Technique and test facility for conducting flow tests simulating a gravel filter in a laboratory environment under borehole conditions

Abstract

Test gravel packing assembly (460) comprising: a housing (461) having a first surface (462) and a second opposing surface (463), the first surface (462) and the second opposing surface (463) defining a thickness (t) that simulates a desired gravel pack thickness in the borehole; an opening (465) extending completely through the housing (461) from the first surface (462) to the second opposite surface (463), the opening (465) having a single diameter (d6) simulating a desired wellbore casing perforation diameter in the wellbore; and a proppant screen (475) coupled adjacent to the first surface (462) and above the opening (465).

Description

GENERAL STATE OF THE ART

[0001] To design the perforation tool and / or a borehole perforation method, one or more rock cores considered representative of the subterranean formation to be perforated can be tested above ground in a test laboratory to determine some parameters of the subterranean formation and / or interactions between the explosive charges and the subterranean formation. The evaluations of the test results can be used to design the perforation tool and / or the borehole perforation method. An improved method and test facility representative of rock cores are needed in the field.

[0002] US 2014 / 0 319 080 A1, US 2008 / 0 236 891 A1, US 2016 / 0 290 909 A1 and US 8 312 920 B2 constitute prior art for the present invention.

[0003] The invention is defined by the independent claims. SHORT DESCRIPTION

[0004] Reference is now made to the following descriptions in conjunction with the accompanying figures, in which: The Fig. 1-3 illustrate various embodiments of a rock core flow test system manufactured and designed in accordance with the disclosure; The Fig. 4A-4C illustrate various configurations of gravel filter test assemblies manufactured and designed in accordance with embodiments of the disclosure; Fig. Figure 5 illustrates an enlarged view of the gravel filter test arrangement from the dotted field C shown in Fig. 4C is illustrated; The Fig. 6 and Fig. 7 illustrate a laboratory device for simulating a gravel filter and a cap, respectively, made and designed in accordance with the disclosure; Fig. 8 illustrates a method for performing a rock core flow functional test according to an embodiment of the disclosure; and Fig. 9 illustrates a process flow including steps 840, 850 and 860 of Fig. 8 expanded to sub-steps. DETAILED DESCRIPTION

[0005] It should be understood in advance that, although illustrative implementations of one or more embodiments are discussed below, the disclosed systems and methods may be implemented using any number of techniques, whether currently known or existing. The disclosure should not be limited in any way to the illustrative implementations, drawings, and techniques shown below, but may be modified within the scope of the appended claims, along with their full scope of equivalents.

[0006] Unless otherwise specified, the use of any form of the terms "connect," "engage," "couple," "attach," or any other term describing an interaction between elements is not intended to limit the interaction to direct interaction between the elements and may also include indirect interaction between the elements being described. For descriptive purposes, reference is made to upward or downward as "upward," "upper," "upward," or "upstream," that is, toward the surface of the wellbore, and "downward," "lower," "downward," and "downstream," that is, toward the termination end of the wellbore, regardless of the orientation of the wellbore.The term "zone" or "oil-bearing zone" as used herein refers to discrete portions of the wellbore intended for treatment or production, and may refer to an entire hydrocarbon formation or discrete portions of a single formation, such as horizontally and / or vertically spaced portions of the same formation. The various features mentioned above, as well as other features and characteristics described in more detail below, will be readily apparent to those skilled in the art from this disclosure upon reading the following detailed description of the embodiments and by reference to the accompanying drawings.

[0007] Rock core testing can be conducted to evaluate and adjust perforating gun design parameters and perforation process parameters. Tests can be conducted based on the American Petroleum Institute (API) Recommended Practices for Evaluation of Well Perforators Reference Procedure 19B (API RP 19B), First Edition, November 2000. Tests are typically performed on a rock core considered representative of the subterranean formation. For example, rock sections from a subterranean formation taken from the wellbore to be perforated are collected and analyzed to determine the properties of the subterranean formation rock. A cut rock is selected based on the similarity of its properties to the properties of the rock sections from the subterranean formation.In one example, the excised rock is trimmed to a shape suitable for core testing, such as a circular cylinder with a diameter of approximately 18 centimeters (e.g., just over 7 inches) and an axial length of approximately 70 centimeters (e.g., just over 27 inches). The length of the rock core sample may be a different length, as discussed in more detail below, depending on the perforation tunnel depth expected to be created by the perforation charge. In some cases, a rock core sample can be taken from the borehole and used for rock core testing, but such core samples are expensive to obtain and increasingly scarce.

[0008] The present disclosure contemplates conducting at least a portion of the rock testing using high-pressure conditions that may be encountered in some downhole environments. These high-pressure core tests present design challenges. In one or more embodiments, the rock core sample is flow-tested under high pressure without perforation; the rock core sample is flow-tested after perforation during a simulated perforation event; and / or under a simulated high-pressure gravel filter scenario; and a metric relating the various flows is calculated to determine whether the perforation improved flow and the effect of the gravel filter on flow characteristics.If perforation has not improved flow or the gravel filter negatively impacts flow characteristics, the perforation gun design or gravel filter method can be adjusted accordingly. The metric can also be used to compare a variety of different perforation gun designs to select the perforation gun design that performs best in the rock core test. In one or more embodiments, the evaluation of the flow results is based on a pressure measured at an axial borehole face of the rock core, rather than directly measuring the fluid flow rate.

[0009] The rock core may be placed in a containment or pressure vessel that is sealed at one end, for example, by a quick-opening flow control device such as a rupture disk. The rock core may be placed in a sleeve or tube, and an outer surface of the sleeve or tube, in certain embodiments, may be subjected, at least along a portion of its surface (e.g., along its radial surface), to a high overburden or confining pressure, for example, an overburden pressure above about 5,000 pounds per square inch (PSI), above about 10,000 PSI, above about 15,000 PSI, above about 20,000 PSI, above about 25,000 PSI, above about 30,000 PSI, above about 35,000 PSI, above about 40,000 PSI, above about 45,000 PSI, or above about 50,000 PSI.The application of pressure to the sleeve or tubing can be referred to as indirect pressure, which is based on the lack of direct contact between the fluid exerting the overburden pressure and the rock core. The overburden or confining pressure can be considered a simulation of the pressure experienced in the wellbore environment.

[0010] An axial end of a subterranean formation or an axial pore end of the rock core may be subjected to a fluid having a high pressure above about 5,000 pounds per square inch (PSI), above about 10,000 PSI, above about 15,000 PSI, above about 20,000 PSI, above about 25,000 PSI, above about 30,000 PSI, above about 35,000 PSI, above about 40,000 PSI, above about 45,000 PSI, or above about 50,000 PSI, but in one embodiment, below the overburden or confining pressure. In some contexts, the pressure exerted on the axial pore end of the rock core may be referred to as flow pressure, which is based on the direct contact between the fluid and the rock core.

[0011] The downhole end of the rapid-opening flow control device may be subjected to a high pressure above about 5,000 pounds per square inch (PSI), above about 10,000 PSI, above about 15,000 PSI, above about 20,000 PSI, above about 25,000 PSI, above about 30,000 PSI, above about 35,000 PSI, above about 40,000 PSI, above about 45,000 PSI, or above about 50,000 PSI, but in one embodiment, below the overburden pressure. The pressure on the axial pore end of the rock core and the pressure on the downhole end of the rapid-opening flow control device may be increased simultaneously so that they remain substantially the same up to a first pressure.

[0012] In one embodiment, the first pressure at the axial pore end of the rock core is maintained while the pressure on the downhole side of the fast-opening flow control device is reduced until a pressure differential between the pressure at the axial pore end of the rock core and the pressure at the downhole end of the fast-opening flow control device exceeds a predefined threshold, for example, a pressure differential of approximately 2,000 PSI. It is understood that when the fast-opening flow control device is closed (thus no fluid flows through the rock core sample), the pressure exerted on the axial pore end of the rock core is equalized across the rock core sample, and the pressure exerted on the axial pore end of the rock core is equal to the pressure exerted on a core-facing side of the fast-opening flow control device.When the pressure differential exceeds the predefined threshold, the fast-opening flow control device opens quickly, e.g., the rupture disc ruptures. The pressure on the downhole side of the fast-opening flow control device when the device is activated or opened may be referred to as the second pressure. The second pressure is less than the first pressure. After the fast-opening flow control device is activated, the rock core sample experiences flow, and the pressure on the downhole side of the fast-opening flow control device drops from the second pressure to a third pressure within a first time interval. In combination with the present disclosure, the first pressure, the second pressure, and the third pressure may be selected by one of ordinary skill in the art.In practice, the selection of the first pressure, the second pressure, and the third pressure may be based at least in part on available or conveniently manufactured quick-opening flow control devices. The pressures may also be selected at least in part to simulate downhole conditions as closely as possible.

[0013] After testing the unperforated rock core, a perforation may be formed in the rock core by coupling a perforation assembly (e.g., including an explosive charge) to it. The explosive charge, in certain embodiments, may comprise a shaped explosive, a charge liner, and a metal layer that models a perforation gun tool body in proximity to the explosive charge.

[0014] The rock core and this perforation assembly can then be placed in the container. In this situation, the axial end of the rock core facing the borehole is sealed by the perforation assembly. The rock core can be indirectly re-exposed along at least a portion of its radial surface to a high overcharge pressure, for example, an overcharge pressure above approximately 5,000 pounds per square inch (PSI), 10,000 PSI, 15,000 PSI, 20,000 PSI, 25,000 PSI, 30,000 PSI, 35,000 PSI, 40,000 PSI, 45,000 PSI, or 50,000 PSI (1 PSI = 0.0689476 bar). The axial pore end of the rock core may be subjected to high pressures in excess of approximately 5,000 pounds per square inch (PSI), 10,000 PSI, 15,000 PSI, 20,000 PSI, 25,000 PSI, 30,000 PSI, 35,000 PSI, 40,000 PSI, 45,000 PSI, or 50,000 PSI but below the overburden pressure.

[0015] The downhole end of the perforation assembly may be directly exposed to a high pressure in excess of approximately 5,000 pounds per square inch (PSI), 10,000 PSI, 15,000 PSI, 20,000 PSI, 25,000 PSI, 30,000 PSI, 35,000 PSI, 40,000 PSI, 45,000 PSI, or 50,000 PSI, but below the overburden pressure. The downhole end of the perforation assembly may be directly exposed to a pressure substantially equal to the pressure at which the above-described quick-opening flow control device opened, for example, the second pressure described above.

[0016] The explosive charge can then be fired, and the explosion creates a perforated area in the core sample. As is known to those skilled in the art, the length of the core sample is sized so that the perforated area does not completely penetrate the core. The aforementioned API RP 19B Recommended Practices for Evaluation of Well Perforators recommends that the tunnel extend no further than a distance equal to the diameter from the pore end of the core sample. For example, if the core sample has a diameter of 7 inches and a length of 28 inches, the tunnel created by the explosion should penetrate no more than 21 inches into the core (and thus be 7 inches from the pore end of the core sample).The rock core sample can be examined after the explosion and after the transient pressure test to determine whether this recommendation has been met. For example, a sonogram of the rock core sample can be obtained after the explosion using an ultrasonic analysis tool. If the explosion penetrates too deeply into the rock core, a longer rock core sample can be formed, and one or more of the tests can be repeated using the longer rock core sample.

[0017] After perforation, the rock core experiences flow, and the pressure at the downhole axial end of the rock core drops from the second pressure to the third pressure over a second time interval. The first and second time intervals can be compared to determine a production ratio that promotes evaluation of the effectiveness of the explosive charge design for use with the rock core sample. In one or more embodiments, the volumetric flow of fluid through the rock core sample under high pressure can be determined by collecting an overflow of fluids and weighing the fluid. Under the high-pressure conditions of the rock core tests, the fluid can experience compaction.Accordingly, the volumetric flow rate of fluid through the rock core sample can be determined by determining the uncompacted volume of the fluid based on the measured weight and then converting this uncompacted volume to a compacted volume based on known or determinable compressibility relationships of the fluid in question. Standard flow rate sensors may not be practical in the high-pressure test environment taught by the present disclosure, for example, testing in an environment with pressures above about 25,000 PSI. In one or more embodiments, the rock core sample is flowed with odorless mineral spirits (ODM), while in other embodiments, another fluid may be flowed into the rock core sample.The above description describes fluid flowing from the axial pore end to the axial borehole end of the rock core with essentially no flow across the radial axial surface of the rock core sample, as might be relevant in a production well scenario. However, in one or more embodiments, the core testing method may be modified, and fluid may flow from the axial borehole end to the axial pore end of the rock core sample with essentially no flow across the radial axial surface of the rock core sample, as might be relevant in an injection well scenario.

[0018] After testing the rock core sample having the perforation, the rock core sample having the perforation can be removed from the pressure chamber, and a gravel filter simulation laboratory device can be coupled thereto. The gravel filter simulation laboratory device, according to one embodiment of the disclosure, comprises a housing having two opposing surfaces, wherein the two opposing surfaces include an opening extending therebetween. Since one of the surfaces of the gravel filter simulation laboratory device is coupled to the rock core sample having the perforation, a proppant can be placed from the opposing surface into the opening, thereby substantially filling the opening, and in certain embodiments, backfilled into the perforated area.A screen assembly can then be coupled over the opening to the exposed opposing surface, thereby retaining the proppant in the lab-mounted gravel screen simulation setup. During this phase, the rock core sample containing the perforation, to which the lab-mounted gravel screen simulation setup is attached, simulates a borehole gravel screen scenario.

[0019] The rock core sample to which the gravel filter simulation laboratory device is attached can then be placed in the pressure chamber and subjected again to the pressure tests previously performed on the rock core sample containing the perforation. Accordingly, similar test results as those obtained on the rock core sample containing the perforation can be obtained on the rock core to which the gravel filter simulation laboratory device is coupled. In certain embodiments, it is not necessary or may even be detrimental to perform the pressure tests on the rock core sample containing only the perforation, and therefore this step is omitted.Accordingly, the process would not perform the compression tests on the rock core sample that only has the perforation and would jump from the compression test without the perforation directly to the compression test on the rock core sample that has the perforation and to which the laboratory equipment for simulating a gravel filter is attached.

[0020] It should be understood that in some embodiments, the pressure test employing a quick-opening flow control device may be conducted without the pressure test detonating an explosive charge. In some embodiments, the pressure test detonating the explosive charge may be conducted without the pressure test employing the quick-opening flow control device. In some embodiments, the pressure test simulating the gravel filter scenario may be conducted without the pressure test employing the quick-opening flow control device or the pressure test detonating the explosive charge.

[0021] With reference to Fig. 1, a rock core flow testing system 100 will now be described. Tests of a rock core sample may simply be referred to as core testing. In one or more embodiments, the system 100 includes, among other elements, a rock core sample 102, a receiving vessel 104, a first pump 106, a first high-pressure accumulator 108, a second pump 110, a second high-pressure accumulator 112, and a third pump 114. The system 100 may further include, again among other elements, a first pressure sensor 116, a second pressure sensor 118, a high-speed pressure recorder 120, a quick-opening high-pressure flow controller 122, a scale 124, and a weight recorder 126. In some contexts, the quick-opening high-pressure flow controller 122 may be referred to as a high-speed high-pressure flow controller.Pumps 106, 110, and 114 are capable of providing fluid at high pressure, for example, fluid at pressures above about 5,000 pounds per square inch (PSI), 10,000 PSI, 15,000 PSI, 20,000 PSI, 25,000 PSI, 30,000 PSI, 35,000 PSI, 40,000 PSI, 45,000 PSI, or 50,000 PSI. In one or more embodiments, pumps 106, 110, and 114 may be capable of supplying fluid pressurized up to about 50,000 PSI. Pumps 106, 110, and 114 may be triplex pumps, although other embodiments may utilize a different type of pump.

[0022] It should be understood that the system 100 may include components and equipment not explicitly described herein. For example, a flow distributor (not shown) may be coupled between the rock core sample 102 and the first pump 106 and / or the first accumulator 108. High-pressure tubing may be used to couple components of the system 100 together. Check valves may be used to establish a one-way flow direction in some portions of the system 100. Pressure relief valves may be used to promote safety and / or to promote fluid capture as an indication of fluid flow through the rock core sample 102.

[0023] The system 100 can promote the maintenance of a constant overburden or confining pressure on the radial surface of the rock core sample 102, which is different from the pressure exerted on the axial ends of the rock core sample 102, whereby fluid flow can occur across an axial pore end of the rock core sample 102 and fluid flow across the radial surface of the rock core sample 102 is substantially blocked. In one or more embodiments, a sleeve or tube surrounds the radial surface of the rock core sample 102 and prevents or dampens fluid flow across the radial surface of the rock core sample 102. Pressure exerted on the sleeve, e.g., overburden or confining pressure, is then exerted on the radial surface of the rock core sample 102.Alternatively, in one or more embodiments, the system 100 may promote maintaining the same pressure on the axial pore end of the rock core sample 102 and on the radial surface of the rock core sample 102, wherein fluid flow may occur across both the axial pore end of the rock core sample 102 and the radial surface of the rock core sample 102. In another alternative embodiment, the system 100 may promote sealing the axial pore end of the rock core sample 102 and applying pressure to the radial surface of the rock core sample 102 and flowing fluid across the radial surface of the rock core sample 102. In some contexts, the rock core sample 102 may be referred to as a core sample.However, in other contexts, the term "core sample" may be reserved to distinguish between a rock core extracted from the specific subterranean formation and the borehole for which a perforation gun is to be designed. In some contexts, the receiving vessel 104 may be referred to as a pressure vessel.

[0024] The high-pressure accumulators 108, 112 receive an inflow of fluid resisted by a chamber of the accumulators filled with a compressible substance, such as nitrogen gas. The high-pressure accumulators 108, 112 serve to maintain an operating pressure by supplying a fluid flow and receiving a fluid flow to maintain pressure through fluid flow demand transients. Accordingly, the high-pressure accumulator 108 may be in fluid communication with the axial pore end of a rock core sample, and the high-pressure accumulator 112 may be in fluid communication with the downhole end of the rock core sample. One of ordinary skill in the art is expected to be familiar with the operating principle of such accumulators. It should be noted that, in certain embodiments, the high-pressure accumulators 108, 112 are particularly designed for operation at high pressures exceeding 25,000 PSI.The design features of the high-pressure accumulators 108, 112 that make them suitable for use in high-pressure environments may include the stability of the storage vessel, a shape of the storage vessel, and an initial pressure of the compressible substance contained within the accumulator. For example, in one or more embodiments, the storage vessel may have a substantially spherical shape.

[0025] The fast-opening, high-pressure flow control device 122 is configured to open quickly when a pressure differential across the component exceeds a predefined threshold. For example, the predefined threshold may be about 500 PSI, about 1000 PSI, about 2000 PSI, or another pressure differential. One of ordinary skill in the art will recognize that individual fast-opening flow control devices may exhibit some variation from unit to unit without negating the value of the tests. For example, a particular instance of a fast-opening, high-pressure flow control device 122 configured to open in response to a pressure differential exceeding 500 PSI may actually open when the pressure differential exceeds 450 PSI or may not open until the pressure differential exceeds 550 PSI.Generally, such unit-to-unit variation can be tolerated, or it can be accounted for by post-test analysis of the test data. Alternatively, if the unit-to-unit variation encountered during a core test is excessive, the test results in question can be discarded and the core test repeated.

[0026] It should be understood that in some embodiments, the quick-opening high-pressure flow control device 122 is designed for use in high-pressure environments, such as environments with pressures above approximately 5,000 pounds per square inch (PSI), 10,000 PSI, 15,000 PSI, 20,000 PSI, 25,000 PSI, 30,000 PSI, 35,000 PSI, 40,000 PSI, 45,000 PSI, or 50,000 PSI. In some contexts, the quick-opening high-pressure flow control device 122 may be referred to as a high-speed high-pressure flow control device 122.

[0027] For the purposes of the present disclosure, rapid opening means that the flow control device in question is substantially fully open after a period of time that is small relative to the time interval used to determine the production ratio. For example, in one or more embodiments, the rapid-opening flow control device 122 is at least 80% fully open after the rapid-opening flow control device 122 begins to open prior to 20% of the time interval used to determine the production ratio. Alternatively, in one or more embodiments, the rapid-opening flow control device 122 is at least 80% fully open after the rapid-opening flow control device 122 begins to open prior to 10% of the time interval used to determine the production ratio.

[0028] Alternatively, the fast-opening flow control device 122 may be substantially open in less than about 500 milliseconds (ms), less than about 300 ms, less than about 10 ms, less than about 5 ms, less than about 1 ms, less than about 100 microseconds (µs), less than about 50 µs, less than about 10 µs, less than about 5 µs, or less than about 1 µs. In one or more embodiments, the fast-opening flow control device 122 may be a rupture disc. In another embodiment, the fast-opening flow control device 122 may be a valve held closed by a shear pin or shear disc that predictably fails at a predefined pressure differential across the fast-opening flow control device 122 and, after failure, undergoes a rapid opening in response to urging the pressure differential and associated fluid flow.In another embodiment, a different form of valve may be used to provide the quick-opening flow control device 122.

[0029] The high-speed pressure recorder 120 receives pressure readings from the first pressure sensor 116 and the second pressure sensor 118, which are configured to measure pressure changes in one or both of the first high-pressure accumulator or the second high-pressure accumulator. In one or more embodiments, the high-speed pressure recorder 120 may filter the pressure readings received from the pressure sensors 116, 118 to remove noise and / or other interference from the readings that is not related to pressure. The high-speed pressure recorder 120 may record the received pressure readings at a periodic rate of 1000 Hertz, 10000 Hertz, 100000 Hertz, or another periodic rate. The high-speed pressure recorder 120 may store each pressure measurement as an entry in a file representing the given pressure value and the time associated with the pressure value.In one or more embodiments, the high-speed pressure recorder 120 may capture up to approximately 625,000 readings per second. However, in another embodiment, a different measurement rate may be provided by the high-speed pressure recorder 120. In one or more embodiments, other types of pressure measurements may be stored by the high-speed pressure recorder 120, including, for example, pressure transients measured at a very high measurement rate, as well as static pressure data measured and recorded approximately every 7.5 seconds before and after the fast-opening flow control device 122 opens.

[0030] In one or more embodiments, the high-speed pressure recording device 120 may include a ballistic pressure gauge. The ballistic pressure gauge may generally be configured to measure a plurality of pressure readings based on an input signal. For example, the opening of the quick-opening flow control device 122 (e.g., a rupture disk or perforating charge) may trigger the initiation of the pressure readings at the time of the input signal or after a short delay. In one or more embodiments, the ballistic pressure gauge may measure up to about 50,000 readings, 100,000 readings, 150,000 readings, 160,000 readings, or 200,000 readings, for example, in a period ranging from about 0.001 seconds to about 1 second, about 0.01 seconds to about 0.75 seconds, or about 0.02 seconds to about 0.05 seconds.The ballistic manometer can then be used to measure a fluid flow greater than about 50 ml / min, greater than about 75 ml / min, or greater than about 100 ml / min.

[0031] The scale 124 may then include a container for collecting fluid overflow from the 100, for example, from a relief valve downstream of the quick-opening flow control device 122. The container is coupled to the scale 124 so that the weight of the overflowed fluid can be weighed by the scale 124. In one or more embodiments, the container may be removably coupled to the scale 124, for example, to facilitate draining fluid from the container and cleaning the container. The scale 124 may provide the weight readings to the weight recorder 126, and the weight recorder 126 may filter the weight readings received from the scale 124 to remove noise and / or other non-weight-related interference from the readings.The weight recorder 126 may record the received weight readings at a periodic rate of 0.1 Hertz, 0.5 Hertz, 1 Hertz, 2 Hertz, 10 Hertz, or another periodic rate. The weight recorder 126 may store each weight measurement as an entry in a file representing the given weight value and the time associated with the time value. In one or more embodiments, the weight recorder 126 determines a tare weight output by the scale 124 when no fluid is contained in the container coupled to the scale 124 and automatically compensates the weight reading received from the scale 124 based on the tare weight before generating new data records, which are stored in the weight file.

[0032] In one or more embodiments, a computer 128 may receive pressure data from the pressure recorder 120 and weight data from the weight recorder 126. For example, the computer 128 may establish a wireless communication link or a wired communication link with the pressure recorder 120 and download the pressure-time data entries to a data store 130. The computer 128 may simultaneously or at a different time establish a wireless communication link or a wired communication link with the weight recorder 126 and download the weight-time data entries to the data store 130. Alternatively, the pressure and weight data may be transmitted from the pressure recorder 120 and from the weight recorder 126 to the computer 128, essentially when the respective data is acquired.Data storage 130 may be a database, a flat file stored in memory or secondary storage, a directory service such as an LDAP (lightweight directory access protocol) store, or another form of data storage. Computer 128 may process the data received from recording devices 120, 126 in a variety of ways and may process the data associated with various separate data sets acquired during different phases of the rock core test.

[0033] With brief reference to Fig. 2, a system 200 is described. The system 200 is substantially similar to the system 100 described above, but instead of the quick-opening flow control device 122, the system 200 includes a perforation assembly 210. Also with brief reference to Fig. 3, a system 300 is described. The system 300 is substantially similar to the system(s) 100, 200 described above, but instead of the quick-opening flow control device 122 and the perforation assembly 210, respectively, the system 300 includes a test gravel filter assembly 310. In one or more embodiments, the system 100 is suitable for completing a first phase of rock core testing, the system 200 is suitable for completing a perforation phase of the rock core testing, and the system 300 is suitable for completing a gravel filter phase of the rock core testing, as described in more detail below.

[0034] With reference to the Fig. 4A-4C illustrate various configurations of test gravel filter assemblies 400A, 400B, 400C manufactured and designed according to embodiments of the disclosure. The test gravel filter assembly 400A could be configured for use with the system 100 described above with respect to Fig. 1, whereas the test gravel filter assembly 400B and the test gravel filter assembly 400C could be configured for use with the systems 200, 300 described above with respect to the Fig. 2 and 3, respectively. The test gravel filter assemblies 400A, 400B, 400C include many similar or even identical features. Accordingly, like reference numerals may be used to designate similar or even identical features.

[0035] With brief reference to Fig. 4A, the test gravel filter assembly 400A includes a rock core sample 410 coupled to a borehole test structure 490, all positioned within a pressure vessel 499. With brief reference to Fig. 4B, the test gravel filter assembly 400B additionally includes a perforation assembly 495 such as could be used to form perforated regions 498 in the rock core sample 410. With brief reference to Fig. 4C, the test gravel filter assembly 400C additionally includes a test gravel filter assembly 460.

[0036] With reference to Fig. 5 is an enlarged view of the test gravel filter assembly 400A from the dotted field C shown in Fig. 4C. The test gravel filter assembly 400C initially includes the rock core sample 410, which has an axial pore end 413 and a borehole end 418. The rock core sample 410 may include, among other cores, a field core or an analog core and still be within the scope of the present disclosure. The rock core sample 410 according to the disclosure is of the type most likely to be found at the location of interest (e.g., where a customer may wish to drill an oil / gas well). Many materials for the rock core sample 410 are within the scope of the disclosure, and thus, the disclosure should not be limited to any specific material.

[0037] The rock core sample 410 can take on a variety of different sizes and still be within the scope of the disclosure. However, in one embodiment, the rock core sample 410 has a diameter (d1) of at least about 18 cm (e.g., slightly more than 7 inches). In another embodiment, the rock core sample 410 has a diameter (d1) of at least about 20.5 cm (e.g., slightly more than 8 inches), and in yet another embodiment, the rock core sample 410 has a diameter (d1) of at least about 21.5 cm (e.g., slightly more than 8.5 inches). It is believed that for systems with large holes (e.g., larger-shaped charges), the rock core sample 410 benefits from having one of the larger diameters (d1). If the diameter (d1) of the rock core sample 410 is insufficient, the rock core sample 410 may fail during the testing process (especially after undergoing the perforation process and subjected to higher pressures).The rock core sample 410 may additionally have other lengths (l1) and still be within the scope of the disclosure. However, in one embodiment, the rock core sample 410 has a length (l1) of at least about 36 cm (e.g., slightly more than 14 inches). In yet another embodiment, the rock core sample 410 has a length (l1) of at least about 46 cm (e.g., slightly more than 18 inches).

[0038] The rock core sample 410 from Fig. 1 includes a perforated region 420 in an upper portion thereof. The perforated region 420 may, as further discussed below, be either a hole in the rock core sample 410 or, alternatively, a region of disturbed rock consisting of crushed and cracked pieces of the rock core sample 410. The perforated region 420 may also vary in size. However, in one test example, the perforated region 420 has a diameter (d2) of at least about 7.5 cm (e.g., slightly less than about 3 inches). However, in another test example, the perforated region 420 has a diameter (d2) of at least about 10 cm (e.g., slightly less than about 4 inches). In one test example, the perforated region 420 extends a distance (d2) of at least about 6 cm (e.g., slightly less than about 2.5 inches) into the rock core sample 410.However, in another test example, the perforated region 420 extends a distance (d2) of at least about 7.5 cm (e.g., slightly less than about 3 inches) into the rock core sample 410.

[0039] In the perforated area 420 in the test gravel filter assembly 400C of Fig. 5, a proppant 430 is backfilled. The proppant 430 may comprise a typical gravel filter material such as may be used in the oil / gas industry. The proppant 430 is configured to simulate the gravel filter that might be present in an oil / gas well. Those skilled in the art will be aware of the one or more different materials that the proppant 430 may comprise, including 20 / 40, 40 / 70, ceramic beads, etc.

[0040] The test gravel filter assembly 400C further includes a sleeve 440 (e.g., an impermeable sleeve, a tube, etc.) surrounding a longitudinal circumference of the rock core sample 410. The sleeve 440, in one embodiment, has an inner diameter (d3) such that an annular space exists between the inner diameter (d3) of the sleeve 440 and the outer diameter (d1) of the rock core sample 410. In a particular embodiment, the inner diameter (d3) is approximately 1.25 cm larger than the diameter (d1) of the rock core sample 410. Accordingly, the sleeve 440 may have an inner diameter (d3) of approximately 22.75 cm, with the rock core sample 410 having a diameter (d1) of approximately 21.5 cm. However, other embodiments exist in which no easily measurable space exists between the sleeve 440 and the rock core sample 410.

[0041] In the specific embodiment of Fig. 5, a proppant 450 is placed in the annular space between the sleeve 440 and the rock core sample 410. The proppant 450 may be a filler material spaced substantially equidistantly around the rock core sample 410. In at least one embodiment, rods are placed in the annular space so that the same spacing is created and the proppant 450 can be placed therein. The second proppant 450 may be uniform beads, such as ceramic, bauxite, or any other suitable material. In certain embodiments, the proppant 430 and the second proppant 450 comprise the same material, and in other embodiments, the proppant 430 and the second proppant 450 comprise different materials.

[0042] A gravel screen simulation rig 460 is positioned over the downhole end 418 of the rock core sample 410 above the perforated area 420. The gravel screen simulation rig 460 will most likely be fabricated to match the borehole casing, screen, spacers, perforation tunnel, through-hole size, and any other relevant features. Generally speaking, each gravel screen simulation rig 460 may vary from well to well being simulated.

[0043] The laboratory setup for simulating a gravel screen 460 according to the disclosure includes a housing 461 having a first surface 462 and a second opposing surface 463. According to one embodiment of the disclosure, the first and second opposing surfaces 462, 463 define a thickness (t) that simulates a desired thickness of the wellbore gravel screen. In the illustrated embodiment shown, the first surface 462 has a first diameter (d4) and the second opposing surface has a second larger diameter (d5), for example, as defined by the step feature in the housing 461.

[0044] In one or more embodiments, an opening 465 may extend completely through the casing 461 from the first surface 462 to the second surface 463. The opening 465 may have a diameter (d6) that simulates a desired perforation diameter of a wellbore casing. Accordingly, the opening 465 may be tailored to the specific formation it is intended to approach. An additional proppant 470 may be located within the opening 465, e.g., filled therein. Those skilled in the art will know the one or more other materials that the proppant 470 may comprise. For example, the proppant 470 most likely comprises the same material as the proppant 430 and may or may not comprise the same material as the second proppant 450.

[0045] In one or more embodiments, a proppant screen 475 is positioned over the proppant 470 and the opening 465. The proppant screen 475 is coupled, as shown in the illustrated embodiment, proximate the first opposing surface 462 and is configured to hold the proppant 430 and the proppant 470 in place. The proppant screen 475 may be configured to approximate a screen such as may be used in a conventional oil / gas well. The proppant screen 475 may be a removable proppant screen held in place with two or more fasteners 480. For example, in the particular embodiment shown, four screws are used to hold the proppant screen 475 in place.

[0046] A well test structure 490 is positioned above the laboratory facility for simulating a gravel filter 460. In the illustrated embodiment of Fig. 5, the well test structure 490 substantially surrounds the gravel screen simulation laboratory setup 460. Furthermore, in the illustrated embodiment, the well test structure 490 includes a step feature corresponding to the step feature in the gravel screen simulation laboratory setup 460. The well test structure 490, in this embodiment, is configured to approximate a conventional oil / gas well bore. The well test structure 490 is additionally configured to subject the rock core sample 410 to similar downhole pressures and temperatures as may be found in a conventional oil / gas well.

[0047] The Fig. 6 and Fig. 7 illustrate a gravel filter simulation lab setup 600 and a cap 700 manufactured and designed according to the disclosure. In this case, the cap 700 would hold the proppant screen (not shown) over the opening in the gravel filter simulation lab setup 600, thus holding any proppant in a fixed position within the gravel filter simulation lab setup 600.

[0048] A test gravel filter assembly, such as assemblies 400A, 400B, and 400C, can be used to test the feasibility of a gravel filter assembly (e.g., 400C) under downhole conditions. Testing of the gravel filter assembly (e.g., 400B) would begin with obtaining a rock core sample (e.g., a field core or analog core, 410). The rock core sample (e.g., 410) would then be placed in an impermeable sleeve (e.g., 440). The rock core sample (e.g., 410) and the impermeable sleeve (e.g., 440) would be loaded into a container with a perforator (e.g., 495) designed for downhole perforation. The container would then be pressurized to achieve downhole conditions or customer-agreed test conditions. During testing, the container can be heated or left at ambient temperature. Once the appropriate conditions are reached, a load (e.g.A blast (in one embodiment, a shaped charge) is fired into the rock core sample (e.g., 410), forming the perforated region (e.g., 498). The pressure is then released from the container, and the perforator (e.g., 495) is removed therefrom.

[0049] After removing the gravel filter assembly (e.g., 400B) from the container, the proppant (e.g., 430) can be physically placed in the area of lower-density rock matrix created by the perforation event, and / or an open void can be created according to preferred requirements and the open void filled with proppant (e.g., 430). Thereafter, the gravel filter simulation lab device (e.g., 460) can be installed on the rock core sample (e.g., 410), and the opening (e.g., 465) in the gravel filter simulation lab device (e.g., 460) can be filled with proppant (e.g., by top-pouring, 470). A screen (e.g. 475) can then be installed over the opening (e.g. 465) and the well test structure (e.g. 490) can be installed over it.

[0050] When the test gravel filter assembly is substantially complete, the test gravel filter assembly can be returned to the container and flow tests can be conducted. The flow tests can be conducted under high pressures (e.g., greater than 15K PSI) in the presence of one or more different types of fluids. In certain embodiments, the flow tests can be conducted under very high pressures (e.g., greater than 25K PSI) or, in still other embodiments, under extremely high pressures (e.g., greater than 40K PSI). A test gravel filter assembly according to the disclosure can handle any of high, very high, and extremely high pressures while providing useful data and maintaining the test gravel filter assembly intact. In one embodiment, the flow tests are conducted in the presence of, among others, odorless mineral spirits (OMS) or a light kerosene.

[0051] With reference to Fig. 8, an embodiment of a method for performing a rock core flow function test 800 is described. In one or more embodiments, the method 800 may be employed to perform a transient pressure test. The method begins at a start step 805, and at a step 810, one or more properties of a subterranean rock sample from the borehole to be perforated are determined. The properties may include the density of the rock, the permeability of the rock, the type of rock, and other relevant properties. At step 815, based on the properties of the subterranean rock sample, a cut rock is selected that appropriately models the subterranean rock, and the cut rock sample is formed into a rock core sample having a suitable shape for the flow tests.For example, step 815 could involve rotating the rock core sample. It should be understood that the rock core sample can be cut to any length and rotated to any suitable diameter. The depth of the perforation expected to be created by the explosive charges of the perforation gun can be used to determine, at least in part, the length of the rock core sample.

[0052] At step 820, a high-pressure flow test is performed on the rock core sample. This method is described in more detail above. In one or more embodiments, this high-pressure flow test includes maintaining an overcharge or confining pressure of greater than 25,000 PSI on the rock core sample. At step 825, a perforation assembly is coupled to a downhole end of the rock core sample. At step 830, the perforation assembly is activated to perforate the rock core sample. At step 835, a high-pressure flow test is performed on the perforated rock core sample. In one or more embodiments, this high-pressure flow test includes maintaining an overcharge or confining pressure of greater than 25,000 PSI on the rock core sample.The high pressure flow test of the perforated rock core sample may be performed in substantially the same manner as step 820, also discussed above.

[0053] At step 840, a test gravel filter assembly is coupled to the downhole end of the rock core sample. At step 845, another high-pressure flow test is performed on the rock core sample to which the test gravel filter assembly is coupled. In some embodiments, steps 825, 830, and 840 are optional, and the method proceeds directly from step 820 to step 840.

[0054] The method continues with step 850, where a production ratio is determined based on data collected during the high pressure flow test performed on the non-perforated rock core sample, during the optional high pressure flow test performed on the perforated rock core sample, and during the high pressure flow test performed with the test gravel filter assembly.

[0055] With further brief reference to the Fig. 1-3, the processing of step 850 may include the computer 128 downloading data from the pressure recorder 120 and / or the weight recorder 126 and analyzing that data. Alternatively, the data may be transmitted from the pressure recorder 120 and / or the weight recorder 126 when the data is acquired by those recorders 120, 126.

[0056] The computer 128 may further determine flow rates through the rock core sample at various times during the high-pressure flow test of the imperforate rock core sample, during the high-pressure flow test of the perforated rock core sample, and during the high-pressure flow test of the perforated rock core sample in the presence of the laboratory equipment simulating a gravel filter. The flow rates may be determined based on the weight samples downloaded from the weight recorder 126 and based on balancing compaction effects of the fluid flowing within the rock core sample 102. For example, a balancing application executed by the computer 128 may reference a table defining fluid compaction rates at various pressures.A fluid compression ratio may be proportional to the ratio of the volume of a unit mass of the fluid in question at a standard pressure, such as atmospheric pressure, to the volume of the unit mass of the fluid in question at an elevated pressure, such as a pressure of 30,000 psi. Alternatively, a fluid compression ratio may be proportional to the ratio of the volume of a unit mass of the fluid in question at an elevated pressure to the volume of the unit mass of the fluid in question at standard pressure.

[0057] The table may define the compression ratio of the fluid in question at 5000 PSI, 10000 PSI, 15000 PSI, 20000 PSI, 250000 PSI, 30000 PSI, 35000 PSI, 40000 PSI, 45000 PSI, 50000 PSI, 55000 PSI, and 60000 PSI, respectively. In another embodiment, the table may define more or fewer entries. The table may define different pressure indices, for example, unevenly spaced pressure indices. Instead of a table having entries with evenly spaced pressure indices, the table may have entries with evenly spaced compression ratios and corresponding pressure indices associated with each compression ratio. For pressure values between table entries, the applicable compression ratio can be interpolated linearly between the two nearest pressure indices in the table or by another method.

[0058] With brief reference to Fig.9 illustrates a process flow 900 that expands steps 840, 850, and 860 into substeps. The process flow 900 begins with positioning a test gravel filter assembly (e.g., 400A) in a pressure vessel (e.g., 499) at a step 910. Subsequently, at a step 920, a pressure applied to the axial pore end (e.g., 413) of the rock core sample (e.g., 410) is increased to a first pressure, wherein the first pressure is greater than about 15,000 pounds per square inch (PSI). In a step 930, a pressure applied to the downhole end (e.g., 418) of the rock core sample (e.g., 410) is increased to a second pressure greater than approximately 15,000 pounds per square inch (PSI). Steps 920 and 930 may be performed in reverse order.In another embodiment, steps 920 and 930 are performed at the same time, and further, their pressures are kept substantially equal as the pressures increase to the first pressure.

[0059] Subsequently, in a step 940, a pressure differential may be created between the pressures applied to the axial pore end (e.g., 413) of the rock core sample (e.g., 410) and the borehole end (e.g., 418) of the rock core sample (e.g., 410). This pressure differential induces fluid flow between the axial pore end (e.g., 413) and the borehole end (e.g., 418) and through the opening (e.g., 465). For example, the pressure differential may be formed by reducing the pressure exerted on one of the axial pore end (e.g., 413) or the borehole end (e.g., 418) of the rock core sample (e.g., 410) while maintaining the pressure exerted on the other of the borehole end (e.g., 418) or the axial pore end (e.g., 413) of the rock core sample (e.g., 410). In one embodiment, a quick-opening flow control device (e.g.,122) is fluidly coupled to the downhole end (e.g., 418) of the rock core sample (e.g., 410) and the quick-opening flow control device (e.g., 122) is actuated to generate the threshold pressure differential.

[0060] At step 950, an overflow of fluid flowing through the rock core sample (e.g., 410), the opening (e.g., 465), and the removable proppant screen (e.g., 475) is detected after the pressure differential is established, and at step 960, the overflow of fluid is weighed. With this information, at step 970, a first flow volume of fluid through the rock core sample (e.g., 410) is determined based on a weight of the overflow of fluid.

[0061] Referring again to method 800, at step 855, the wellbore perforation and / or gravel filtering process may be adjusted based on the production ratio and / or based on other flow metrics determined based on the high-pressure flow tests. For example, the gravel filtering process may be adjusted to provide better flow characteristics, including changing the thickness of the proppant, changing the type of proppant, etc. Additionally, the shaped charge may be adjusted to more widely disperse explosive energy, the design of the shaped charge liner may be adjusted, and the tool body near the shaped charge may be adjusted.

[0062] Aspects revealed in this writing include: A test gravel filter assembly including a housing having a first surface and a second opposing surface, the first surface and the second opposing surface defining a thickness simulating a desired thickness of a wellbore gravel filter, an opening extending completely through the housing from the first surface to the second opposing surface, the opening having a diameter simulating a desired perforation diameter of a wellbore casing, and a proppant screen coupled proximate the first surface and above the opening. B. Rock core flow test system, the rock core flow test system comprising: a pressure vessel, a test gravel filter assembly positioned within the pressure vessel, the test gravel filter assembly comprising: a) a laboratory facility for simulating a gravel filter, including 1) a housing having a first surface and a second opposing surface, the first surface and the second opposing surface defining a thickness simulating a desired thickness of a wellbore gravel filter, 2) an opening extending completely through the housing from the first surface to the second opposing surface, the opening having a diameter simulating a desired perforation diameter of a wellbore casing, and 3) a proppant screen coupled proximate the first surface and above the opening, b) a wellbore test structure,surrounding the laboratory facility for simulating a gravel filter, c) a rock core sample having an axial pore end and a borehole-facing end, and further wherein the borehole-facing end of the rock core sample is in contact with the second opposing surface, the rock core flow test system further comprising: a first high-pressure accumulator coupled to the pressure vessel and in fluid communication with the axial pore end of the rock core sample, and a pressure sensor coupled to the pressure vessel for measuring pressure changes in one or both of the first high-pressure accumulator or the second high-pressure accumulator. C. A method for conducting a rock core flow function test, the method comprising: positioning a test gravel filter assembly in a pressure vessel, the test gravel filter assembly comprising: a) a laboratory facility for simulating a gravel filter, the laboratory facility for simulating a gravel filter comprising: 1) a housing having a first surface and a second opposing surface, the first surface and the second opposing surface defining a thickness simulating a desired thickness of a wellbore gravel filter, 2) an opening extending completely through the housing from the first surface to the second opposing surface, the opening having a diameter simulating a desired perforation diameter of a wellbore casing, and 3) a removable proppant screen,which is coupled near the first surface and above the opening, b) a borehole test structure surrounding the laboratory facility for simulating a gravel filter, and c) a rock core sample having an axial pore end and a borehole-facing end, and further wherein the borehole-facing end of the rock core sample is in contact with the second opposite surface, the method further comprising: increasing a pressure applied to the axial pore end of the rock core sample to a first pressure, the first pressure being greater than 15,000 pounds per square inch (PSI), increasing a pressure applied to the borehole-facing end of the rock core sample to a second pressure being greater than 15,000 pounds per square inch (PSI), creating a pressure differential between the pressures,applied to the axial pore end of the rock core sample and the borehole end of the rock core sample, wherein the pressure differential induces fluid flow between the axial pore end and the borehole end and through the opening, detecting an overflow of a fluid flowing through the rock core sample and the opening and the removable proppant screen after the pressure differential has been created, weighing the overflow of the fluid, and determining a first flow volume of the fluid through the rock core sample based on a weight of the overflow of the fluid.

[0063] Aspects A, B, and C may include one or more of the following additional elements in any combination: Element 1: wherein the proppant screen is a removable proppant screen. Element 2: wherein two or more fasteners couple the removable proppant screen to the first surface. Element 3: wherein the first surface has a first diameter and the second opposing surface has a second larger diameter. Element 4: wherein the housing includes a step feature defining the first diameter and the second larger diameter. Element 5: wherein the housing, the opening, and the proppant screen form at least a portion of a gravel screen simulation laboratory facility, and further comprising a well test structure surrounding the gravel screen simulation laboratory facility.Element 6: further comprising a rock core sample having an axial pore end and a borehole end, and further wherein the borehole end of the rock core sample is in contact with the second opposing surface. Element 7: wherein the rock core sample has a perforated region exposed to the opening, and further wherein a proppant is filled within the perforated region and the opening and held in place by the proppant screen. Element 8: wherein a sleeve surrounds a longitudinal periphery of the rock core sample. Element 9: wherein an annular space exists between the sleeve and the longitudinal periphery of the rock core sample, and further wherein a second proppant is disposed within the annular space. Element 10: wherein the proppant and the second proppant comprise a like material.Element 11: wherein the rock core sample has a perforated region in the borehole end exposed to the opening, and further wherein a proppant is filled in the perforated region and the opening and held in place by the proppant screen. Element 12: wherein a sleeve surrounds a longitudinal perimeter of the rock sample, thereby forming an annular space between the sleeve and the longitudinal perimeter of the rock core sample, and further wherein a second proppant is disposed within the annular space.Element 13: further comprising a quick-opening flow control device fluidly coupled to the downhole end, wherein the quick-opening flow control device is operable to open when a pressure differential across the quick-opening flow control device exceeds a predefined threshold, and further wherein the pressure sensor is located in the fluid flow between the quick-opening flow control device and the second high-pressure accumulator.Element 14: wherein the rock core sample has a perforated region in the downhole end exposed to the opening, and further comprising backfilling a proppant into the perforated region and the opening prior to positioning the test gravel filter assembly in the pressure vessel, the proppant being held in place by the proppant screen, and further wherein the pressure differential induces fluid flow between the axial pore end and the downhole end and through the proppant in the perforated region and in the opening.Element 15: wherein the increasing pressure exerted on the axial pore end of the rock core sample and the increasing pressure exerted on the downhole end of the rock core sample are maintained substantially equal as the pressures increase to the first pressure, and further wherein creating the pressure differential comprises decreasing the pressure exerted on one of the axial pore end or the downhole end of the rock sample while maintaining the pressure exerted on the other of the downhole end or the axial pore end of the rock core sample. Element 16: wherein a quick-opening flow control device is fluidly coupled to the downhole end of the rock core sample.Element 17: wherein creating the pressure differential includes, while maintaining the pressure applied to the axial pore end of the rock core sample at the first pressure, reducing the pressure applied to the downhole end of the fast-opening flow control device until the fast-opening flow control device is activated, the fast-opening flow control device being activated in response to a threshold pressure differential across the fast-opening flow control device.

[0064] Those skilled in the art to which this application pertains will understand that other and further additions, deletions, substitutions, and modifications may be made to the described embodiments.

Claims

[1] Test gravel packing assembly (460) comprising: a housing (461) having a first surface (462) and a second opposing surface (463), the first surface (462) and the second opposing surface (463) defining a thickness (t) that simulates a desired gravel pack thickness in the borehole; an opening (465) extending completely through the housing (461) from the first surface (462) to the second opposite surface (463), the opening (465) having a single diameter (d6) simulating a desired wellbore casing perforation diameter in the wellbore; and a proppant screen (475) coupled adjacent to the first surface (462) and above the opening (465). [2] The test gravel packing assembly of claim 1, wherein the proppant screen (475) is a removable proppant screen (475) or optionally wherein two or more fasteners (480) couple the removable proppant screen (475) to the first surface (462). [3] The test gravel packing assembly of claim 2, wherein the first surface (462) has a first diameter (d4) and the second opposing surface (463) has a second, larger diameter (d5) or optionally wherein the housing (461) includes a step feature defining the first diameter (d4) and the second, larger diameter (d5). [4] The test gravel pack assembly of claim 1, wherein the housing (461), the opening (465), and the proppant screen (475) form at least a portion of a laboratory facility for simulating a gravel screen (460), and further comprising a well test structure (490) surrounding the laboratory facility for simulating a gravel screen (460). [5] The test gravel packing assembly of claim 4, further including a rock core sample (410) having an axial pore end and a borehole facing end, and further wherein the borehole facing end of the rock core sample (410) is in contact with the second opposing surface (463). [6] The test gravel packing assembly of claim 5, wherein the rock core sample (410) has a perforated region exposed to the opening (465), and further wherein proppant (430) is packed into the perforated region and the opening (465) and held in place by the proppant screen (475). [7] The test gravel packing assembly of claim 6, wherein a sleeve (440) surrounds a longitudinal periphery of the rock core sample (410) or optionally wherein an annular space is provided between the sleeve (440) and the longitudinal periphery of the rock core sample (410), and further wherein a second support means (450) is located within the annular space or optionally wherein the support means (430) and the second support means (450) comprise a same material. [8] Rock core flow test system, comprising: a pressure vessel (499); a test gravel packing assembly (400C) positioned within the pressure vessel (499), the test gravel packing assembly including: a laboratory facility for simulating a gravel filter, including: a housing (461) having a first surface (462) and a second opposing surface (463), the first surface (462) and the second opposing surface (463) defining a thickness (t) that simulates a desired gravel pack thickness in the borehole; an opening (465) extending completely through the housing (461) from the first surface (462) to the second opposite surface (463), the opening (465) having a single diameter (d6) simulating a desired wellbore casing perforation diameter in the wellbore; and a proppant screen (475) coupled adjacent to the first surface (462) and above the opening (465); a borehole test structure (490) surrounding the laboratory facility for simulating a gravel filter; and a rock core sample (410) having an axial pore end and a borehole-facing end, and further wherein the borehole-facing end is in contact with the second opposing surface (463); a first high pressure accumulator (108) coupled to the pressure vessel (499) and in fluid communication with the axial pore end of the rock core sample (410); a second high-pressure accumulator (112) coupled to the pressure vessel (499) and in fluid communication with the borehole end of the rock core sample (410); and a pressure sensor (116) coupled to the pressure vessel (499) for measuring pressure changes at one or both of the first high-pressure accumulator (108) or the second high-pressure accumulator (112). [9] The rock core flow test system of claim 8, wherein the rock core sample (410) has a perforated region in the borehole end exposed to the opening (465), and further wherein proppant (430) is packed into the perforated region and the opening (465) and held in place by the proppant screen (475). [10] The rock core flow test system of claim 9, wherein a sleeve (440) surrounds a longitudinal periphery of the rock core sample (410), thereby forming an annular space between the sleeve (440) and the longitudinal periphery of the rock core sample (410), and further comprising a second support means (450) located within the annular space. [11] The rock core flow test system of claim 8, further including a quick-open flow control device (122) fluidly coupled to the downhole end of the rock core sample (410), wherein the quick-open flow control device (122) is operable to open when a pressure differential across the quick-open flow control device (122) exceeds a predefined threshold, and further wherein the pressure sensor (116) is in fluid flow between the quick-open flow control device (122) and the second high pressure accumulator (112). [12] A method for conducting a rock core flow performance test, comprising: Positioning a test gravel packing assembly within a pressure vessel (499), the test gravel packing assembly comprising: a laboratory facility for simulating a gravel filter, including: a housing (461) having a first surface (462) and a second opposing surface (463), the first surface (462) and the second opposing surface (463) defining a thickness (t) that simulates a desired gravel pack thickness in the borehole; an opening (465) extending completely through the housing (461) from the first surface (462) to the second opposite surface (463), the opening (465) having a single diameter (d6) simulating a desired wellbore casing perforation diameter in the wellbore; and a removable proppant screen (475) coupled adjacent to the first surface (462) and above the opening (465); a borehole test structure (490) surrounding the laboratory facility for simulating a gravel filter; and a rock core sample (410) having an axial pore end and a borehole-facing end, and further wherein the borehole-facing end of the rock core sample (410) is in contact with the second opposing surface (463); Increasing a pressure applied to the axial pore end of the rock core sample (410) to a first pressure, the first pressure being greater than 1000 bar (15,000 pounds per square inch (PSI)); Increasing a pressure applied to the borehole end of the rock core sample (410) to a second pressure greater than 1000 bar (15,000 pounds per square inch (PSI)); Creating a pressure differential between the pressures applied to the axial pore end of the rock core sample (410) and the borehole end of the rock core sample (410), the pressure differential inducing fluid flow between the axial pore end and the borehole end and through the opening (465); detecting an overflow of a fluid flowing through the rock core sample (410), the opening (465) and the removable proppant screen (475) after the pressure differential is created; Weighing the excess of fluid; and Determining a first flow volume of the fluid through the rock core sample (410) based on a weight of the excess fluid. [13] The method of claim 12, wherein the rock core sample (410) has a perforated region in the downhole end exposed to the opening (465), and further including packing a proppant (430) into the perforated region and the opening prior to positioning the test gravel packing assembly within the pressure vessel (499), the proppant (430) being held in place by the proppant screen (475), and further wherein the pressure differential induces fluid flow between the axial pore end and the downhole end and through the proppant (430) in the perforated region and in the opening (465). [14] The method of claim 12, wherein increasing a pressure applied to the axial pore end of the rock core sample (410) and increasing a pressure applied to the borehole-facing end of the rock core sample (410) are kept substantially equal while the pressures increase to the first pressure, and further wherein creating the pressure difference includes reducing the pressure applied to one of the axial pore end or the borehole-facing end of the rock core sample (410) while maintaining the pressure applied to the other of the borehole-facing end or the axial pore end of the rock core sample (410). [15] The method of claim 14, wherein a rapid opening flow control device (122) is fluidly coupled to the downhole end of the rock core sample (410), or optionally wherein creating the pressure differential while maintaining the pressure applied to the axial pore end of the rock core sample (410) at the first pressure includes reducing the pressure applied to the downhole end of the rapid opening flow control device (122) until the rapid opening flow control device (122) is activated, the rapid opening flow control device (122) being activated in response to a threshold pressure differential across the rapid opening flow control device (122).

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