Abstract
In this paper we study the use of Virtual Element method for geomechanics. Our emphasis is on
applications to reservoir simulations. The physical processes that form the reservoirs, such as
sedimentation, erosion and faulting, lead to complex geometrical structures. A minimal representation,
with respect to the physical parameters of the system, then naturally leads to general polyhedral grids.
Numerical methods which can directly handle this representation will be highly favorable, in particular in
the setting of advanced work-flows. The Virtual Element method is a promising candidate to solve the
linear elasticity equations on such models. In this paper, we investigate some of the limits of the VEM
method when used on reservoir models. First, we demonstrate that care must be taken to make the method
robust for highly elongated cells, which is common in these applications, and show the importance of
calculating forces in terms of traction on the boundary of the elements for elongated distorted cells.
Second, we study the effect of triangulations on the surfaces of curved faces, which also naturally occur in
subsurface models. We also demonstrate how a more stable regularization term for reservoir application
can be derived.
applications to reservoir simulations. The physical processes that form the reservoirs, such as
sedimentation, erosion and faulting, lead to complex geometrical structures. A minimal representation,
with respect to the physical parameters of the system, then naturally leads to general polyhedral grids.
Numerical methods which can directly handle this representation will be highly favorable, in particular in
the setting of advanced work-flows. The Virtual Element method is a promising candidate to solve the
linear elasticity equations on such models. In this paper, we investigate some of the limits of the VEM
method when used on reservoir models. First, we demonstrate that care must be taken to make the method
robust for highly elongated cells, which is common in these applications, and show the importance of
calculating forces in terms of traction on the boundary of the elements for elongated distorted cells.
Second, we study the effect of triangulations on the surfaces of curved faces, which also naturally occur in
subsurface models. We also demonstrate how a more stable regularization term for reservoir application
can be derived.
