应力敏感气藏产能方程研究

DILIVERABILITY EQUATION FOR STRESS-SENSITIVE GAS RESERVOIR

针对应力敏感气藏开发存在变渗透率的问题,定义了新的考虑应力敏感的拟压力,并从气体多孔介质渗流力学理论出发,建立了考虑应力敏感影响的气藏二项式产能方程,讨论了该方程参数的计算方法,最后进行了实例分析,讨论了储层应力敏感性对应力敏感气藏产能评价的影响。研究表明:考虑气藏渗透率应力敏感性时预测的气井绝对无阻流量值比渗透率为常数时预测的结果低,预测偏差幅度与储层应力敏感性大小相关,该研究对深入了解应力敏感气藏的产能评价及其开发动态预测有一定的实际意义。

Aiming at the problem of permeability change in exploiting stress-sensitive gas reservoir,the new pseudopressure considering stress sensitivity is defined when the deliverability is analyzed,binomial deliverability equation considering stress-sensitive gas reservoir is set up based on the theory of gas flow through porous media mechanics,and the computation of the equation parameters discussed,at last,casse study is carried out,the influence of reservoir stress sensitivity on stress-sensitive gas reservoir deliverability evaluation is discussed.Research indicates that the value of the forecasted gas well open flow potential considering gas reservoir permeability stress sensitivity is lower than the forecasted one when permeability is constent,the error from forecasting is related to the degree of reservoir stress sensitivity,the research is practically meaningful to understand deliverability evaluation of stress-sensitive gas reservoir and development dynamic forecasting.