Numerical Simulation on Well Pattern Adjustment Involving Starting Pressure Gradient for Low Permeability Oilfield

• Main Authors: Yin Daiyin, Song Xin, Zhang Xiaoran, Zhang Chengli
• Format: Article
• Language: English
• Published: IFSA Publishing, S.L. 2013-10-01
• Series: Sensors & Transducers
• Subjects: Low permeability; Mathematical model; Well pattern adjustment; Starting pressure gradient; Numerical simulation.
• Online Access: http://www.sensorsportal.com/HTML/DIGEST/october_2013/P_1421.pdf

The development of low permeability oilfield has certain particularities and difficulties. According to the characteristics of the low permeability oilfield, based on the non-Darcy seepage mechanical mechanism of low permeability core, and considering the starting pressure gradient, the three-dimensional three-phase non-Darcy seepage mathematical model of low permeability oilfield was set up and the results were obtained by difference method. Taking the block 55 of Chao Yang Gou oilfield for example, the well pattern adaptabilities of the four well pattern, rhombic inverted nine-spot well pattern, inverted nine-spot well pattern, rectangular five-spot well pattern and unequal spacing linear well pattern were studied by the numerical simulation method. The results showed that the rhombic inverted nine-spot well pattern was adopted in the early development period of the low permeability oilfield, and then turned into the rectangular five-spot well pattern or the unequal spacing linear well pattern through injection-production adjustment. The corresponding ultimate recovery factors were improved with 1.12 and 1.36 percentage points, respectively. The reasonable well-pattern adjustment method could be selected according to the actual situation of the oilfield.