Productivity, water breakthrough and ultimate recovery in horizontal wells with a range of completion types

The effect of completion ID in four different sand control completions was studied using inflow modeling and reservoir simulation. An expandable sand screen and three different IDs of external gravel packs were studied, in various lengths of horizontal well and over a range of flow rates. The ID of a completion affects the performance of a completion through the flow friction pressure generated. The friction pressure is a function of the ID to the inverse 5^th power so even small changes in ID can have an effect. Each completion configuration was assumed to have the same realistic production rate. The friction pressure tends to act as a choke on production from the toe of the well; this concentrates production towards the heel. The expandable sand screen has the lowest inflow at the heel and the smallest ID gravel pack has the highest inflow. The high inflow at the heel draws water up from the underlying aquifer and initiates water breakthrough. The time to breakthrough was calculated using a simple analytical theory. The predicted time agreed well with available production data. A reservoir model was built to further study the heterogeneous inflow. This showed that the larger ID completions gave the best sweep of the reservoir with the highest recovery. The reservoir model was run for a variety of well lengths and productions rates and showed that for long high rate wells the completion with the largest ID gave the best sweep and the longest water breakthrough time.