大,后期压力恢复速度越快,曲线上翘时间越早;油井与边界距离越近,曲线上翘的时间也越早。研究对于正确分析密井网条件下压力恢复试井资料,获得可靠的储层动态参数具有十分重要的意义。
A transient flow mathematic model for reservoirs with arbitrary shapes in consideration of influence of injection-production ratio is developed, and it is solved by using Finite Element Method (FEM) , and bottom hole pressure is obtained. Type curves of build up test are drawn and analyzed, and match analysis examples of type curves of build up test are given. Research indicates that injection-production ratio and well locations have consid-erable influence on shapes of build up curves. The higher the injection-production ratio is, the greater the influence of the injected fluid on build up process is; the faster the build up velocity at the later stage is, the earlier the time for curve to upwarp is; the shorter the distance between oil well and the boundary is, the earlier the time for curve to upwarp is. This study has great significance for correctly analyzing build up data under condition of dense well patterns and obtaining reliable performance parameters from reservoirs.