Method of hydrocarbon reservoir simulation using streamline conformal grids

A non-transitory computer readable medium storing instructions for simulating fluid flow in a hydrocarbon reservoir, the instructions executable by a computer processor, comprising functionality for:

• obtaining a coarse grid model of the hydrocarbon reservoir and a trajectory of a wellbore that penetrates the hydrocarbon reservoir;
• determining a fluid pressure distribution using the coarse grid model;
• determining an initial grid surrounding the trajectory,
• wherein a first axis of the initial grid approximates isobars of the fluid pressure distribution, and
• wherein a second axis of the initial grid approximates streamlines of the fluid pressure distribution;
• constructing a reservoir simulation grid, wherein the reservoir simulation grid:
• conforms to the initial grid in a first region in a vicinity of the wellbore,
• wherein the first region is interior to a bounding box, and
• conforms to the coarse grid model in a second region,
• wherein the second region is exterior to the bounding box;
• and
• wherein the reservoir simulation grid in the first region and the reservoir simulation grid in the second region are connected by an irregular transitional grid;
• and
• performing a hydrocarbon reservoir simulation, modeling a flow of fluid in the hydrocarbon reservoir based, at least in part, on the reservoir simulation grid.

A system comprising:

• a reservoir simulator, configured to:
• obtain a coarse grid model of a hydrocarbon reservoir and a trajectory of a wellbore that penetrates the hydrocarbon reservoir,
• determine a fluid pressure distribution using the coarse grid model,
• determine an initial grid surrounding the trajectory,
• wherein a first axis of the initial grid approximates isobars of the fluid pressure distribution;
• and
• wherein a second axis of the initial grid approximates streamlines of the fluid pressure distribution,
• construct a reservoir simulation grid, wherein the reservoir simulation grid:
• conforms to the initial grid in a first region in a vicinity of the wellbore, wherein the first region is interior to a bounding box;
• and
• conforms to the coarse grid model in a second region,
• wherein the second region is exterior to the bounding box;
• and
• wherein the reservoir simulation grid in the first region and the reservoir simulation grid in the second region are connected by an irregular transitional grid,
• perform a hydrocarbon reservoir simulation, modeling a flow of fluid in the hydrocarbon reservoir based, at least in part, on the reservoir simulation grid;
• develop a hydrocarbon reservoir production plan based, at least on part, upon the hydrocarbon reservoir simulation;
• and
• a well planning system configured to determine a planned wellbore trajectory based upon the hydrocarbon reservoir production plan.