Aquifer Definition

The presence of aquifers has a large influence on the amount of hydrocarbons that can be recovered, and thus should be part of the simulation. In an ideal world, the simulation grid would encompass the aquifer region, but due to limits on computing resources an analytical model for the aquifer is often used.

This model is coupled to the cells on the outside of the simulation model. With respect to the simulation model, they act as dynamical boundary conditions. The boundary conditions are dynamical since the flow into a cell depends on the pressure difference between a cell and the aquifer, and the total flow into the connected cells reduces the pressure of the aquifer.

Key parameters appearing in the simulator deck to define an aquifer are the total coupling of the aquifer to the grid, the relative contributions of individual grid cells, or the directions of the faces that couple to the aquifer, the aquifer pore volume, and the depth of the aquifer. JewelSuite Subsurface Modeling allows you to calculate these key parameters from the simulation grid by making use of an aquifer definition and an aquifer property.

Your aquifer definition can be coupled to a 3D grid and an aquifer property. The aquifer property has value Non Aquifer or Aquifer, identifying which cells are linked to the aquifer.

When the coupling is present, the aquifer can be used to calculate aquifer parameters for a reservoir simulation case using the Aquifer Definition (Simulate > Tools > Aquifer Definition) form, as described below.

  1. To create a new definition, give it a name and press the Create button. The aquifer definition will be visible in the JewelExplorer. An existing aquifer definition can be selected to be used in the rest of the panel or deleted. Deletion can also be done from the JewelExplorer.

    Name  The name of an aquifer definition to be generated.

    Create  Create an aquifer definition with the given name.

    Delete  Delete the selected aquifer definition.

  2. Select the 3D grid for which the aquifer definition will be created.

  3. To create a new aquifer property, give it a name and click the Create button. The property will be visible in the JewelExplorer. You can also select an existing aquifer property to be used in the rest of the panel or to be deleted. Deletion from the JewelExplorer is possible as well. The aquifer property can have the value 'Non Aquifer' or 'Aquifer'. After creation, the property is by default set to 'Non Aquifer'.

    Name  The name of an aquifer property to be generated.

    Create  Create an aquifer property with the given name.

    Delete  Delete the selected aquifer property.

  4. The aquifer property can be populated with cells to be connected to the aquifer. After checking the sides that should be active (J-, J+, I-, I+, and/or Bottom), the layers can be chosen and the aquifer property can be filled.

After you have created an aquifer and defined aquifer properties, you can connect them to your simulation models. While simulating IMEX, GEM or STARS models, you can do this on the Aquifers form (Simulate > IMEX/GEM/STARS > Workflow > Aquifers). For Eclipse, you can do this on the Aquifers form (Simulate > Eclipse > Workflow > Aquifers).