摘要
针对对低流度油藏,对我国东部某油田低流度油藏岩心进行"气泡法"启动压力测试与单相渗流实验.实验结果表明:流度越低,启动压力梯度越高,并且满足相关性非常高的乘幂变化关系.通过对岩心单相渗流实验得到的数据进行分析归纳,得到其流体非线性渗流段启动压力梯度的计算式.对其特征曲线进行渗流特征理论分析,得到最小启动压力梯度与拟启动压力梯度的理论值及启动压力梯度与驱替压力梯度的关系函数.由非线性渗流区长度的数学表达式可知,流度越低,其非线性渗流区越宽.该成果为低流度油藏启动压力梯度的研究提供了相关方法和依据.
The reservoir has problems of high threshold pressure gradient which makes reservoir fluid seepage flow disobey Darcy's law.Bubble method threshold pressure gradient tested and single-phase seepage flow experiments have been done whose cores come from a low mobility reservoir of oilfield,which lies in the eastern of China.The results showed that the seepage flow of low mobility reservoir has threshold pressure gradient and nonlinear seepage flow feature.The lower the mobility is,the higher the threshold pressure gradient is.The threshold pressure gradient has high relativity power correlation with mobility.An equation is also obtained to calculate the threshold pressure gradient in nonlinear seepage flow by analyzing to the data got form the single-phase seepage flow experiments.Analyzing to the nonlinear seepage flow features,minimum threshold pressure gradient and pseudo-threshold pressure gradient were obtained.Function of relation between threshold pressure gradient and displacement pressure gradient was also proposed.Based on mathematic expression for the area of nonlinear seepage flow,the lower mobility is,the wider nonlinear seepage flow area is.Through the research of low mobility reservoir threshold pressure gradient can provide relative basis for its exploitation.
出处
《大庆石油学院学报》
CAS
北大核心
2010年第1期39-42,59,共5页
Journal of Daqing Petroleum Institute
基金
国家自然科学基金项目(50804041)
关键词
低流度油藏
启动压力梯度
气泡法
单相渗流
非线性渗流区
low mobility reservoir
threshold pressure gradient
bubble method
single-phase seepage flow
nonlinear seepage flow area
