Research on Water Cone Behavior in a Heavy Oil Reservoir with Bottom Water Considering the Starting Pressure Gradient

[Image: see text] Aiming at the unclear reorganization of the water cone shape and its flooding scope for a horizontal well in a heavy oil reservoir with bottom water, a new method was proposed in this paper to establish a numerical model with the starting pressure gradient (SPG) by commercial software to study water cone behavior. The results show that there exists SPG in heavy oil reservoirs ranging from 10(–4) to 10(–3) magnitude with mobility under 30 μm(2)/mPa·s. With a mobility of 33 μm(2)/mPa·s, the water cone and flooding scope from the model with SPG is 120 m shorter than that without SPG. Upon increasing the mobility from 11 to 90 μm(2)/mPa·s, the flooding scope of the model with SPG changes from 125 to 315 m, showing a power exponential form. The new method proposed in this paper was significant for the water cone behavior study and has broad applications in heavy oil reservoir development in the future.