A microfluidic displacement evaluation device under high temperature and high pressure

Abstract

This invention relates to a high-temperature, high-pressure microfluidic displacement evaluation device in the field of microscopic displacement monitoring technology. It includes a base with corresponding left and right columns. A liftable vessel body is located at the center of the base, with an open top. Rotating supports are mounted on the left and right columns, and a vessel body cover is mounted on the rotating supports. The circumference of the vessel body cover mates with the open top of the vessel body. An objective lens support is located at the bottom of the vessel body cover corresponding to the inner cavity of the vessel body, and an objective lens is mounted on the objective lens support. A high-pressure viewing window is located at the center of the vessel body cover above the objective lens. An observation hole is located at the center of the rotating support corresponding to the high-pressure viewing window. A camera is mounted on the vessel body cover above the high-pressure viewing window. A laterally adjustable displacement platform assembly is located on the objective lens support, and a clamping assembly for mounting microfluidic chips is fixed on the displacement platform assembly. The vessel body cover also has several pipeline interfaces and pressure loading pipes communicating with the inside of the vessel.

Description

Technical Field

[0001] This invention relates to the field of microscopic displacement monitoring technology, specifically to a device for observing and evaluating the seepage patterns, such as multiphase fluid displacement, fluid distribution, and flow path analysis, in a microfluidic chip under high temperature and high pressure conditions. Background Technology

[0002] Microfluidics technology has been applied in various fields, including disease diagnosis, drug screening, cell analysis, materials chemistry, environmental monitoring, food safety, and aerospace, and has achieved fruitful results.

[0003] In the field of oil and gas development, microfluidic chips ("artificial cores") combined with high-resolution imaging technology were used in the early stages to study the distribution patterns of residual oil under normal temperature and pressure, solving the problem of not being able to conduct microscopic observations under high temperature and high pressure environments in formations.

[0004] With technological advancements, stereomicroscopy has matured, becoming increasingly suitable for penetrating the thick viewing windows of high-temperature, high-pressure reactors due to its long working distance and large depth of field. Technicians have begun applying stereomicroscopy to the observation of high-temperature, high-pressure microfluidic chips; however, its resolution is limited, typically at the micrometer level (>10 μm), failing to clearly distinguish key interfacial phenomena at the submicrometer to hundreds of nanometer scale (such as oil film distribution, fluid retention within nanopore throats, and microemulsion structural evolution). These details have a decisive impact on microfluidic displacement efficiency.

[0005] Currently, most microfluidic displacement devices rely on manual installation of high-temperature, high-pressure, and visually controlled reactors. Especially under high-temperature and high-pressure conditions, the installation, measurement, and inspection of critical sealing components in the thick viewing window are cumbersome. Adjustments to the observation position during experiments also largely depend on manual adjustments, which can easily disrupt experimental conditions and affect computer image acquisition and measurement, hindering high-resolution image stitching and data processing. Conventional micro-displacement experimental devices only support horizontal installation and experimentation of microfluidic chips under normal pressure or high-temperature, high-pressure conditions, failing to simulate the impact of formation dip angle on the displacing fluid in real-world scenarios. Therefore, there is an urgent need for a highly automated experimental device capable of achieving high-resolution observation of microfluidic chips at the microscale (hundreds of nanometers) under high-temperature, high-pressure formation conditions. Summary of the Invention

[0006] The purpose of this invention is to solve the problems of difficulty in simulating formations from multiple angles and directions, low observation resolution, complex switching operations, and low automation in the existing technology when using a high-temperature and high-pressure visual autoclave for microfluidic displacement simulation. The invention provides a dynamic evaluation device for microfluidic displacement effect at the microscopic level that can simulate high-temperature and high-pressure conditions and perform high-resolution observation of microfluidic chips.

[0007] The objective of this invention is achieved as follows: a microfluidic displacement evaluation device under high temperature and high pressure microscopy, comprising a base, on which are provided left and right corresponding columns. The device is characterized by having a liftable vessel body at the center of the base, with an open top. Rotating supports are provided on the left and right columns, and a vessel body cover is mounted on the rotating supports. The circumference of the vessel body cover mates with the open top of the vessel body. An objective lens support is provided at the bottom of the vessel body cover corresponding to the inner cavity of the vessel body, and an objective lens is mounted on the objective lens support. A high-pressure viewing window is provided at the center of the vessel body cover above the objective lens. An observation hole is provided at the center of the rotating supports corresponding to the high-pressure viewing window. A camera is mounted on the vessel body cover above the high-pressure viewing window. A laterally adjustable displacement platform assembly is provided on the objective lens support, and a clamping assembly for mounting microfluidic chips is fixed on the displacement platform assembly. The vessel body cover also has several pipeline interfaces and pressure loading pipes communicating with the interior of the vessel.

[0008] To facilitate the sealing of the vessel body with the lid, the lower end of the lid is fitted into the inner circumference of the vessel body's opening, and a sealing ring is provided around the circumference of the fitting. The upper side of the lid has a radially protruding upper shoulder, and the upper end of the vessel body has a radially protruding lower shoulder that mates with the upper shoulder. A rotating bracket is rotatably connected to a counter-opening clamp on its lower side. The clamp's engagement part engages with the upper and lower shoulders after fitting, and the clamps are locked in place by bolts. When the vessel body rises to mate with the lid, the mating surfaces of the upper and lower shoulders fit perfectly, creating a circumferential seal. The clamps are then closed to secure the upper and lower shoulders, and the clamps are tightened with bolts, thus achieving the locking and connection between the vessel body and the lid.

[0009] To facilitate the rotational installation of the rotating bracket on the left and right columns, a left bearing seat is provided on the left column, and a left support shaft is provided on the side of the rotating bracket corresponding to the left bearing seat; a speed reducer is provided on the right column, the speed reducer is driven by a motor, a right support shaft is provided on the right side of the rotating bracket, the left support shaft and the right support shaft are coaxially arranged, and the right support shaft is rotatably connected to the output end of the speed reducer.

[0010] To facilitate the lifting and lowering of the vessel body, the base has a central hole for easy lifting and lowering of the vessel body. A lifting push rod is provided below the central hole, and an electromagnet is provided at the upper end of the lifting push rod. An armature is provided at the lower part of the vessel body.

[0011] To facilitate temperature control and internal observation within the vessel, a heating layer and an insulation layer are provided on the outer periphery of the vessel, and an adjustable light source is provided on the inner side of the bottom of the vessel.

[0012] To facilitate the installation of the lifting push rod, a push rod bracket is provided on the bottom side of the base, and the lifting push rod is fixed on the push rod bracket.

[0013] To facilitate the fixed installation of the objective lens, the objective lens holder includes a vertical connecting part and a horizontal connecting part with a right-angle structure. The upper end of the vertical connecting part is fixed to the bottom side of the upper cover of the vessel body. The horizontally extended end of the horizontal connecting part is provided with an objective lens connecting seat for replacing or installing the objective lens. The lower side of the right-angle connecting end of the vertical connecting part and the horizontal connecting part is provided with a downward protruding boss, which is used to connect the displacement platform assembly.

[0014] To facilitate the fixation and position adjustment of the microfluidic chip, the displacement platform assembly includes an X-axis displacement platform and a YZ-axis displacement platform; the YZ-axis displacement platform is connected to the X-axis displacement platform via a right-angle connector, the clamp assembly is connected to the YZ-axis displacement platform, the X-axis displacement platform is driven by an X-axis lead screw motor, and the YZ-axis displacement platform is driven by a Y-axis lead screw motor and a Z-axis lead screw motor, respectively.

[0015] Furthermore, the clamping assembly includes a chip platform, and the chip platform has grippers on both sides for clamping the microfluidic chip.

[0016] The beneficial effects of the high-temperature and high-pressure microfluidic displacement evaluation device of the present invention are as follows: The microfluidic chip for the displacement experiment and the objective lens for microscopic monitoring are both installed inside the reactor, facilitating observation under high-temperature and high-pressure experimental conditions. Through the high-pressure viewing window, an external camera can capture the dynamic image of the microfluidic chip inside the reactor within the focal plane of the objective lens in real time. Combining the external camera with the internal objective lens enables high-resolution monitoring and observation. The objective lens and the clamp assembly for fixing the microfluidic chip are fixed to the lower side of the reactor body cover and mounted as a whole on a rotating bracket. After the reactor body cover is docked and secured to the reactor body, the rotating bracket, driven by a reducer, can rotate the entire reactor body and its internal structure to the required angle, enabling multi-angle and multi-directional experimental observation. Various pipelines inside the reactor achieve sealed connections between the inside and outside of the reactor through pipeline interfaces. After a single connection, when the internal microfluidic chip needs to be replaced, there is no need to disassemble, reassemble, and adjust other pipelines on the reactor body cover again, simplifying the experimental disassembly and assembly process and significantly improving the efficiency of continuous experiments. Attached Figure Description

[0017] Figure 1 This is a perspective view of the microfluidic displacement evaluation device under high temperature and high pressure microscopic conditions of the present invention.

[0018] Figure 2 This is a front view of the microfluidic displacement evaluation device under high temperature and high pressure microscopic conditions according to the present invention.

[0019] Figure 3 This is a schematic diagram of the structure of the lower side of the upper cover of the vessel.

[0020] Figure 4 This is a schematic diagram showing the connection between the vessel body and the vessel cover.

[0021] In the diagram, 1. Camera; 2. Rotating bracket; 201. Left bearing housing; 202. Reducer; 203. Motor; 204. Right bearing housing; 205. Left support shaft; 206. Right support shaft; 3. Upper cover of the vessel; 301. High-pressure viewing window; 302. Upper shoulder; 4. Clamp; 5. Objective lens; 6. Left column; 7. Vessel body; 701. Lower shoulder; 702. Heating layer; 703. Insulation layer; 8. Base; 9. Lifting push rod; 10. Right column; 11. Fixture assembly; 1101. Chip platform; 1102. Gripper; 12. Displacement platform assembly; 1201. X-axis displacement platform; 1201A. X-axis lead screw motor; 1202. YZ-axis displacement platform; 1202A. Y-axis lead screw motor; 1202B. Z-axis lead screw motor; 1203. Right angle connector; 13. Objective lens holder; 1301. Objective lens connector; 14. Electromagnet; 15. Armature; 16. Push rod holder; 17. Microfluidic chip. Detailed Implementation

[0022] The following detailed description of the high-temperature, high-pressure microfluidic displacement evaluation device of the present invention, with reference to the accompanying drawings, is provided in detail.

[0023] like Figures 1-4As shown, the high-temperature and high-pressure microfluidic displacement evaluation device of the present invention includes a base 8. The base 8 has legs at its lower part to support it at a certain height, facilitating experimental operation and the installation and protection of auxiliary equipment at the bottom of the base. The base 8 has a left column 6 and a right column 10 corresponding to each other. A liftable vessel body 7 is located at the center of the base 8. The top of the vessel body 7 has an opening. A rotating bracket 2 is mounted on the left column 6 and the right column 10. A downward-facing vessel body cover 3 is mounted on the rotating bracket 2. When the vessel body cover 3 is aligned with the vessel body 7, they are coaxial vertically. After the circumference of 3 is connected to the open end of the vessel 7, it is fitted with a lid. The bottom of the vessel body cover 3 corresponding to the inner cavity of the vessel body 7 is provided with an objective lens support 13. An objective lens 5 is installed on the objective lens support 13. A high-pressure viewing window 301 is provided at the center of the vessel body cover 3 above the objective lens 5. An observation hole is provided at the center of the rotating bracket 2 corresponding to the high-pressure viewing window 301. A camera 1 is installed on the vessel body cover 3 above the high-pressure viewing window. A translational platform assembly 12 that can be moved and adjusted is provided on the side of the objective lens support 13. A clamping assembly 11 for clamping the microfluidic chip 17 is fixed on the translational platform assembly 12. The upper cover 3 of the vessel body is also equipped with several pipeline interfaces that connect to the interior of the vessel, for internal and external connections of various electrical circuits and monitoring device circuits inside the vessel. Specifically, the pipeline interfaces are connected using a signal transmission device structure as disclosed in the applicant's earlier patent application, publication number CN112881178A. The upper cover 3 of the vessel body is also equipped with a pressure loading pipe for connecting to a high-pressure gas path. In general experiments, this connects to a high-pressure nitrogen pipeline to pressurize the interior of the vessel, meeting the requirements of high-pressure experiments. Furthermore, the high-pressure viewing window structure of the upper cover 3 of the vessel body can adopt the high-temperature and high-pressure glass viewing window structure described in the applicant's earlier patent application, publication number CN217763081U.

[0024] In this invention, the sealing connection between the upper cover 3 and the vessel body 7 is as follows: the lower end of the upper cover 3 is sealed and fitted around the inner circumference of the open opening of the vessel body 7, and a sealing ring is provided around the fitted circumference. The upper side of the upper cover 3 has a radially protruding upper shoulder 302, and the upper end of the vessel body 7 has a radially protruding lower shoulder 701 that mates with the upper shoulder 302. A rotating bracket 2 is rotatably connected to a counter-opening clamp 4 on its lower side. The clamping part of the clamp 4 engages with the connected upper shoulder 302 and lower shoulder 701 for secure fastening. Figure 4As shown, after the clamp 4 is engaged, it is locked with bolts to secure the vessel body and the vessel cover as a whole. During the above docking, when the vessel body 7 rises to dock with the vessel cover 3, the docking end faces of the upper shoulder 302 and the lower shoulder 701 fit together perfectly. The circumference of the sealing sleeve is sealed and fitted under the sealing action of the sealing ring. Then the clamp 4 is closed to secure the upper shoulder 302 and the lower shoulder 701. The clamp is then tightened with bolts to lock the vessel body 7 and the vessel cover 3. In this way, the entire vessel body and its internal components can rotate with the rotating bracket 2 to meet the experimental requirements of multi-angle observation of the microfluidic chip 17 inside the vessel.

[0025] To facilitate the rotational installation of the rotating support 2 on the left column 6 and the right column 10, a left bearing seat 201 is provided on the left column 6, and a left support shaft 205 is provided on the side of the rotating support 2 corresponding to the left bearing seat 201. A reducer 202 is provided on the right column 10, and the reducer 202 is driven by a motor 203. A right support shaft 206 is provided on the right side of the rotating support 2, and the left support shaft 205 and the right support shaft 206 are coaxially arranged. The right support shaft 206 is rotatably connected to the output end of the reducer 202. By driving the output end of the reducer 202 to rotate in both directions by the motor 203, the rotating support 2 can rotate in both directions, thereby driving the rotation of the entire vessel. In this invention, to precisely control the rotation angle of the rotating support 2, the motor 203 is a servo motor, and an electronic level is installed on the rotating support 2. When the motor 203 adjusts the angle of the rotating support 2, the electronic level feeds back the angle signal to the motor's control system, realizing the control and adjustment of the angle of the rotating support 2.

[0026] To facilitate the support and lifting of the vessel body 7, the base 8 has a central hole for easy lifting and lowering of the vessel body 7. A lifting push rod 9 is located below the central hole, with an electromagnet 14 at its upper end and an armature 15 at the lower part of the vessel body 7. The vessel body is securely mounted on the upper end of the lifting push rod 9 through the attraction between the electromagnet 14 and the armature 15. To further secure the lifting push rod 9, a push rod bracket 16 is located on the bottom side of the base 8, and the lifting push rod 9 is fixed to the push rod bracket 16. The lifting push rod of this invention is a push rod structure that can be driven by pneumatic or hydraulic pressure.

[0027] In addition, to facilitate temperature control inside the vessel and meet the needs of experiments at different temperatures, a heating layer 702 and a heat preservation layer 703 are provided on the outer periphery of the vessel body 7. To facilitate clear observation of the conditions inside the vessel, an adjustable light source is provided on the inner side of the bottom of the vessel body 7 for easy video recording of experimental observation.

[0028] To facilitate the fixed installation of the objective lens 5, the objective lens holder 13 includes a vertical connecting part and a horizontal connecting part with a right-angle structure. The upper end of the vertical connecting part is fixed to the bottom side of the upper cover 3 of the vessel body. The horizontally extended end of the horizontal connecting part is provided with an objective lens connecting seat 1301 for replacing or installing the objective lens 5. The lower side of the right-angle connecting end of the vertical connecting part and the horizontal connecting part is provided with a downward protruding boss, which is used to connect the displacement platform assembly 12.

[0029] To facilitate the fixing and position adjustment of the microfluidic chip 17, the displacement platform assembly 12 includes an X-axis displacement platform 1201 and a YZ-axis displacement platform 1202. The YZ-axis displacement platform 1202 is connected to the X-axis displacement platform 1201 via a right-angle connector 1203. The clamping assembly 11 is connected to the YZ-axis displacement platform 1202. The X-axis displacement platform 1201 is driven by an X-axis lead screw motor 1201A, and the YZ-axis displacement platform 1202 is driven by a Y-axis lead screw motor 1202A and a Z-axis lead screw motor 1202B, respectively. The clamping assembly 11 includes a chip platform 1101 for laying the microfluidic chip 17 flat, and grippers 1102 on both sides of the chip platform 1102 for clamping the microfluidic chip 17.

[0030] The high-temperature and high-pressure microfluidic displacement evaluation device of the present invention allows for the selection of different magnification objectives 5 inside the vessel to meet observation requirements. By combining the external camera 1 with the internal objective 5, high-resolution monitoring can be achieved. During the experiment, the microfluidic chip is fixed on the chip platform 1101 of the clamp assembly 11. After connecting the internal and external pipelines, the lifting push rod 9 is activated to raise the vessel body 7 and align it with the vessel cover 3. The clamp 4 is then engaged and tightened with bolts. The vessel is then heated and pressurized according to the experimental temperature and pressure requirements. Once the required temperature and pressure are reached, the imaging program is initiated to capture multiple images. During the imaging process, the X, Y, and Z axes are adjusted using the displacement platform assembly to ensure clear imaging of the objective lens. Multiple images are then captured consecutively, each containing a scale. Finally, the images are stitched together using the scale integrated into the microfluidic chip in the stitching software. Therefore, when conducting experiments on different microfluidic chips using the high-temperature and high-pressure microfluidic displacement evaluation device of the present invention, it is only necessary to unlock the clamps, raise and lower the vessel body, replace the microfluidic chip, close the vessel body, and lock it before conducting the experiment. There is no need to repeat other pipeline connections, which simplifies the experimental process and improves the efficiency of connecting experiments.

Claims

1. A high-temperature and high-pressure microcosmic microfluidic displacement evaluation device, comprising a base (8), the base (8) being provided with a left stand (6) and a right stand (10) corresponding to the left and right, characterized in that, The base (8) is centrally provided with a liftable kettle body (7), the kettle body (7) has an open top, the left stand column (6) and the right stand column (10) are provided with a rotating support (2), the rotating support (2) is provided with a kettle body upper cover (3), the circumference of the kettle body upper cover (3) is matched and covered with the opening of the kettle body, the kettle body upper cover (3) is provided with an objective lens support (13) corresponding to the bottom of the inner cavity of the kettle body, the objective lens support (13) is installed with an objective lens (5), the high-pressure window (301) is provided at the center of the upper cover (3) corresponding to the objective lens (5), the high-pressure window (301) is provided with an observation hole corresponding to the center of the rotating support (2), and the camera (1) is installed on the upper cover (3) on the upper side of the high-pressure window (301); the objective lens support (13) is laterally provided with a translatable displacement platform assembly (12), the displacement platform assembly (12) is fixed with a clamp assembly (11) for clamping a microfluidic chip (17); the kettle body upper cover (3) is further provided with a plurality of pipeline interfaces and pressure loading connecting pipes in communication with the kettle; the objective lens support (13) comprises a vertical connecting part and a horizontal connecting part in a right angle structure, the upper end of the vertical connecting part is fixed with the bottom side of the kettle body upper cover (3), the horizontal extending end of the horizontal connecting part is provided with an objective lens connecting seat (1301) for replacing and installing the objective lens (5), the lower side of the right angle connecting end of the vertical connecting part and the horizontal connecting part is provided with a downward protruding boss, and the boss is used for connecting the displacement platform assembly (12); the displacement platform assembly (12) comprises an X-axis displacement platform (1201) and a YZ-axis displacement platform (1202); the YZ-axis displacement platform (1202) is connected with the X-axis displacement platform (1201) through a right angle connecting seat (1203), the clamp assembly (11) is connected with the YZ-axis displacement platform (1202), the X-axis displacement platform (1201) is driven by an X-axis lead screw motor (1202A), and the YZ-axis displacement platform (1202) is respectively driven by a Y-axis lead screw motor (1201A) and a Z-axis lead screw motor (1202B).

2. The high temperature and high pressure microcosmic microfluidic displacement evaluation device according to claim 1, characterized in that, The lower end of the kettle body upper cover (3) is sealingly sleeved with the inner circumference of the opening of the kettle body, a sealing ring is arranged on the sleeving circumference, the upper side of the kettle body upper cover (3) is provided with a radially protruding upper shoulder (302), the upper end of the kettle body (7) is provided with a radially protruding lower shoulder (701) in butt joint with the upper shoulder (302), the lower side of the rotating support (2) is rotationally connected with a clamping hoop (4) which is oppositely opened and closed, the clamping part of the clamping hoop (4) is clamped and fixed with the upper shoulder (302) and the lower shoulder (701) after butt joint, and the clamping hoop (4) is locked by bolts after closing.

3. The high temperature and high pressure microcosmic displacement evaluation device according to claim 1, wherein, The left upright column (6) is provided with a left bearing seat (201), and the rotary support (2) is provided with a left supporting shaft (205) on the side corresponding to the left bearing seat (201); the right upright column (10) is provided with a speed reducer (202), the speed reducer (202) is driven by a motor (203), the right side of the rotary support (2) is provided with a right supporting shaft (206), the left supporting shaft (205) and the right supporting shaft (206) are coaxially arranged, and the right supporting shaft (206) is rotationally connected with the output end of the speed reducer (202).

4. The high temperature and high pressure microcosmic microfluidic displacement evaluation device according to claim 1, characterized in that, The center of the base (8) is provided with a center hole for facilitating the lifting of the kettle body 7, the lower side of the center hole is provided with a lifting push rod (9) driven by hydraulic pressure or air pressure, the upper end of the lifting push rod (9) is provided with an electromagnet (14), and the lower part of the kettle body (7) is provided with an armature (15).

5. The high temperature and high pressure microcosmic displacement evaluation device according to claim 4, wherein, The outer periphery of the kettle body (7) is provided with a heating layer (702) and a heat preservation layer (703), and the inner side of the bottom of the kettle body (7) is provided with an adjustable light source.

6. The high temperature and high pressure microcosmic displacement evaluation device of claim 4, wherein, The bottom side of the base (8) is provided with a push rod support (16), and the lifting push rod (9) is fixed on the push rod support (16).

7. The high temperature and high pressure micro-displacement evaluation device according to claim 1, wherein, The clamp assembly (11) comprises a chip platform (1101), and the chip platform (1101) is provided with clamping jaws (1102) on both sides for clamping a microfluidic chip (17).

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