A new method to calculate sweep efficiency of horizontal wells in heterogeneous reservoir

Abstract

This paper discusses the development challenges of an offshore fluvial oil reservoir with horizontal wells. In highly productive sandstone reservoirs, horizontal wells suffer from uneven flow profile and subsequent premature coning effects because of sand heterogeneity and heel to toe effect. Moreover, excessively increasing the production rate or horizontal well length can increase the risk of limited sweep efficiency, resulting in remaining oil in the toe or poor sand with low permeability. First, we analyze the characters of fluvial oil reservoir focusing on sand architecture and heterogeneity. Second, the sweep efficiency was calculated by the production data. Finally, we optimize inflow control device (ICD) for several wells and compare the response of ICD wells with conventional screen completion wells.

A novel model for predicting the productivity index of horizontal/vertical wells based on Darcy's law, drainage radius, and flow convergence

“…Many scholars have studied the PI of horizontal wells [ 5 , 6 , 14 ] and vertical wells [ 1 , 2 , 12 ] over the years. The main components adopted in the studies are Darcy's equation, reservoir geometry, and the flow regime, which varies for vertical or horizontal wells.…”