Cavitation-based hydro-fracturing simulator

Patent metadata

Field	Value
Publication number	US-9500068-B2
Application number	US-201414224414-A
Country	US
Kind code	B2
Filing date	Mar 25, 2014
Priority date	Nov 12, 2010
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

An apparatus 300 for simulating a pulsed pressure induced cavitation technique (PPCT) from a pressurized working fluid (F) provides laboratory research and development for enhanced geothermal systems (EGS), oil, and gas wells. A pump 304 is configured to deliver a pressurized working fluid (F) to a control valve 306 , which produces a pulsed pressure wave in a test chamber 308 . The pulsed pressure wave parameters are defined by the pump 304 pressure and control valve 306 cycle rate. When a working fluid (F) and a rock specimen 312 are included in the apparatus, the pulsed pressure wave causes cavitation to occur at the surface of the specimen 312 , thus initiating an extensive network of fracturing surfaces and micro fissures, which are examined by researchers.

First claim

What is claimed is:

1. An apparatus for generating a pulsed pressure induced cavitation technique from a pressurized working fluid to simulate the hydrofracturing of a specimen when the working fluid and the specimen are installed in the apparatus, the apparatus comprising:
a pump that is fluidly coupled between a reservoir and a control valve, said control valve having an open position and a closed position, said pump capable of raising the pressure of the working fluid at said control valve;
a test chamber for holding the installed specimen, said test chamber being fluidly coupled to said control valve and receiving the working fluid from said control valve when said control valve is in the open position; and
wherein the control valve includes an outer housing having an upstream end defining both an inlet aperture that is fluidly coupled to the pump and a pressure chamber, the pressure chamber accepting the pressurized working fluid via the inlet aperture, and a downstream end defining a pulse cavity for discharging the pressurized working fluid to a fluidly coupled test chamber, and a medial portion defining a stationary bulkhead disposed between the pressure chamber and the pulse cavity and defining one or more bulkhead apertures that fluidly couple the pressure chamber to the pulse cavity, a rotatable shutter that is disposed inside the pressure chamber and adjacent to the bulkhead, the shutter defining one or more windows and being affixed to a shaft, supported by the bulkhead, and extending through the pressure chamber, the shaft exiting the outer housing through its upstream end, a powering device coupled to the shaft and wherein rotation of the shaft by the powering device causes the windows in the shutter to alternately align and misalign with the one or more bulkhead apertures, causing the pressurized working fluid in the pressure chamber to flow through the apertures in the bulkhead, through the pulse cavity, and into the test chamber as pressure pulses, causing cavitation to occur at the specimen.

2. The apparatus of claim 1 and further comprising:
a pressure regulator that is fluidly coupled between said test chamber and said reservoir.

3. The apparatus of claim 1 and further comprising:
a pressure accumulator that is fluidly coupled between said pump and said control valve.

4. The apparatus of claim 1 wherein the test chamber comprises:
a cylindrical pressure chamber defined by an outer housing and having a upstream end that is fluidly coupled to said control valve and a downstream end that is fluidly coupled to said reservoir and where the specimen is disposed inside said chamber when it is installed in the apparatus.

5. The apparatus of claim 4 and further comprising a heating element at least partially surrounding the test chamber.

6. The apparatus of claim l wherein the powering device is an electric motor.

7. The apparatus of claim 1 and further comprising a heater surrounding the test chamber.

8. The apparatus of claim 1 and further comprising a working fluid installed in the apparatus and wherein the working fluid is water.

9. The apparatus of claim 6 wherein the period between pulses of the pressurized working fluid is determined by the number of shutter windows, the number of bulkhead apertures, and the rotational speed of said powering device.

10. The apparatus of claim 8 wherein the pressure of the working fluid at the test chamber is greater than or equal to approximately 300 psi (2068.4 kPa) and less than or equal to approximately 2,000psi (13,789.5 kPa).

11. The apparatus of claim 1 comprising two bulkhead apertures and four shutter windows.

12. The apparatus of claim 6 wherein the powering device rotates the shaft between approximately 300 revolutions per minute and approximately 60,000revolutions per minute.

13. The apparatus of claim 8 and further comprising a specimen installed in the test chamber.

Assignees

• Ut Battelle Llc

Inventors

• Wang Jy-An John
• Wang Hong
• Ren Fei
• Cox Thomas S

Classifications

• G01N3/567 Primary

  by submitting the specimen to the action of a fluid or of a fluidised material, e.g. cavitation, jet abrasion (G01N3/565 takes precedence) · CPC title

• E21B43/26 Primary

  by forming crevices or fractures · CPC title

• G01N29/2418

  using optoacoustic interaction with the material, e.g. laser radiation, photoacoustics (photoacoustic cells G01N21/1702; measuring characteristics of vibrations by using radiation-sensitive means G01H9/00; acousto-optical conversion techniques for short-range imaging G01S15/8965; sound-producing devices using laser bundle G10K15/046) · CPC title

• B23K26/122

  in a liquid, e.g. underwater · CPC title

• G01N2203/0055

  using mechanical waves, e.g. acoustic · CPC title