Fundamentals of sand control fluid flows

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In an era of hydrocarbon depletion, it is inevitable that resource development will focus increasingly on less consolidated and difficult reservoirs. In the past 15-20 years "sand control" has become a growing and significant part of the portfolio of well completion services used in the oil and gas industry. To prevent reservoir solids from causing production blockages and to partially support the surrounding reservoir mechanically, it is common to pack the well with graded solid particles (usually sand, or specially designed ceramics): so called gravel-packing. The proposed project focuses on some of the fundamental physical processes that need to be understood in order that open hole completions can be reliably designed and executed. The project is organized in 2 sub-projects.(Sub-project I). First, we intend to study standard water gravel-packing techniques. This type of packing accounts for a large percentage of current gravel-packed completions in horizontal wells. We will re-examine current mechanical models for the process, which focus largely on steady flows, improve the physical models for the local behaviour of the slurry and develop a transient process model. The main objective is to quantify current operations and understand the physical reasons for current limitations and failures in a way that is adaptable to new operational scenarios.(Sub-project II). Second, we intend to study viscous slurries in alternate path configurations where fluids are diverted to smaller, secondary ducts (shunt tubes) through which blockages may be bypassed to ensure a uniform gravel pack. Viscous slurries include various non-Newtonian fluids with higher viscosities to aid in particle transport but with frictional losses which are mitigated via viscoelastic turbulent drag-reduction. We intend to work in 2 directions: (a) running high speed flow loop tests to characterize the down-hole flow conditions of these fluids and quantify drag reduction mechanisms; (b) developing rheological models in conjunction with numerical simulation to be able to predict and optimize these flows.