Simulating Downhole Flow Through a Perforation

• US 20110271751A1
• Filed: 05/06/2010
• Published: 11/10/2011
• Est. Priority Date: 05/06/2010
• Status: Active Grant

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Haggerty, Dennis, Brooks, James E.
• Granted Patent: US 8,549,905 B2
• Time in Patent Office: Days
• US Class Current: 73/152.07
• CPC Class Codes: E21B 43/11 Perforators; Permeators
• CPC Class Codes: E21B 49/02 by mechanically taking samples of the soil
• CPC Class Codes: G01V 11/002 Details, e.g. power supply systems for logging instruments, transmitting or recording data, specially adapted for well logging, also if the prospecting method is irrelevant means for transmitting well survey signals E21B47/12; signal transmission systems in general G08C; transmission in general H04B

Abstract

A method of testing a core sample is provided. The method comprises determining an impedance map, attaching a sleeve to the core sample, and measuring a flow performance of the core sample. An impedance of each of a plurality of portions of the sleeve is based on the impedance map.

Claims

1. A method of testing a core sample, comprising:

determining an impedance map;

attaching a sleeve to the core sample, wherein a flow impedance of each of a plurality of portions of the sleeve is based on the impedance map; and

measuring a flow performance of the core sample.

2. The method of claim 1, wherein the impedance map is determined based on at least one of a formation parameter, a perforation parameter, a wellbore parameter, and a core sample parameter.

3. The method of claim 2, wherein the formation parameter comprises one of a rock permeability, a rock type, an overburden pressure, a formation pressure, a reservoir diameter, and a reservoir height;

wherein the perforation parameter comprises one of a penetration length, a penetration shape, a penetration damage, a shot density, and a gun phasing;

wherein the wellbore parameter comprises one of a wellbore diameter, a wellbore pressure, a casing thickness, a casing material, a cement thickness, and a cement type; and

wherein the core sample parameter comprises one of a core sample length and a core sample diameter.

4. The method of claim 1, wherein portions of the sleeve that are equal distance from an end of the core sample have the same flow impedance.

5. The method of claim 4, further comprising:

determining an elliptical cross section based on a rock permeability; and

shaping the core sample to have the determined elliptical cross section.

6. The method of claim 1, wherein at least two portions of the sleeve that are equal distance from an end of the core sample have different flow impedance and wherein at least two portions of the sleeve that are at different distances from an end of the core sample have different flow impedance.

7. The method of claim 1, further comprising:

determining a pressure differential associated to each of the portions of the sleeve based on at least one of a formation parameter, a perforation parameter, a wellbore parameter, and a core sample parameter;

determining a flow velocity associated to each of the portions of the sleeve based on at least one of a formation parameter, a perforation parameter, a wellbore parameter, and a core sample parameter, and

wherein the impedance map is determined at least in part based on the pressure differentials associated to each of the portions of the sleeve and based on the flow velocities associated to each of the portions of the sleeve.

8. The method of claim 1, further comprising modifying a pressure transient that occurs after the core sample is perforated, where the pressure transient is modified by fluid flow into an interior of a surge device, wherein the surge device comprises a piston, an interior chamber, and a crushable spring, wherein the piston mass, the volume of the interior chamber, and the spring constant of the crushable spring are designed to produce the modified pressure transient.

9. A perforation test target, comprising:

a metal plate;

a core sample adhered to the metal plate at one end; and

a first sleeve adhered to the core sample, wherein a flow impedance of each of a plurality of portions of the first sleeve is based on a predetermined impedance map.

10. The perforation test target of claim 9, wherein the first sleeve is comprised of layers of filter paper, wherein the number of layers at each portion of the first sleeve corresponds to the flow impedance at that portion.

11. The perforation test target of claim 9, wherein the first sleeve is comprised of ceramic material, wherein the geometry of the first sleeve is based on the predetermined impedance map.

12. The perforation test target of claim 9, further comprising a second sleeve positioned over the first sleeve, wherein a compliance of the second sleeve varies along a circumference of the core sample.

13. The perforation test target of claim 9, wherein the perforation test target further comprises a cap adhered to an end of the core sample opposite the metal plate, wherein the cap has a flow impedance based at least on one of a formation parameter, a perforation parameter, a wellbore parameter, and a core sample parameter.

14. A system for testing a core sample, comprising:

a non-permeable sleeve placed over the core sample;

a first pair of opposing actuators to apply opposing force to the non-permeable sleeve in a first axis normal to the axis of the core sample;

a second pair of opposing actuators to apply opposing force to the non-permeable sleeve in a second axis normal to the axis of the core sample and normal to the first axis;

a wellbore pressure reservoir to provide simulated wellbore pressure; and

a formation pressure reservoir to provide simulated formation fluid pressure.

15. The system of claim 14, wherein the first pair of opposing actuators and the second pair of opposing actuators are hydraulic actuators.

16. The system of claim 14, wherein the first pair of opposing actuators and the second pair of opposing actuators are electrical actuators.

17. The system of claim 14, wherein the force applied by the first pair of opposing actuators and the second pair of opposing actuators are separately controlled, wherein the force applied to the core sample by the first pair of opposing actuators is based on a vertical overburden pressure, and wherein the force applied to the core sample by the second pair of opposing actuators is based on a horizontal overburden pressure.

18. The system of claim 14, further comprising a core sample, wherein the core sample has the shape of an elliptic cylinder.

19. The system of claim 14, further comprising a permeable sleeve adhered to the core sample, wherein the non-permeable sleeve is positioned over both the permeable sleeve and the core sample, wherein a flow impedance of each of a plurality of portions of the permeable sleeve is based on an impedance map, wherein the impedance map is determined based on at least one of a formation parameter, a perforation parameter, a wellbore parameter, and a core sample parameter.

20. The system of claim 19, wherein the permeable sleeve is comprised of one of filter material, filter cake, and ceramic.