Method for producing full field radial grid for hydrocarbon reservoir simulation

A method for establishing a grid for simulating a geologic reservoir structure comprising the steps of,

• establishing an outer boundary for an area of said geologic structure,
• defining a plurality of well points within said area of said outer boundary, each of said points corresponding to a wellbore into said geologic structure,
• distributing a set of trial concentric circles about each of said well points,
• a) beginning with a first well point, identify intersection circles of the set of trial concentric circles about said first well point, where an intersection circle is defined as an outer radius circle about a well point that intersects either said outer boundary or a circle of a trial circle of another set of trial concentric circles about other well points, and find the intersection points with said outer boundary and with any circle about any other well point,
• b) recording final concentric circles of said trial concentric circles if a trial connection circle is not identified as an intersection circle,
• c) determining the location of intersection points of said first intersection circle with said outer boundary,
• d) establishing radial lines from said well point to a plurality of said intersection points,
• e) determining the location of circle-to-circle intersection points of said intersection circles with one or more circles around another well point,
• f) recording arcs of any intersection circle that is not within another circle and not outside said outer boundary, and
• g) establishing additional grid radial lines from said first well to each of said circle-to-circle intersection points,
• h) repeating steps a) through g) for each other well point,
• wherein said area within said outer boundary is divided into a grid of cells.

A method for establishing a field scale radial grid for simulating a geologic reservoir structure comprising the steps of,

• establishing a boundary for an area of said geologic structure,
• defining a plurality of well points within said area of said boundary, each of said points corresponding to a wellbore within said geologic structure,
• distributing a set of trial concentric circles about each of said well points, where said trial concentric circles are characterized by increasing circle numbers away from said well points and by radii which increase in length with circle numbers away from said well point,
• determining boundary intersection points of said circles around each of said well points with said boundary,
• determining circle intersection points of said concentric circles of each well with circles around other well points,
• select circles which do not have boundary intersection point or circle intersection points,
• selecting arcs of intersecting concentric circles as grid cell boundaries,
• selecting radial lines from a well point to said circle intersection points of its surrounding circles with surrounding circles of other well points as grid lines,
• selecting radial lines from a well point to the boundary intersection points of its surrounding circles with said boundary as grid lines,
• wherein said area within said boundary is divided into a grid of cells.