Experience shows that high-performance fractures (HPFs) may retain near unit flow efficiency (equivalent to zero skin in a vertical well) and rarely fail, even in highly deviated wells. This may be partly because overly simplistic models of the well flow behavior lead operators to maintain wells at lower production rates than could have been achieved for the same amount of injected proppant with a vertical well completion design. Rigorous models that account for widely accepted rock mechanics fundamentals indicate that the fracture to well connection is compromised in deviated wells and lead to questions whether the bulk of the flow to the well actually passes through the fracture.

Distributed volumetric sources are used in this model to rigorously model a wide variety of possible fracture geometries such as an expanded wellbore due to halo effect, flow strictly through the fracture, and combined flow to a single fracture and to remaining flowing perforations not connected to the fracture. The model also includes turbulent flow effects that may occur for radial flow conditions in the fracture plane or in the reservoir opposite wellbore sections not connected to the fracture as well as high velocity flow through the perforation tunnels. It also computes the effective flow area at the resulting face between the reservoir and the completion to check whether flow velocity exceeds conditions that would risk production of reservoir fines, and estimates the screen flow velocity based on the number of flowing perforations.

This comprehensive view of the HPF completion enables a thorough analysis of the risks of flowing the well at high rate. Field examples show that the new model better depicts the real field conditions in calculating the total skin, flow fractions and the flux for HPF completions in high rate gas and oil wells.

Complete inflow performance behavior for all likely flow patterns for HPF wells in oil and gas reservoirs is provided.

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