Analytical Models for Conductive Heat Transfer in Gravity Drainage Systems: Steady-State vs. Unsteady-State

Mohsen Keshavarz



This presentation gives the heat transfer mode in SAGD and Steady-state vs. unsteady-state. Since the only model in the literature based on unsteady-state heat transfer mode: Butler’s 1985 requires iterative solution procedure. In that model, steam chamber contacts with OB from the beginning (does not capture the physics of ramp-up). Its results dependent on interface element size. The new model in this work is based on unsteady-state heat transfer theory. It  improved estimations of oil rate and SOR, captures the entire life of a SAGD project, and does not require an iterative solution procedure.  All models have to compromise on some physics. What is important is to recognize those compromises and avoid forcing the model to capture what it is not intended for.