Effect of drainage height and permeability on SAGD performance

Steam assisted gravity drainage (SAGD) is now considered a commercially successful technique for the recovery of heavy oil and bitumen in Canada. However, our theoretical understanding of the process is based on greatly simplified analytical models which do not always provide accurate assessment of the influence of various process variables. Hence there remains a need for improved analytical models. This paper presents a new semi-analytical model to predict the oil production rate in SAGD. This model was used to study the effects of drainage height and reservoir permeability on production performance.In this model heat conduction problem ahead of the interface is solved by heat integration method (HIM) in an arbitrary orthogonal coordinate system under unsteady-state condition. Several dimensionless numbers are introduced and their relationships are investigated for better understanding of the combination of heat conduction and gravity drainage mechanisms.