Simulating Multi-phase Flow in Fractured Reservoirs

Abstract

A method for performing fluid extraction from a fractured subsurface formation includes receiving a discrete fracture model representing the fractured subsurface formation and receiving pressure values and saturation values for multiple fluid phases across the discrete fracture model. Based on the pressure values for the multiple fluid phases across the discrete fracture model, face-centroid velocities are generated for the cells and the pressure values for the multiple fluid phases are updated by performing operations including a mimetic finite difference analysis. Based on the generated face-centroid velocities, an exit face and time-of-flight is determined for each cell and the saturation values are updated for the multiple fluid phases across the discrete fracture model based on the exit face and time-of-flight for each cell.

What is claimed is: 
     
         1 . A method for performing hydrocarbon extraction from a fractured subsurface formation, the method comprising:
 receiving a discrete fracture model representing the fractured subsurface formation, the discrete fracture model comprising matrix cells and fracture cells;   receiving pressure values and saturation values for multiple fluid phases across the discrete fracture model;   based on the pressure values for the multiple fluid phases across the discrete fracture model, generating face-centroid velocities and for the matrix cells and the fracture cells and updating the pressure values for the multiple fluid phases across the discrete fracture model by performing operations including a mimetic finite difference analysis;   based on the generated face-centroid velocities, determining an exit face and time-of-flight for each cell and updating the saturation values for the multiple fluid phases across the discrete fracture model based on the exit face and time-of-flight for each cell;   storing the pressure values and the saturation values for discrete fracture model and incrementing a time counter;   iteratively repeating the generating, determining, and storing steps until the time counter reaches a set value; and   based on stored the pressure values and the saturation values, controlling pumping from a production well extending into the fractured subsurface formation.   
     
     
         2 . The method of  claim 1 , further comprising measuring the pressure values and the saturation values. 
     
     
         3 . The method of  claim 1 , further comprising generating data from the fractured subsurface formation and generating the discrete fracture model. 
     
     
         4 . The method of  claim 1 , wherein the multiple fluid phases comprise oil and water. 
     
     
         5 . The method of  claim 4 , wherein the multiple fluid phases consist of oil and water. 
     
     
         6 . The method of  claim 1 , wherein receiving pressure values and saturation values comprises receiving previously measured pressure values from a database. 
     
     
         7 . The method of  claim 1 , wherein receiving the discrete fracture model comprises receiving a previously generated discrete fracture model. 
     
     
         8 . The method of  claim 1 , wherein the saturation values are calculated using a streamline-based method. 
     
     
         9 . The method of  claim 8 , wherein the streamline-based method comprises evaluating, for each face of a matrix cell, whether streamlines interest the face being evaluated. 
     
     
         10 . The method of  claim 9 , further comprising identifying which face of the matrix cell being evaluated the streamlines exit through. 
     
     
         11 . A method for performing hydrocarbon extraction from a fractured subsurface formation, the method comprising:
 receiving, by a processor, a discrete fracture model comprising matrix cells and fracture cells representing the fractured subsurface formation;   receiving, by the processor, pressure values and saturation values for multiple fluid phases across the discrete fracture model;   based on the pressure values for the multiple fluid phases across the discrete fracture model, generating, by the processor, face-centroid velocities and for the matrix cells and the fracture cells and updating the pressure values for the multiple fluid phases across the discrete fracture model by performing operations including a mimetic finite difference analysis;   based on the generated face-centroid velocities, determining, by the processor, an exit face and time-of-flight for each cell and updating the saturation values for the multiple fluid phases across the discrete fracture model based on the exit face and time-of-flight for each cell;   storing the pressure values and the saturation values for discrete fracture model and incrementing a time counter; and   iteratively repeating the generating, determining, and storing steps until the time counter reaches a set value.   
     
     
         12 . The method of  claim 11 , wherein the multiple fluid phases comprise oil and water. 
     
     
         13 . The method of  claim 12 , wherein the multiple fluid phases consist of oil and water. 
     
     
         14 . The method of  claim 12 , wherein receiving pressure values and saturation values comprises receiving previously measured pressure values from a database. 
     
     
         15 . The method of  claim 14 , wherein receiving the discrete fracture model comprises receiving a previously generated discrete fracture model. 
     
     
         16 . The method of  claim 15 , wherein the saturation values are calculated using a streamline-based method. 
     
     
         17 . The method of  claim 16 , wherein the streamline-based method comprises evaluating, for each face of a matrix cell, whether streamlines interest the face being evaluated. 
     
     
         18 . The method of  claim 17 , further comprising identifying which face of the matrix cell being evaluated the streamlines exit through.