An experiment system and transparent experiment method for replicating fluid displacement in a pore structure of a natural rock mass are provided. The natural pore structure is extracted and a digital porous model corresponding to the natural rock mass is reconstructed with the image processing method. Based on the digital porous model, a three-dimensional pore structure model with a transparent and visible internal structure is printed by a 3D printing device, such that the pore space inside the three-dimensional pore structure model is visible. In this way, the whole fluid flow during the displacement-seepage process within the natural rock mass can be replicated and visually observed from the outside when performing the displacement-seepage experiment. Further, temperature, flow rate, and pressure can be accurately controlled, to replicate various experiment conditions, so as to perform quantitative analysis on distribution features of a seepage field and a fluid speed field.

A method for determining residual fluid saturation of a subsurface formation includes acquiring a sample of the subsurface formation, determining a first residual oil saturation during a water flooding process, determining a second residual oil saturation during a gas flooding process, determining a third residual oil saturation during an enhanced oil recovery (EOR) processes, and determining irreducible water saturation during an oil displacing water process.

Implementations of the disclosure relate to apparatus and methods for supporting and testing respirators during testing operations. In one aspect, the respirators are tested to determine if the respirators meet a testing standard. In one implementation, a test fixture for supporting respirators during testing operations includes a fixture. The fixture includes a base portion, and a first protrusion including one or more first mounting surfaces disposed above the base portion. The fixture includes a second protrusion including one or more second mounting surfaces disposed above the base portion, and a backside surface that opposes the first protrusion and the second protrusion. The fixture includes a cavity disposed between the first protrusion and the second protrusion, and an aperture extending from the cavity and to the backside surface.

A method for establishing mathematical model of relationship between spontaneous imbibition volume and time of porous medium includes sample pretreatment, fully-saturation and centrifugal experiments and NMR T.sub.2 measurement. First, two rock core samples of predetermined size are selected for cleaning and drying. The first rock sample is vacuumed and injected with water to obtain a saturated sample for NMR T.sub.2 measurement. Then, spontaneous imbibition experiment is conducted on another sample, and T.sub.2 measurements are conducted to obtain the water distribution and migration characteristics during the imbibition process. Next, the calculation of the imbibition permeability, average capillary pressure and surface relaxivity are conducted based on the NMR data obtained from two samples. Finally, substitute these parameters into the Handy relationship to obtain a new NMR-based mathematical spontaneous imbibition model.

Disclosed is a seepage and internal erosion test apparatus for geotechnical centrifuges. The apparatus includes a mounting base, a four-motorized-jack synchronized lifting table fixed onto the mounting base, a downstream water sink, a plurality of permeameters, a centrifugal pump, and an upstream water sink fixedly mounted on the four-motorized-jack synchronized lifting table; the downstream water sink, the plurality of permeameters, the centrifugal pump, and the upstream water sink are connected by means of pipes; electric ball valves are separately disposed on each branch on which the permeameter is mounted; a temperature control module and flow meters are disposed of in the pipe for connecting the upstream outlet to the permeameter water inlet.

The present disclosure provides a supergravity simulation system for in-situ stress field and seepage field for deep earth engineering, comprising: a triaxial pressure chamber for placing a model and providing in-situ axial pressure, confining pressure and seepage field of deep earth structure; a simulation control device for providing pressure liquid and pore water to the triaxial pressure chamber to generate the aforementioned axial pressure, confining pressure and seepage field, and controlling the values of the axial pressure, confining pressure and seepage field; a signal acquisition device for monitoring the deformation and seepage process of the model during the test. The invention improves the similarity, reliability, and accuracy of the simulation test, and it can output pressure with an accuracy of 1% or constitute the pore water pressure difference with an accuracy of 1% to the triaxial pressure chamber through the command of the control unit.

A system for testing properties of a sample, the system including a test cell. The test cell includes a cell casing having a first end piece, a second end piece, and at least one wall extending between the first end piece and the second end piece. The cell casing defines a pressure boundary enclosing an interior region of the cell. The test cell further includes a sample chamber, a first reservoir, and a second reservoir disposed within the pressure boundary. The sample chamber defines an interior region. The first reservoir fluidly connects to the interior region of the sample chamber. The second reservoir fluidly connects to the interior region of the sample chamber. The test cell also has a piston assembly having a piston fluid chamber and a piston with a stem extending into the piston fluid chamber. The piston partially defines the sample chamber.

A method for determining properties of different cation exchange sites in a rock core sample may include providing a rock core sample that is in either a preserved state or a non-preserved state, wherein a preserved form of the rock core sample includes a plurality of indigenous exchangeable cations adsorbed onto the cation exchange sites, a plurality of cation exchange sites occupied by a crude oil, and one or more fluids occupying pore spaces in the rock core sample; subjecting the rock core sample to a plurality of coreflooding steps, the plurality of coreflooding step displacing the plurality of indigenous exchangeable cations and the one or more fluids in at least two separate coreflooding steps to render the rock core sample clean of indigenous exchangeable cations; and determining an amount of indigenous exchangeable cations adsorbed onto the cation exchange sites.

A method may include determining an energy factor based on scratch test data and ultrasonic wave data regarding a geological region of interest. The method may further include determining an amount of inelastic energy regarding the geological region of interest using triaxial compression data and rock property data. The method may further include determining a tensile strength regarding the geological region of interest using Brazilian test data. The method may further include generating a geomechanical model regarding the geological region of interest using the energy factor and the amount of inelastic energy. The geomechanical model may include various brittleness values for the geological region of interest. The method may further include determining an injection fluid pressure to induce a hydraulic fracture at a predetermined location in the geological region of interest using the geomechanical model, the tensile strength, and fracture plane roughness data.

A visualization system and method for a multiphase fluids displacement seepage experiment with large viscosity difference in a complex pore structure. The visualization system includes: an injection pump assembly, a visualized complex pore model, a vacuum pressure pump and an image acquisition device; the system and method are printed by a 3D printing device to form the visualized complex pore model with at least two permeability, and displacement fluid mediums of different viscosities are injected into the visualized complex pore model through different injection pumps during an experiment, so that not only is the penetration of the same viscosity in the complex pore structure with different permeability observed, but also the displacement and plugging effect of different viscosities successively entering the complex pore structure with different permeability is realized.