裂缝性碳酸盐岩油藏酸压井产量递减规律研究

Study on Production Decline of Acid Fractured Well In Carbonate Reservoir

针对裂缝性油藏酸压后形成的垂直裂缝,建立了考虑裂缝表皮的裂缝性油藏有限导流垂直裂缝井数学模型,求得裂缝性油藏有限导流垂直裂缝井无因次产量表达式,并绘制了无因次产量随时间变化的双对数特征曲线图,对其产量递减规律进行了分析。分析结果表明,裂缝表皮和无因次导流能力对垂直裂缝井产能的影响主要集中在生产早中期。其产量递减曲线类似于普通直井,具有相对平缓递减和快速递减两个阶段。裂缝传输系数决定平缓段出现的早晚,储容比决定相对平缓递减阶段维持时间长短。

According to vertical fracture by acid fracturing in fissured reservoir,the mathematical model considered fracture skin for wells with finite conductivity vertical fractures in fissured reservoirs is developed and the formula of dimensionless rate is obtained.Furthermore,typical curves of dimensionless rate to time are drawn.Analysis of the affecting factors to rate decline indicates that the influence of fracture skin and dimensionless fracture conductivity on the production rate of vertical fracture is focus on the early-middle of production stage. Its declined curers of production are similar to ordinary vertical one,having two stages of the relatively gentle and rapid decline.Fracture transmission coefficient determines early or late of the emergence time of relative mild declined stage,while,storage ratio determines the time duration.