摘要
采用单水平生产井与多直井复合型井组蒸汽辅助重力泄油开发的稠油渗流规律与传统井型开发的渗流规律不同,水平生产井使原来直井间的注采关系由平行层面转换为立体区域。立体开发三维渗流数学模型的研究以势原理为基础,将水平生产井渗流过程视为三维线汇,建立以水平生产井水平射孔段两端为焦点的椭球形等势面方程;将直井视为多个纵向叠加的平面点源,建立以直井为中心线的圆柱形等势面方程;利用势叠加原理将二者耦合,推导得到复合型井组驱替过程中的渗流压力场和压力梯度场的数学模型。分析了立体开发的动用范围和重力发生泄流时的作用界限,揭示了重力对蒸汽辅助重力泄油开发效果的影响以及重力对油层内压力场和压力梯度场的作用效果,明确了重力会增大压力梯度场在油层内的作用范围和数值大小,特别是在远井地带或由源汇产生的压力梯度较小的地方,重力与驱替压力耦合后的压力梯度促使油层中被加热的流体向水平生产井发生泄流。
There is a big difference in seepage law between the traditional well group and combined well group of single horizontal well and multi vertical wells for SAGD heavy oil recovery. The horizontal well can convert the injection-producer relation between the original vertical wells from a parallel plane one to a three-dimensional region one. Research on three-dimensional seepage mathematical model is based on potential theory. The seepage process of horizontal well was regarded asthree-dimensional line sink and the ellipse potentiometric surface with the focus of the two ends of the perforation intervalin the horizontal well was derived;the vertical wells were regarded as multiple planar point sources through longitudinal stacking and the cylindrical potentiometric surface with vertical well as the center line was derived;the mathematical mod?el of the seepage pressure field and the pressure gradient field during the process of displacement in the composite wellgroup was derived based on the coupling of the above results using potential superposition principle. Producing range ofthree-dimensional reservoir and the effect boundary of gravity discharge were determined. Effect of gravity on SAGD development effect,pressure field and pressure gradient field was analyzed. The results show that the gravity may enlarge pres?sure gradient field at far-wellbore zone or area with low pressure gradient produced by source and sink,which promotes the heated fluid in the oil reservoir to discharge to the horizontal wells.
作者
孙启冀
吕延防
李琳琳
张艺晓
Sun Qiji;Lü Yanfang;Li Linlin;Zhang Yixiao(School of Petroleum Engineering,Northeast Petroleum University,Daqing City,Heilongjiang Province,163318,China)
出处
《油气地质与采收率》
CAS
CSCD
北大核心
2017年第3期71-77,共7页
Petroleum Geology and Recovery Efficiency
基金
黑龙江省创新训练项目"热力-立体开发致密油基质逾渗演化行为描述实验研究"(201610220047)
东北石油大学青年基金项目"直井辅助SAGD开发热-驱-泄耦合渗流规律与数值模拟研究"(NEPUBS201504)
东北石油大学优秀科研人才培育基金"黑龙江省创新后备人才"(SCXHB201602)
