An improved model for predicting high-rate cased-hole gravel-pack well performance

摘要

In this paper, an improved analytical model for predicting high-rate gravel-packed well performance is presented. The ecommended model is based on serial flow through the perforation tunnels filled with formation sand and gravel, and has been calibrated with field data from three major oil fields in the Norwegian sector of the North Sea. The effective tunnel permeability is found to be a function of original formation permeability and gravel size. A new correlation for the highvelocity coefficient as a function of effective tunnel permeability is also given. The model, combined with the new correlations, gives a satisfactory match between measured and calculated pressure drop. A guideline for predicting pressure drop in high-rate cased-hole gravel-packed wells is presented, aiming at improving the tools for performance prediction for future wells. With these tools, specific targets can be identified for improvements in wells, thereby ultimately increasing well production and field profitability.