Modeling the transient behavior of BHA/drill string while drilling
AssigneeSchlumberger Technology Corporation
InventorsJahir Pabon, Nathan Wicks, Yong Chang, Clinton Chapman, Vivek Singh
Life of this patent
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Abstract
A method, system and computer program product for performing a drilling operation for an oil field, the oil field having a subterranean formation with geological structures and reservoirs therein. The method involves creating a finite-difference model to simulate behavior of a drilling assembly used to drill a wellbore in the drilling operation, performing a simulation of the drilling operation using the finite-difference model, analyzing a result of the simulation, and selectively modifying the drilling operation based on the analysis.
Claims30
A method for performing a drilling operation for an oil field, the oil field having a subterranean formation with geological structures and reservoirs therein, comprising:
- creating a finite-difference model to simulate behavior of a drilling assembly used to drill a wellbore in the drilling operation by:
- modeling the wellbore as a visco-elastic boundary with friction;
- and
- modeling interaction of a drill bit of the drilling assembly with rock along the wellbore using structural compliance of the tool under compressive loading and a modified Hertzian contact formulation in which contact area, reaction forces, and torque are non-linearly dependent on depth of cut, rock strength, and drill bit geometry, wherein the depth of cut is calculated using actual bit cutting advance per revolution;
- performing a simulation of the drilling operation using the finite-difference model;
- analyzing a result of the simulation to generate an analysis;
- and
- generating, using a computer processor, a modified drilling operation by selectively modifying the drilling operation within the finite-difference model based on the analysis.
A method of performing a drilling operation for an oil field, the oil field having a subterranean formation with geological structures and reservoirs therein, comprising:
- creating a model to simulate behavior of a drilling assembly used to drill a wellbore in the drilling operation by:
- modeling the wellbore as a visco-elastic boundary with friction;
- and
- modeling interaction of a drill bit of the drilling assembly with rock along the wellbore using structural compliance of the tool under compressive loading and a modified Hertzian contact formulation in which contact area, reaction forces, and torque are non-linearly dependent on depth of cut, rock strength, and drill bit geometry, wherein the depth of cut is calculated using actual bit cutting advance per revolution;
- performing a simulation of the drilling operation with a set of different states using the model;
- analyzing a result of the simulation to generate an analysis;
- and
- generating, using a computer processor, a modified drilling operation by selectively modifying, within the model, at least one of the drilling operation and the drilling assembly based on the analysis.
A method of performing a drilling operation for an oil field, the oil field having a subterranean formation with geological structures and reservoirs therein, comprising:
- creating a model of a drilling assembly, wherein the model is used to simulate behavior of the drilling assembly during drilling of a wellbore in the drilling operation within a selected tolerance when compared to using the drilling assembly to actually drill the wellbore in the drilling operation, wherein creating a model includes:
- modeling the borehole as a visco-elastic boundary with friction;
- and
- modeling interaction of a drill bit of the drilling assembly with rock along the wellbore using structural compliance of the tool under compressive loading and a modified Hertzian contact formulation in which contact area, reaction forces, and torques are non-linearly dependent on depth of cut, rock strength and drill bit geometry, wherein the depth of cut is calculated using actual bit cutting advance per revolution;
- performing a simulation of the drilling operation using the model;
- analyzing a result of the simulation to generate an analysis;
- and
- generating, using a computer processor, a modified drilling operation by selectively modifying, within the model, at least one of the drilling operation and the drilling assembly based on the analysis.
A non-transitory computer usable medium having computer usable program code for performing a drilling operation for an oil field, the oil field having a subterranean formation with geological structures and reservoirs therein, the computer usable program code when executed causing a computer processor to:
- create a finite-difference model to simulate a drilling assembly drilling a wellbore in a drilling operation by:
- modeling the wellbore as a visco-elastic boundary with friction;
- and
- modeling interaction of a drill bit of the drilling assembly with rock along the wellbore using structural compliance of the tool under compressive loading and a modified Hertzian contact formulation in which contact area, reaction forces, and torque are non-linearly dependent on depth of cut, rock strength, and drill bit geometry, wherein the depth of cut is calculated using actual bit cutting advance per revolution;
- perform a simulation of the drilling operation using the finite-difference model;
- analyze a result of the simulation to generate an analysis;
- and
- generate a modified drilling operation by selectively modifying the drilling operation within the finite-difference model based on the analysis.
A non-transitory computer usable medium having computer usable program code for performing a drilling operation for an oil field, the oil field having a subterranean formation with geological structures and reservoirs therein, the computer usable program code when executed causing a computer processor to:
- create a model to simulate behavior of a drilling assembly used to drill a wellbore in the drilling operation by:
- modeling the wellbore as a visco-elastic boundary with friction;
- and
- modeling interaction of a drill bit of the drilling assembly with rock along the wellbore using structural compliance of the tool under compressive loading and a modified Hertzian contact formulation in which contact area, reaction forces, and torque are non-linearly dependent on depth of cut, rock strength, and drill bit geometry, wherein the depth of cut is calculated using actual bit cutting advance per revolution;
- perform a simulation of the drilling operation with a set of different states using the model;
- analyze a result of the simulation to generate an analysis;
- and
- generate a modified drilling operation by selectively modifying, within the model, at least one of the drilling operation and the drilling assembly based on the analysis.
A system for performing a drilling operation for an oil field, the oil field having a subterranean formation with geological structures and reservoirs therein, comprising:
- a computer processor;
- a modeling unit executing on the computer processor to create a finite-difference model to simulate behavior of a drilling assembly used to drill a wellbore in the drilling operation by:
- modeling the wellbore as a visco-elastic boundary with friction;
- modeling interaction of a drill bit of the drilling assembly with rock along the wellbore using structural compliance of the tool under compressive loading and a modified Hertzian contact formulation in which contact area, reaction forces, and torque are non-linearly dependent on depth of cut, rock strength, and drill bit geometry, wherein the depth of cut is calculated using actual bit cutting advance per revolution;
- and
- generate a modified drilling operation by selectively modifying the drilling operation within the finite-difference model based on an analysis
- a simulation unit operatively connected to the modeling unit for performing a simulation of the drilling operation using the finite-difference model;
- and
- an analyzer operatively connected to the modeling unit for analyzing a result of the simulation to generate the analysis.
Dependencies are inferred from the claim text.