三孔双渗气藏气井产量的变化特征及应用

CHARACTERISTIC ANALYSIS OF GAS WELL DELIVERABILITY VARIATION IN TRIPLE-MEDIUM RESERVOIRS

碳酸盐岩储层的储集空间复杂,主要有孔隙、洞穴和裂缝三大类,该类气藏具有不同于均质和双重介质气藏的特殊产能变化规律,过去对其中起主导作用的影响因素定量化了解不够。通过建立和求解洞穴-裂缝-孔隙三重介质气藏定井底流压生产数学模型,绘制了无阻流量变化图版,根据该图版可以分析产量随时间的变化特征,分析了裂缝和溶洞储容比、基质和溶洞窜流系数对气井产能变化特征的影响,为正确认识三重介质气藏气井产量变化规律提供了理论依据。

The reservoir space is various and complicated in carbonate gas reservoirs,including pores,fractures and cavitys. There exists much different deliverability changing rules from homo-geneous or fractured and porous gas reservoirs. In the past,the main influencing factors might not be recognized sufficiently and quantita-tively. Through establishing a mathematical solution model for the constant bottomhole flowing pressure in the triple-medium reser-voirs,the plate of open-flow capacity was drawn. Based on the plate,the productivity characteristic and sensitive factors were ana-lyzed as time variation. The model provided a theoretical basis for recognizing the gas well productivity variation in triple-medium gasreservoirs.