A prediction model used for the heating boundary of steam chamber in the startup stage of SAGD horizontal well

Steam assisted gravity drainage (SAGD) technology is divided into stages, i.e., startup stage and production stage. The quantitative calculation of steam chamber development boundary in the horizontal section in the SAGD startup stage is the important basis for discriminating the optimal beginning time of production stage. In this paper, the model used for calculating the heating radius of each temperature measurement point in the horizontal section was established by introducing the downhole temperature attenuation testing method on the basis of the SAGD startup process analysis and the heat conduction equation of steam heating reservoir. This model can be used to calculate the steam heating boundary along the horizontal section and discriminate the development morphology of steam chamber. Then, the bottom-hole temperature measurement data of a certain SAGD horizontal well in Xinjiang Oil field was collected for study. The calculation results by this model were compared with the measured data. It is indicated that the quantitative calculation result by this model is in accordance with the qualitative discrimination result based on the measured data. The research results provide a new method for discriminating the conversion timing of SAGD production stage and monitoring the development homogeneity of steam chambers.