Reaction kettle device and experimental method for non-sintered quartz glass microfluidic chip

Abstract

The application discloses a reaction kettle device for non-sintered quartz glass micro-fluidic chips, which comprises a reaction kettle bottom plate, a cover plate, upper and lower recessed groove water injection channels and a bolt structure. The application also discloses a corresponding experimental method. Through water pressure of the upper and lower water injection cavities, the chip is isobarically attached, replacing the traditional sintering process, and solving the problems that the chip cannot be disassembled and reused after sintering. Liquid pressure attachment avoids stress concentration of rigid clamps, is suitable for brittle materials such as quartz glass, and reduces the risk of breakage. After the experiment, the chip can be disassembled for thorough cleaning, improving the reusability, reducing material consumption and experimental cost. The device adopts high-pressure and corrosion-resistant materials, the injection ports are accurately aligned, the bolts are uniformly distributed to ensure reliable sealing, and is suitable for high-temperature and high-pressure reaction experiments in the field of petroleum engineering.

Description

Technical Field

[0001] This invention relates to the field of microfluidic chip technology, and more particularly to a reaction vessel device for non-sintered quartz glass microfluidic chips used in the field of petroleum engineering. Background Technology

[0002] I. Technical Scenarios Microfluidic chip technology serves as a core platform for simulating formation fluid reactions in the petroleum engineering field. Its quartz glass material, due to its high temperature resistance (>1000℃), chemical inertness (resistance to strong acids and alkalis), and optical transparency (facilitating real-time observation of microscopic flow fields), is widely used in high-temperature and high-pressure reaction experiments such as CO2 displacement and shale gas extraction. The encapsulation technology of traditional quartz glass (a brittle material) microfluidic chips is crucial for achieving high-pressure sealing (simulating formation pressures up to 30MPa), directly determining the accuracy of experimental data and the chip's lifespan.

[0003] In visualization displacement experiments of tight oil reservoirs, shale oil reservoirs, and complex fracture systems, microfluidic chips are used to replicate the rock pore network at a 1:1 scale, enabling real-time observation of the seepage mechanisms of crude oil, water, and gas in porous media under a microscope. To simulate formation conditions, the chip must be able to withstand injection pressures of at least 10 MPa, and the width of its internal channels is often only tens of micrometers. Therefore, the experimental platform places extremely high demands on the chip's high-pressure sealing, structural integrity, and visualization clarity.

[0004] The current industry practice is: Quartz glass is selected as the chip substrate, taking advantage of its high light transmittance, high Young's modulus, and chemical corrosion resistance; The cover plate and base plate are permanently bonded together using a sintering process to form a non-removable whole. After sintering, the overall strength of the chip is significantly improved, allowing it to operate under high voltage for extended periods without cracking. An external hydraulic or pneumatic confinement system is used to provide additional lateral restraint for the chip, further reducing the risk of explosion.

[0005] The aforementioned structure has supported numerous high-pressure visualization experiments over the past decade, providing valuable microscopic seepage data for unconventional oil and gas development and laying the technological foundation.

[0006] II. The shortcomings of existing technologies and their direct technical and historical reasons 1. The chip cannot be disassembled after sintering. Once the channel is contaminated by crude oil, emulsion or solid particles, the entire chip will be scrapped.

[0007] Direct technical reason: Sintering relies on the diffusion bonding of quartz glass molecules at high temperatures. This process is irreversible, causing the chip to become a single rigid body that cannot be restarted for cleaning.

[0008] Historical reasons for development: Early microfluidic chips originated from MEMS silicon wafer bonding technology, while quartz glass chips directly followed the "high-temperature permanent bonding" route; subsequently, the demand for high voltage emerged, and the industry continued to increase the sintering temperature and time on this path, rather than questioning "permanent bonding" itself.

[0009] 2. When mechanical fixtures are used to replace sintering, brittle quartz glass is easily broken and the seal is unstable.

[0010] The technical reason is that traditional clamps transmit concentrated loads through metal pressure plates and elastic gaskets. Although quartz glass has a high Young's modulus, it has extremely low fracture toughness. Local stress concentration can generate microcracks. Under high pressure fluctuations, the difference in clamp rebound further amplifies the uneven stress.

[0011] Mechanical clamping originated from early experience in low-voltage PDMS chip packaging. This experience was directly transferred to the high-strength quartz glass scenario, ignoring the essential differences in material properties.

[0012] 3. The confining pressure loading system is complex and its operation is lengthy.

[0013] Direct technical reasons: The external hydraulic / pneumatic system requires a high-pressure pump, pressure stabilizing tank, multi-channel valve group and safety interlock. Leakage in any part will lead to experimental failure; chip replacement requires repeated pressure increase and decrease, and the preparation time for a single operation is >2 hours.

[0014] Historical reasons for development: High-pressure experimental technology initially served core displacement, and large core holders naturally required confining pressure; after the size of microfluidic chips was reduced, the experimental platform directly adopted the design thinking of "large equipment" and was not redesigned for microscale requirements.

[0015] III. Necessity of Improvement Because existing technologies have long been constrained by two path dependencies: "irreversible sintering" and "fragile mechanical clamping," the industry urgently needs a new microfluidic chip packaging solution that can achieve high-pressure sealing without sintering, can be quickly disassembled and cleaned after testing, and can operate at room temperature and pressure. Summary of the Invention

[0016] The purpose of this invention is to provide a reaction vessel device for non-sintered quartz glass microfluidic chips, which solves the problems of non-removability, rigid fixtures easily damaging brittle materials, and the inability to reuse chips caused by the sintering process in traditional microfluidic chip reaction vessels.

[0017] To achieve the above objectives, the reaction vessel device for non-sintered quartz glass microfluidic chips of the present invention includes: The bottom plate of the reactor has a microfluidic chip groove in the center to accommodate the microfluidic chip and form a lower water injection chamber; The lower groove water injection channel is located at the bottom of the groove in the bottom plate of the reactor and is used to inject water into the lower water injection chamber through the groove in the bottom plate of the reactor; the groove in the bottom plate of the reactor communicates with the lower water injection chamber; The reactor cover has an upper groove on the inner side corresponding to the chip position, forming an upper water injection cavity; The upper groove water injection channel is located at the top of the top plate groove and is used to inject water into the upper water injection cavity; the top plate groove communicates with the upper water injection cavity; Bolt structure, used to fasten the reactor cover plate and the reactor bottom plate.

[0018] The size of the groove of the microfluidic chip is matched with the microfluidic chip, and a chip injection port is provided on the bottom plate of the reactor, which corresponds to the fluid inlet channel of the microfluidic chip.

[0019] The upper groove water injection channel and the lower groove water injection channel are symmetrically arranged, and the water injection pressure can be adjusted independently.

[0020] The bolt structure is evenly distributed along the edge of the reactor, with a quantity of no less than 4 bolts.

[0021] The bottom plate and cover plate of the reactor are made of high-pressure resistant and corrosion-resistant materials.

[0022] This invention also provides a corresponding experimental method, which utilizes the above-described reaction vessel device for non-sintered quartz glass microfluidic chips and follows these steps: S1. Chip installation stage; The non-sintered quartz glass microfluidic chip is placed in the microfluidic chip groove in the center of the bottom plate of the reactor, ensuring that the fluid injection port of the chip is aligned with the chip injection port on the bottom plate, thus completing the initial positioning of the chip. S2. Cover plate closure and pre-fixing; The reaction vessel cover is placed on the base plate, and the cover and base plate are initially fastened with bolts to form a closed reaction vessel cavity. At this time, the chip is in the state of waiting to be attached between the cover and the base plate. S3. Water pressure bonding process; Lower water pressure establishment: Water is injected into the lower water injection cavity of the reactor bottom plate through the water injection channel in the lower groove. After the water fills the cavity, it forms a uniform water pressure on the lower surface of the chip. Upper water pressure establishment: Water is simultaneously injected into the upper water injection cavity of the reactor cover plate through the upper groove water injection channel, so that the upper surface of the chip is subjected to water pressure symmetrical with the lower surface; Isobaric bonding effect: The symmetrical water pressure from the top and bottom presses the chip cover plate and the base plate tightly together, achieving a sealed bonding without sintering, ensuring the stability of the chip structure during high-pressure experiments; S4. Experimental Operation Phase; External fluid is injected into the internal channel of the microfluidic chip through the chip injection port on the base plate to perform experimental operations such as oil displacement and fluid observation. During the experiment, water pressure is continuously applied to the chip surface to maintain the fit and seal, and to prevent the chip from separating or leaking under high pressure.

[0023] The present invention has the following advantages: Disassembly and reusability: The device can be disassembled after the experiment, and the microfluidic chip can be reused, which significantly reduces material consumption and experimental costs.

[0024] Protecting brittle materials: Uniform bonding is achieved through liquid pressure, eliminating stress concentration caused by rigid clamps, effectively preventing the breakage of brittle chips such as quartz glass, and improving experimental stability.

[0025] Easy and efficient operation: No complicated sintering process is required, the assembly and disassembly process is simplified, and the experimental preparation time is shortened; it supports the reuse of the same chip in multiple experiments, which improves the operational flexibility.

[0026] Cleaning and compatibility optimization: The detachable structure facilitates thorough cleaning of residual impurities, reducing the risk of cross-contamination; it is compatible with a variety of chemical reagents and adaptable to complex reaction systems.

[0027] Precision and durability: The injection port is precisely aligned with the chip channel to ensure stable fluid introduction; the base plate and cover plate are made of materials such as 316L stainless steel, which have high pressure resistance and corrosion resistance, and can adapt to harsh experimental environments.

[0028] In summary, this invention responds to the need for improvement in the prior art and proposes a water pressure bonding technology with symmetrical water injection grooves (reactor bottom plate 1, grooves 3 and 7, upper and lower water injection channels 5 and 9), which simultaneously solves the following problems: material waste caused by non-removable sintering (no sintering operation is performed, and the chip can be disassembled and cleaned after the experiment); brittle fracture caused by mechanical clamping; and operational complexity caused by the confining pressure system (no need to apply confining pressure). Thus, while ensuring high pressure stability, it achieves chip reuse and greatly simplifies the experimental process. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of the present invention after half of the structure has been cut off.

[0030] Figure 2 This is a top view of the bottom plate of the reactor.

[0031] Component names and attached drawing labels details 1. Reactor bottom plate 1 Installation location: The bottom of the device, with a microfluidic chip recess 3 in the center.

[0032] Working process: The microfluidic chip is placed in the groove and fastened to the cover plate 2 by bolt structure 10 to form a closed cavity.

[0033] Working principle: As the basic support structure of the device, the lower water pressure is established through the bottom water injection channel 5.

[0034] Technical function: Provides a chip mounting platform and works with the cover plate to achieve water pressure bonding and sealing.

[0035] 2. Reactor cover plate 2 Installation location: The top of the device, with an upper groove 7 on the inner side corresponding to the chip position.

[0036] Working process: After being covered on the base plate 1 and pre-fixed with bolts, water pressure is established through the upper water injection channel 9.

[0037] Working principle: It forms a symmetrical cavity structure with the base plate, and achieves stress-free bonding of the chip through the transmission of liquid pressure.

[0038] Technical function: Provides the upper water pressure cavity 8, which works in conjunction with the bottom plate to achieve equal pressure sealing.

[0039] 3. Microfluidic chip recess 3 Installation location: center of reactor bottom plate 1, with dimensions matching the microfluidic chip.

[0040] Working process: accommodating the chip and initial positioning.

[0041] Working principle: Precise installation is achieved by limiting chip displacement through the size of the groove.

[0042] Technical function: To ensure the chip is fixed in position and to prevent fluid leakage or misalignment during experiments.

[0043] 4. Lower water injection chamber (4) Installation location: between the microfluidic chip groove 3 and the lower surface of the chip.

[0044] Working process: Water is injected through the water injection channel 5 in the lower groove to form a uniform water pressure on the lower surface.

[0045] Working principle: Liquid pressure is applied evenly to the bottom of the chip, replacing rigid clamps to achieve bonding.

[0046] Technical function: To provide lower bonding pressure and prevent the chip from cracking due to stress concentration.

[0047] 5. Lower recessed water injection channel 5 Installation location: at the bottom of the groove 6 on the bottom plate of the reactor, connecting to the lower water injection chamber 4.

[0048] Working process: Connect an external water injection device (such as a micro water pump) to inject water into cavity 4 and adjust the pressure.

[0049] Working principle: Controllable water pressure is established through fluid transmission, and the pressure can be independently adjusted to meet experimental requirements.

[0050] Technical function: To achieve precise control of the lower water pressure and match the upper water pressure to form a symmetrical fit.

[0051] 6. Groove 6 on the bottom plate of the reactor Installation location: Inside the bottom plate 1 of the reactor, surrounding the groove 3 of the microfluidic chip.

[0052] Working process: It serves as a connecting and transitional structure between the lower groove water injection channel 5 and the lower water injection cavity 4.

[0053] Working principle: Guides water flow to be evenly distributed in cavity 4 to avoid sudden changes in local pressure.

[0054] Technical function: To ensure stable water pressure transmission, water injection channel.

[0055] 7. Top plate groove 7 Installation location: Inside the reactor cover plate 2, corresponding to the chip position, symmetrical to the groove 6 on the base plate.

[0056] Working process: Water is injected into the upper water injection cavity 8 through the upper groove water injection channel 9.

[0057] Working principle: Together with the groove 6 on the base plate, it forms a symmetrical water injection structure to achieve equal pressure or pressure-controlled water injection on the upper and lower surfaces of the chip.

[0058] Technical function: To ensure stable water pressure transmission, water injection channel.

[0059] 8. Upper water injection chamber 8 Installation location: Between the top plate groove 7 and the upper surface of the chip.

[0060] Working process: Water is injected through the upper groove water injection channel 9 to form a water pressure symmetrical with the lower cavity 4.

[0061] Working principle: Liquid pressure acts vertically on the top of the chip, and together with the water pressure below, it achieves stress-free bonding.

[0062] Technical function: To balance the stress on the chip and prevent the chip from deforming or separating under high pressure.

[0063] 9. Upper groove water injection channel 9 Installation location: Top of the groove 7 on the top plate, connecting to the upper water injection chamber 8.

[0064] Working process: Connect an external water injection device to inject water into the upper cavity 8 and adjust the pressure independently.

[0065] Working principle: It is symmetrically set with the lower water injection channel 5, and the bonding strength is controlled by the pressure difference.

[0066] Technical function: Water injection channel, assisting in the precise control of upper water pressure to adapt to different experimental pressure requirements.

[0067] 10. Bolted structure 10 Installation location: Evenly distributed along the edge of the reactor, with a minimum of 4 units.

[0068] Working process: Pre-tighten cover plate 2 and base plate 1 to form an initial seal, and assist in fixing when the water pressure is applied.

[0069] Working principle: By using evenly distributed bolt force to avoid local gaps, water pressure leakage is prevented.

[0070] Technical function: To ensure the overall structural stability of the device, suitable for long-term or dynamic pressure tests.

[0071] 11. Chip injection port 11 Installation location: On the bottom plate 1 of the reactor, corresponding to the fluid inlet channel of the microfluidic chip.

[0072] Working process: During the experiment, external fluid is injected into the internal channel of the chip through this port.

[0073] Working principle: Precisely align the fluid inlet of the chip to ensure that the fluid is introduced without leakage.

[0074] Technical function: To improve the reliability of experimental data and avoid fluid leakage, contamination, or pressure loss. Detailed Implementation

[0075] like Figure 1 and Figure 2 As shown, a reaction vessel device for non-sintered quartz glass microfluidic chips according to the present invention includes: The bottom plate 1 of the reactor has a microfluidic chip groove 3 in the center to accommodate the microfluidic chip and form a lower water injection cavity 4; The lower groove water injection channel 5 is located at the bottom of the groove 6 of the reactor bottom plate and is used to inject water into the lower water injection cavity 4 through the groove 6 of the reactor bottom plate; the groove 6 of the reactor bottom plate communicates with the lower water injection cavity 4; The reactor cover plate 2 has an upper groove on the inner side corresponding to the chip position, forming an upper water injection cavity 8; The upper groove water injection channel 9 is located at the top of the top plate groove 7 and is used to inject water into the upper water injection cavity 8; the top plate groove 7 communicates with the upper water injection cavity 8; Bolt structure 10 is used to fasten the reactor cover plate 2 and the reactor bottom plate 1.

[0076] This invention achieves sealing bonding without sintering: the chip is bonded under equal pressure by water pressure in the upper and lower water injection chambers, replacing the traditional sintering process and solving the problems of the chip being non-removable and unreusable after sintering.

[0077] This invention can avoid damage to the chip from rigid clamps: the liquid pressure bonding method avoids stress concentration from external rigid clamps, is suitable for brittle materials such as quartz glass, and reduces the risk of chip breakage.

[0078] This invention improves reusability: after the experiment, the chip can be easily disassembled for thorough cleaning to remove residual impurities, significantly reducing material consumption and experimental costs.

[0079] The size of the microfluidic chip groove 3 is matched with the microfluidic chip, and the bottom plate 1 of the reactor is provided with a chip injection port 11, which corresponds to the fluid inlet channel of the microfluidic chip.

[0080] This invention achieves precise positioning and fluid sealing: the groove size matches the chip to ensure accurate positioning during installation, and the corresponding injection port design avoids leakage of experimental fluids, thus improving the reliability of experimental data.

[0081] The upper groove water injection channel 9 and the lower groove water injection channel 5 are symmetrically arranged, and the water injection pressure can be adjusted independently.

[0082] The symmetrical water pressure of the upper groove water injection channel 9 and the lower groove water injection channel 5 ensures uniform stress on the upper and lower surfaces of the chip, preventing chip separation or deformation during high-pressure injection and reducing the risk of breakage. Independent pressure adjustment can adapt to different experimental pressure requirements. Independent pressure adjustment can be achieved by connecting different water injection devices (such as micro water pumps) to the upper groove water injection channel 9 and the lower groove water injection channel 5 respectively, or by connecting the same water injection device but installing pressure regulating valves upstream of the upper groove water injection channel 9 and the lower groove water injection channel 5. Both are existing technologies and will not be described in detail.

[0083] The bolt structure 10 is evenly distributed along the edge of the reactor, with a quantity of no less than 4.

[0084] The bolt structure 10 has multiple bolts evenly distributed, achieving uniform tightening and reliable sealing; the evenly distributed bolts on the edge ensure that the cover plate and the base plate fit tightly, avoiding water pressure leakage caused by local gaps, and are suitable for long-term or dynamic pressure tests.

[0085] The bottom plate 1 and cover plate 2 of the reactor are made of high pressure resistant and corrosion resistant materials.

[0086] The bottom plate 1 and cover plate 2 of the reactor can be made of metal materials such as stainless steel (e.g., 316L), titanium alloy, nickel-based alloy (e.g., Hastelloy), or engineering plastics such as polytetrafluoroethylene and polyether ether ketone (PEEK), with stainless steel (e.g., 316L) being preferred.

[0087] The high pressure resistance of the reactor bottom plate 1 and cover plate 2 meets the high pressure fluid injection requirements in the petroleum engineering field, and the corrosion resistance prevents experimental fluids (such as crude oil and chemical reagents) from corroding the equipment and extends its service life.

[0088] The detailed working process of this invention is as follows: 1. Chip installation stage The non-sintered quartz glass microfluidic chip is placed in the microfluidic chip groove in the center of the reactor bottom plate, ensuring that the fluid injection port of the chip is aligned with the chip injection port on the bottom plate, thus completing the initial positioning of the chip.

[0089] 2. Cover plate closure and pre-fixing The reactor cover is placed over the base plate, and the cover and base plate are initially fastened with bolts to form a closed reactor cavity. At this time, the chip is in the state of waiting to be bonded between the cover and the base plate.

[0090] 3. Water pressure bonding process Lower water pressure establishment: Water is injected into the lower water injection cavity of the reactor bottom plate through the water injection channel in the lower groove. After the water fills the cavity, it forms a uniform water pressure on the lower surface of the chip.

[0091] Upper water pressure establishment: Water is simultaneously injected into the upper water injection cavity of the reactor cover plate through the upper groove water injection channel, so that the upper surface of the chip is subjected to water pressure symmetrical to the lower surface.

[0092] Isobaric bonding effect: The symmetrical water pressure from the top and bottom presses the chip cover plate and the base plate tightly together, achieving a sealed bonding without sintering, ensuring the stability of the chip structure during high-pressure experiments.

[0093] 4. Experimental Operation Phase External fluid is injected into the internal channels of the microfluidic chip through the chip injection port on the base plate for experiments such as oil displacement and fluid observation. During the experiment, water pressure is continuously applied to the chip surface to maintain adhesion and seal, preventing chip separation or leakage under high pressure.

[0094] 5. Disassembly and cleaning after the experiment Depressurization operation: After the experiment, release the water pressure in the upper and lower water injection chambers to relieve the bonding force on the chip.

[0095] Disassembly and cleaning: Unscrew the bolt structure, separate the cover plate from the base plate, take out the chip and clean it thoroughly to remove residual crude oil, emulsion and other impurities. The cleaned chip can be reused for subsequent experiments.

[0096] Key features, at least for now: Sinter-free reuse: By replacing the traditional sintering process with water pressure bonding, chips can be disassembled and reused without damage, reducing experimental costs.

[0097] Pressure-adaptive sealing: The liquid pressure bonding method avoids the stress concentration problem of rigid clamps, protects brittle glass chips, and adapts to the needs of dynamic pressure experiments.

[0098] Simplified operating procedures: No complex confining pressure system is required under normal temperature and pressure, shortening experimental preparation time and improving platform flexibility.

[0099] The above embodiments are only used to illustrate and not limit the technical solutions of the present invention. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention without departing from the spirit and scope of the present invention. Any modifications or partial substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A reaction vessel device for non-sintered quartz glass microfluidic chips, characterized in that, include: The bottom plate of the reactor (1) has a microfluidic chip groove (3) in the center to accommodate the microfluidic chip and form a lower water injection cavity (4). The lower groove water injection channel (5) is set at the bottom of the bottom plate groove (6) of the reactor. The bottom plate groove (6) of the reactor surrounds the microfluidic chip groove (3) and communicates with the lower water injection cavity (4). It is used to guide the water flow to be evenly distributed to the lower water injection cavity (4) and to inject water into it. The reactor cover plate (2) has an upper groove on the inner side corresponding to the chip position, forming an upper water injection cavity (8). The upper groove water injection channel (9) is set at the top of the top plate groove (7). The top plate groove (7) and the bottom plate groove (6) of the reactor are symmetrically arranged to form a symmetrical water injection structure for injecting water into the upper water injection cavity (8). The top plate groove (7) is connected to the upper water injection cavity (8). Bolt structure (10) is used to pre-tighten the reactor cover plate (2) and the reactor bottom plate (1) to form an initial seal, and to assist in fixing during water pressure bonding; The lower water injection cavity (4) and the upper water injection cavity (8) use liquid pressure to perform isobaric bonding of the chip, thereby achieving stress-free bonding and sealing.

2. The reaction vessel device for non-sintered quartz glass microfluidic chips according to claim 1, characterized in that, The size of the microfluidic chip groove (3) matches the microfluidic chip, and the bottom plate (1) of the reactor is provided with a chip injection port (11), which corresponds to the fluid inlet channel of the microfluidic chip.

3. The reaction vessel device for non-sintered quartz glass microfluidic chips according to claim 1, characterized in that, The water injection pressure of the upper groove water injection channel (9) and the lower groove water injection channel (5) can be adjusted independently.

4. The reaction vessel device for non-sintered quartz glass microfluidic chips according to claim 1, characterized in that, The bolt structure (10) is evenly distributed along the edge of the reactor, with a quantity of no less than 4.

5. The reaction vessel device for non-sintered quartz glass microfluidic chips according to claim 1, characterized in that, The bottom plate (1) and cover plate (2) of the reactor are made of high pressure resistant and corrosion resistant materials.

6. Experimental method: The experimental procedure is carried out using the reaction vessel apparatus for non-sintered quartz glass microfluidic chips described in claim 2, following these steps: S1. Chip installation stage; The non-sintered quartz glass microfluidic chip is placed in the microfluidic chip groove in the center of the bottom plate of the reactor, ensuring that the fluid injection port of the chip is aligned with the chip injection port on the bottom plate, thus completing the initial positioning of the chip. S2. Cover plate closure and pre-fixing; The reaction vessel cover is placed on the base plate, and the cover and base plate are initially fastened with bolts to form a closed reaction vessel cavity. At this time, the chip is in the state of waiting to be attached between the cover and the base plate. S3. Water pressure bonding process; Lower water pressure establishment: Water is injected into the lower water injection cavity of the reactor bottom plate through the water injection channel in the lower groove. After the water fills the cavity, it forms a uniform water pressure on the lower surface of the chip. Upper water pressure establishment: Water is simultaneously injected into the upper water injection cavity of the reactor cover plate through the upper groove water injection channel, so that the upper surface of the chip is subjected to water pressure symmetrical with the lower surface; Isobaric bonding effect: The symmetrical water pressure from the top and bottom presses the chip cover plate and the base plate tightly together, achieving a sealed bonding without sintering, ensuring the stability of the chip structure during high-pressure experiments; S4. Experimental Operation Phase; External fluid is injected into the internal channel of the microfluidic chip through the chip injection port on the base plate to perform oil displacement and fluid observation experiments. During the experiment, water pressure is continuously applied to the chip surface to maintain the fit and seal, and to prevent the chip from separating or leaking under high pressure.

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