A generalized numerical framework to simulate gravel packing in typical wellbore completions is proposed. Given the well, downhole tool string configuration, fluid and gravel properties, and pump schedule, the simulator predicts the time evolution of the pressure, fluid and gravel fluxes and concentrations along the wellbore. The time evolution of the gravel concentration provides the packing pattern and the end of job pack state. This is achieved by solving the one dimensional (1D), mass and momentum conservation equations for the fluid and gravel in a staggered manner. A 1D. piecewise linear, finite element method is used to discretize the governing equations along the wellbore. The architecture of the framework is general enough to handle typical wellbore completions and gravel packing tool string configurations. This is achieved by modeling wellbore components as generalized forms of nodes, linear elements (with or without cross flow), and sources/sinks. This description allows different gravel packing completion configurations to be modeled generally without resorting to a separate and explicit model of each type of tool. At each time step, the whole system is assembled, and the nonlinear system is solved using robust and performant non-linear and sparse linear solvers. The software heavily leverages object-oriented design and high-performance computing practices. Finally, the simulator is used to show the efficacy of the Alternate path technology shunt tubes in achieving complete gravel pack in a long horizontal well. This is shown by simulating cases where significant leak-off would result in a premature bridge in the absence of the shunt tubes. This generalized approach should allow for a flexible extension to simulating gravel packing using other wellbore completions such as washpipe diverter valves, screens with inflow control devices.
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