A device and method for simulating dynamic hydrate accumulation under temperature field decline background

Abstract

This invention discloses a device and method for simulating dynamic hydrate accumulation under a temperature field decline background, belonging to the technical field of natural gas hydrates. The device includes a reaction chamber, a muddipriller simulator, and a gas supply assembly. The reaction chamber has a reaction cavity containing multiple sedimentary layers filled with packing particles. At least one side wall of the reaction chamber is a cooling wall, with a cavity for containing coolant. The muddipriller simulator includes a diffusion section. Along the direction from the bottom to the top of the reaction chamber, the cross-sectional area of ​​the guide channel gradually increases, allowing alkane gas to diffuse and spread within the diffusion area, thereby simulating the migration of deep gas-bearing fluids to shallow reservoirs under a temperature field decline background. Through the reaction chamber, muddipriller simulator, and gas supply assembly, the formation and evolution process of hydrates under a temperature field decline background can be simulated.

Description

Technical Field

[0001] This invention belongs to the technical field of natural gas hydrates, and specifically relates to a device and method for simulating dynamic accumulation of hydrates under the background of temperature field decline. Background Technology

[0002] Natural gas hydrates, as a new type of clean energy, have the advantages of high efficiency, low carbon emissions, and huge resource reserves.

[0003] Most existing hydrate dynamic accumulation simulation devices can only preliminarily simulate deep thermal fluid activities, such as gas chimneys and mud diapirs, as well as their geological processes, and focus on the basic changes in the stability domain during the increase of geothermal gradient. They are unable to fully analyze the complex evolution mechanism and have insufficient physical simulation of real geological elements and actual geological conditions. In particular, the simulation capability needs to be strengthened for the dynamic evolution of the stability domain under the background of geothermal field decline during the intermittent period of multiple fluid activities. Summary of the Invention

[0004] The purpose of this invention is to provide a hydrate dynamic accumulation simulation device under the background of temperature field decline, which can simulate the migration of deep gas-bearing fluids to shallow reservoirs under the background of temperature field decline, and realize the simulation of the formation and evolution process of hydrates under the background of temperature field decline.

[0005] This invention also provides a method for simulating the evolution of seepage-type hydrate accumulation.

[0006] The technical solution adopted to solve the above-mentioned technical problems is as follows:

[0007] The first aspect of this invention provides a device for simulating dynamic hydrate accumulation under a temperature field decline background, comprising:

[0008] A reaction chamber has a reaction cavity, which is provided with multiple deposition layers arranged along the height direction of the reaction chamber; the deposition layers are filled with filler particles; at least one side wall of the reaction chamber is a cooling wall, and the cooling wall is provided with a receiving cavity for containing coolant;

[0009] A mud diverter simulator includes a diffusion section; the diffusion section is provided with a guide channel and an outlet communicating with the guide channel, the outlet being located at the top of the diffusion section; the diffusion section is located inside the reaction chamber, and a diffusion area is formed above the diffusion section, the diffusion area being located within at least one of the deposition layers; the cross-sectional area of ​​the guide channel gradually increases along the direction from the bottom to the top of the reaction chamber;

[0010] A gas supply assembly is connected to the guide channel and is used to supply alkane gases to the guide channel.

[0011] An embodiment of the present invention provides a sensor assembly, wherein the muddipractic simulator includes multiple simulation tubes, the simulation tubes are located within the guide channel and are connected to the gas supply assembly; along the direction from the bottom to the top of the muddipractic simulator, the simulation tubes bend from the middle of the guide channel toward the edge of the guide channel.

[0012] An embodiment of the present invention provides a sensor assembly in which at least two of the analog tubes are arranged alternately.

[0013] An embodiment of the present invention provides a sensor assembly in which the wall of the analog tube is provided with a main crack, the main crack including multiple bends, the multiple bends being arranged along the extension direction of the analog tube, and the extension directions of two adjacent bends being different.

[0014] An embodiment of the present invention provides a sensor assembly in which the wall of the analog tube is provided with multiple branch cracks, and the branch cracks are connected to the main crack.

[0015] An embodiment of the present invention provides a sensor assembly, wherein the mud diverter simulator further includes a housing, the housing being filled with filler particles; the housing is provided with an air intake channel and an air inlet communicating with the air intake channel, and a guide channel is disposed within the housing and communicates with the air intake channel.

[0016] An embodiment of the present invention provides a sensor assembly, wherein the gas supply assembly includes a gas mixing pipe and multiple gas storage containers, the multiple gas storage containers being used to contain different gases; the inlet end of the gas mixing pipe is connected to the multiple gas storage containers, and the outlet end of the gas mixing pipe is connected to the guide channel; multiple stirrers are provided inside the gas mixing pipe, the stirrers being used to mix the gas inside the gas mixing pipe.

[0017] An embodiment of the present invention provides a sensor assembly, wherein the simulation device further includes multiple heating elements and multiple temperature sensors. The multiple heating elements are disposed in the reaction chamber along the height direction of the reaction chamber, and the multiple temperature sensors are disposed in the reaction chamber along the height direction of the reaction chamber. Each deposition layer is provided with at least one heating element and at least one temperature sensor.

[0018] An embodiment of the present invention provides a sensor assembly in which a reaction chamber is provided with multiple cooling walls, and the multiple cooling walls surround to form the reaction chamber.

[0019] A second aspect of the present invention provides a method for simulating dynamic hydrate accumulation under a temperature field decline background, applied to a simulating device for dynamic hydrate accumulation under a temperature field decline background provided in the first aspect of the present invention, comprising:

[0020] Water with a sodium chloride content of 3.5% (by weight) is injected into the reaction chamber;

[0021] Coolant is introduced into the cavity containing the cooling wall;

[0022] Alkane gas is introduced into the guide channel through a gas supply component. Attached Figure Description

[0023] The present invention will be further described below with reference to the accompanying drawings and embodiments;

[0024] Figure 1 This is a schematic diagram of the overall structure of the reaction chamber of the hydrate dynamic accumulation simulation device under the background of temperature field decline provided in the embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the reaction chamber of the hydrate dynamic accumulation simulation device under the background of temperature field decline provided in the embodiments of the present invention;

[0026] Figure 3 This is a schematic diagram of the structure of the mud diapir simulator of the hydrate dynamic accumulation simulation device under the temperature field decline background provided in the embodiment of the present invention;

[0027] Figure 4 This is one of the schematic diagrams of the simulation tube structure of the hydrate dynamic accumulation simulation device under the temperature field decline background provided in the embodiments of the present invention;

[0028] Figure 5 This is the second schematic diagram of the structure of the simulation tube of the hydrate dynamic accumulation simulation device under the temperature field decline background provided in the embodiments of the present invention;

[0029] Figure 6 This is a schematic diagram of the gas supply component of the hydrate dynamic accumulation simulation device under temperature field decline background provided in the embodiments of the present invention;

[0030] Figure 7 This is a schematic diagram of the coordination relationship between the gas mixing pipe and the mud diapir simulator of the hydrate dynamic accumulation simulation device under the background of temperature field decline provided in the embodiment of the present invention;

[0031] Figure 8 This is a schematic diagram of the laser Raman detection component of the hydrate dynamic accumulation simulation device under temperature field decline background provided in the embodiments of the present invention;

[0032] The following labels are shown in the attached diagram:

[0033] 100. Reaction chamber; 110. Reaction cavity; 120. Deposition layer; 121. First deposition layer; 122. Second deposition layer; 123. Third deposition layer; 130. Cooling wall; 131. Reception cavity; 140. Partition;

[0034] 200. Dipipe simulator; 210. Diffusion section; 211. Guide channel; 212. Air outlet; 213. Diffusion protrusion; 220. Diffusion area; 230. Air inlet; 231. Air inlet; 232. Air inlet channel; 240. Simulation tube; 241. Main crack; 2411. Bending section; 242. Sub-crack; 250. Outer shell; 260. Impedance sensor;

[0035] 300. Gas supply assembly; 310. Gas mixing pipeline; 311. Control valve; 320. Gas storage container; 330. Agitator;

[0036] 400. Filler particles;

[0037] 510. Heating element; 520. Column;

[0038] 600. Monitoring components; 610. Monitoring sensors; 620. Mounting posts;

[0039] 700. Laser Raman detection assembly; 710. Laser emitter; 720. Filter group; 730. Spectrometer;

[0040] 800 Cooling assembly; 810 Drive pump; 820 Storage container; 830 Inlet pipe; 840 Outlet pipe; 850 Cryogenic controller. Detailed Implementation

[0041] This section will describe in detail specific embodiments of the present invention. Preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the drawings is to supplement the textual description with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present invention, but they should not be construed as limiting the scope of protection of the present invention.

[0042] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0043] In the description of this invention, the use of terms such as "a number" means one or more, with "more than" meaning two or more. Terms like "greater than," "less than," and "exceeding" are understood to exclude the stated number, while terms like "above," "below," and "within" are understood to include the stated number. The use of terms like "first," "second," and "third" is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, the number of indicated technical features, or the sequential relationship between indicated technical features.

[0044] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0045] Under normal circumstances, a seafloor simulated reflection layer (BSR) appears in seismic profiles of hydrate-bearing areas. The formation of the BSR stems from the impedance difference between the upper hydrate and the lower gas layer. This difference causes strong reflection of seismic waves, creating a distinct reflection interface. In the field of hydrate exploration, the BSR is a crucial geophysical indicator, serving as an important basis for guiding hydrate exploration and drilling. With the continuous advancement of hydrate exploration, double BSRs have been discovered in an increasing number of marine seismic profiles, such as in the Nankai Trough Basin of Japan, the Black Sea, the Caspian Sea, and the Barents Sea of ​​Norway. Current research suggests that the double BSR is essentially influenced by the dynamic evolution of hydrates and the spatially differentiated distribution of hydrates and free gas. From a dynamic mechanism perspective, factors including global climate change and its resulting seafloor temperature changes, sedimentary erosion, loading, and deep-sea thermal fluid activity may all contribute to the dynamic evolution of hydrates (stability domain migration) and the formation of double BSRs.

[0046] Gas-bearing hydrothermal activity, as a key and ubiquitous geological factor, profoundly influences the spatial migration and evolution of natural gas hydrate stability domains and the distribution patterns of hydrates. This influence has been thoroughly verified, particularly in the exploration of natural gas hydrates in the South China Sea, where the complexity of its mechanisms and the breadth of its impact have been well-documented. Studies on the migration of hydrate stability domains induced by hydrothermal activity primarily rely on seismic data analysis, supplemented by physical simulation experiments. These studies typically view hydrothermal activity as a destructive effect under high heat flux conditions, focusing on the upward migration of hydrate stability domains and the thinning or even decomposition of hydrate layers after normal sedimentary strata are disturbed by hydrothermal activity, leading to increased formation temperature. In conventional understanding, upward migration of hydrate stability domains is more common. This upward migration causes the decomposition of existing hydrates due to changes in temperature and pressure, releasing gases that migrate upwards and dissipate, then re-accumulate in new stability domains to form hydrates. In actual geological evolution, gas-bearing hydrothermal activity often exhibits a periodic (episodic) characteristic, with long time intervals between two episodes of fluid activity. After a single thermal fluid activity occurs under overpressure, the energy (heat) gradually decreases over time, and the fluid transport rate also decreases. This change directly weakens the thermal convection effect of the fluid during transport, as well as its ability to carry heat through flow. Under real geological conditions, temperature field decay due to weakened thermal fluid activity is common. This temperature field decay inevitably triggers dynamic changes in hydrate stability domains, prompting them to migrate downwards, thereby altering the hydrate accumulation process and spatial enrichment patterns. The downward migration process of hydrate stability domains and BSRs, as well as the accompanying dynamic evolution of hydrates, has received relatively little attention in previous studies. The downward migration of hydrate stability domains is essentially a process of expanding the space of hydrate stability domains. This process not only does not cause the decomposition and destruction of upper hydrates, but also promotes the continuous growth of upper hydrates and their continuous downward extension. From the perspective of hydrate resource assessment, this special growth pattern contains enormous research value and resource potential. However, current technology lacks hydrate accumulation simulation devices under the background of temperature field decay. Based on this, this application focuses on the background of temperature field decline under the control of episodic fluid activity, and designs a hydrate accumulation simulation device under the background of temperature field decline, and innovates the experimental method system. It aims to provide theoretical basis and reliable technical support for revealing the hydrate accumulation mechanism under the background of temperature field decline, so as to explore the downward migration process of hydrate stability domain and the multi-stage dynamic accumulation evolution law of hydrate under the background of temperature field decline.

[0047] Existing experimental simulation devices, constrained by their structure and simulation capabilities, primarily focus on simulating sedimentation rates, hydrostatic pressure, or geothermal gradient changes. Most can only preliminarily simulate deep hydrothermal activity, such as gas chimneys and mud diapirs, and their geological processes. They focus on the fundamental changes in the stability domain during periods of increasing geothermal gradients, failing to comprehensively analyze its complex evolutionary mechanisms. Some studies rely mainly on numerical simulations, which are insufficient for physically simulating real geological elements and actual geological conditions. Furthermore, existing experimental simulation devices often explore hydrate stability domain evolution around single factors such as sedimentation rates, hydrostatic pressure, and geothermal gradient changes, lacking sufficient research on the dynamic evolution mechanisms of hydrates under conditions of temperature field decline. There is room for improvement in accurately reflecting real geological backgrounds, particularly regarding the dynamic evolution of stability domains during periods of geothermal field decline in the intermittent phases of multi-stage fluid activity. Meanwhile, current devices rely on limited methods for simulating temperature decay, primarily direct temperature control. This makes it difficult to reproduce the geothermal field decay effect caused by weakened deep thermal fluid activity, and hinders the accurate simulation of the coupling relationship between temperature decay and fluid activity, thus limiting the analysis of key processes in hydrate evolution. At the monitoring level, existing experimental simulation devices mostly employ conventional combinations of resistivity, temperature, and pressure sensors, making it difficult to achieve refined real-time monitoring of multi-phase, episodic thermal fluid activity and the evolution of fluid stability domains under geothermal field decay. They often rely on single-factor or traditional physical monitoring based on acoustic or electrical signals, lacking multi-dimensional collaborative monitoring of hydrate microstructure changes and temperature field distribution. This makes it impossible to establish a quantitative correlation between temperature field changes and hydrate evolution, failing to meet the data requirements of high-precision experiments. Regarding multi-parameter collaborative control, existing devices lack dynamic coupling control of temperature field, fluid transport, and pressure changes, making it difficult to simulate the hydrate evolution process under the synergistic effects of multiple factors in real geological scenarios. Furthermore, the temperature field control precision is insufficient, and traditional sensor feedback adjustment cannot achieve precise control of temperature gradients and local thermal anomalies.

[0048] Reference Figures 1 to 8 The following are several embodiments of a device and method for simulating dynamic hydrate accumulation under a temperature field decline background according to the present invention.

[0049] like Figures 1 to 3As shown, a hydrate dynamic accumulation simulation device under a temperature field decline background according to a first aspect embodiment of the present invention includes a reaction chamber 100, a muddiprairie simulator 200, and a gas supply assembly 300. The reaction chamber 100 has a reaction cavity 110, and the reaction cavity 110 is provided with multiple deposition layers 120, which are arranged along the height direction of the reaction chamber 100. The deposition layers 120 are filled with filling particles 400. At least one side wall of the reaction chamber 100 is a cooling wall 130, and the cooling wall 130 is provided with a receiving cavity 131 for containing coolant. The muddiprairie simulator 200 includes an expansion... The diffuser 210 is provided with a guide channel 211 and an outlet 212 communicating with the guide channel 211. The outlet 212 is located at the top of the diffuser 210. The diffuser 210 is located inside the reaction chamber 100, and a diffusion region 220 is formed above the diffuser 210. The diffusion region 220 is located within at least one deposition layer 120. The cross-sectional area of ​​the guide channel 211 gradually increases along the direction from the bottom to the top of the reaction chamber 100. The gas supply assembly 300 is connected to the guide channel 211 and is used to supply alkane gas to the guide channel 211.

[0050] Water is introduced into the reaction chamber 110, and multiple sedimentary layers 120 are arranged along the height of the reaction chamber 100, with filling particles 400 inside each sedimentary layer 120. The multiple sedimentary layers 120 recreate the real geological structure characteristics of the shallow deep-sea layer. Coolant is located inside the cooling wall 130 to reduce the temperature inside the reaction chamber 110, thereby simulating the deep-sea temperature. Alkane gas is introduced into the guide channel 211 through the gas supply component 300. Along the direction from the bottom to the top of the reaction chamber 100, the cross-sectional area of ​​the guide channel 211 gradually increases, causing the alkane gas diffuser 210 to diffuse and spread in the diffusion area 220, thereby simulating the state of deep gas-bearing fluids migrating to shallow reservoirs under the background of temperature field decline. Through the reaction chamber 100, the mud diapir simulator 200, and the gas supply component 300, the formation and evolution process of hydrates under the background of temperature field decline is simulated.

[0051] The reaction chamber 100 is the key spatial area for simulating hydrate accumulation. By adjusting the water injection volume into the reaction chamber 110, precise control of the internal pressure can be achieved, creating a uniform high-pressure environment within the chamber to simulate the high-pressure environment of a real ocean. Typically, the internal pressure of the reaction chamber 110 is stable above 15 MPa. The reaction chamber 100 is cuboid in shape for ease of fabrication. Made of high-strength transparent plexiglass, it not only possesses excellent pressure resistance, adapting to the overall high-pressure environment, but also exhibits excellent light transmittance, facilitating the visualization and observation of hydrate formation, evolution, and fluid transport phenomena during experiments. To further enhance the structural stability of the reaction chamber 100, a stainless steel frame can be installed externally for reinforcement, ensuring that the chamber will not deform or be damaged under simulated high-pressure conditions.

[0052] like Figures 1 to 2 As shown, multiple baffles 140 are arranged inside the reaction chamber 110 along the height direction of the reaction chamber 100 to divide the reaction chamber 110 into multiple deposition layers 120. That is, the baffles 140 are positioned between adjacent deposition layers 120 to confine the filler particles 400 within the corresponding deposition layer 120. The baffles 140 have through holes to allow gas and liquid to pass through. The baffles 140 divide the reaction chamber 110 into different deposition layers 120, and the filler particles 400 are filled into the deposition layers 120, facilitating assembly. Generally, the filler particles 400 are made of materials such as ceramsite or quartz sand. It should be noted that the diameter of the filler particles 400 is larger than the diameter of the through holes to prevent the filler particles 400 from passing through the through holes. In this embodiment, three sedimentation layers 120 are provided, namely a first sedimentation layer 121, a second sedimentation layer 122, and a third sedimentation layer 123; the first sedimentation layer 121, the second sedimentation layer 122, and the third sedimentation layer 123 are arranged sequentially from the bottom to the top of the reaction chamber 100; the first sedimentation layer 121 is filled with first filler particles to simulate a reservoir with good deep permeability, which is conducive to fluid migration and permeation; the second sedimentation layer 122 is filled with second filler particles to simulate a middle reservoir, and the diameter of the second filler particles is smaller than that of the first filler particles to adapt to the formation and stable storage of hydrates; the third sedimentation layer 123 is filled with third filler particles to simulate a capping layer with a sealing function, which can effectively prevent gas from escaping upwards and provide favorable conditions for the preservation of hydrates; the diameter of the third filler particles is smaller than that of the second filler particles, which is conducive to preventing gas from escaping upwards. By using filler particles 400 of different sizes and partitions 140, the permeability differences of different layers in the real marine geological environment can be approximately and realistically reproduced, laying the foundation for simulating the migration of fluids in different strata and the accumulation process of hydrates.

[0053] like Figures 1 to 3As shown, at least one side wall of the reaction chamber 100 is a cooling wall 130, and the cooling wall 130 has a receiving cavity 131 for containing coolant; by introducing coolant into the receiving cavity 131, the temperature inside the reaction chamber 110 can be rapidly reduced; since at least one side wall of the reaction chamber 100 is a cooling wall 130, the cooling wall 130 is fitted into the reaction chamber 110, thereby improving the cooling efficiency of the cooling wall 130. Figure 3 As shown, the diffuser 210 is provided with a guide channel 211 and an outlet 212 connecting the guide channel 211, with the outlet 212 located at the top of the diffuser 210. The cross-sectional area of ​​the guide channel 211 gradually increases along the direction from the bottom to the top of the reaction chamber 100. The gas supply assembly 300 supplies alkane gas to the guide channel 211, which guides the flow of the alkane gas, causing it to diffuse within the diffuser 210. In other words, the alkane gas flows along the direction from the bottom to the top of the reaction chamber 110, while simultaneously diffusing from the middle of the guide channel 211 towards its edge, simulating the migration of deep gas-bearing fluids to shallow reservoirs under conditions of temperature field decay. After diffusing within the guide channel 211, the alkane gas flows through the outlet 212 at the top of the diffuser 210 into the sedimentation layer 120. The diffusion region 220 is located within at least one deposition layer 120. In this embodiment, the diffusion part 210 penetrates the first deposition layer 121 and the second deposition layer 122. The top of the diffusion part 210 forms the diffusion region 220, that is, the upper part of the second deposition layer 122 and the third deposition layer 123 are the diffusion region 220, so as to simulate the formation and evolution process of hydrates under the background of temperature field decline.

[0054] like Figure 3 As shown, in this embodiment, the diapir simulator 200 further includes an air inlet 230, which is connected to a diffuser 210. The air inlet 230 is provided with an air inlet 231 and an air inlet channel 232. The air inlet channel 232 connects the air inlet 231 and a guide channel 211. The gas supply assembly 300 supplies alkane gas to the guide channel 211 through the air inlet 231. A fixing hole is provided at the bottom of the reaction chamber 110. The diapir simulator 200 passes through the fixing hole, and the air inlet 231 is located below the reaction chamber 100. The diffuser 210 is located inside the reaction chamber 110.

[0055] like Figure 3 As shown, in some embodiments, the muddipper simulator 200 includes a plurality of simulation tubes 240 located within a guide channel 211 and in communication with a gas supply assembly 300; the simulation tubes 240 bend from the middle of the guide channel 211 toward the edge of the guide channel 211 along a direction from the bottom to the top of the muddipper simulator 200.

[0056] The gas supply assembly 300 supplies alkane gas to the simulation tube 240, which guides the alkane gas, facilitating its uniform diffusion. Along the direction from the bottom to the top of the muddipper simulator 200, the simulation tube 240 bends from the middle of the guide channel 211 towards its edge, causing the alkane gas within the simulation tube 240 to flow from the bottom to the top of the reaction chamber 110, while simultaneously diffusing from the middle of the guide channel 211 towards its edge, simulating the migration of deep gas-bearing fluids to shallow reservoirs under conditions of temperature field decline. Multiple simulation tubes 240 further guide the flow path of the alkane gas, resulting in a more uniform distribution of the alkane gas within the diffuser section 210.

[0057] like Figure 1 and Figure 3 As shown, in some embodiments, at least two simulated tubes 240 are staggered to increase the flow direction of alkane gases, ensuring uniform distribution of alkane gases within the diffusion region 220. In this embodiment, the simulated tubes 240 have a first end and a second end. The first ends of multiple simulated tubes 240 are located within the inlet channel 232. The gas supply assembly 300 delivers alkane gases through the inlet channel 232, allowing the alkane gases to enter both the inlet channel 232 and the simulated tubes 240. The staggered arrangement of multiple simulated tubes 240 forms a stable and robust mesh structure, providing strong support and reinforcement. The second ends of the simulated tubes 240 extend to the top of the diffuser 210, and the gas flows out from the second ends of the simulated tubes 240 and flows into the deposition layer 120 through the outlet 212. Figures 3 to 5As shown, in some embodiments, the simulated tube 240 has a main crack 241 in its wall. Gas flows inside the simulated tube 240 and overflows through the main crack 241 in the tube wall. The simulated tube 240 guides the gas to flow along its extension direction. Simultaneously, some gas flows through the main crack 241 in the tube wall into the guide channel 211, preventing excessive gas concentration in the simulated tube 240 and making the gas distribution within the diapir simulator 200 more uniform. The main crack 241 includes multiple bends 2411, which are arranged along the extension direction of the simulated tube 240, with adjacent bends extending in different directions. When gas flows out through the multiple bends 2411 in the simulated tube 240, multiple branch paths are added to the gas flow path, resulting in multiple radial splits of the gas in the direction perpendicular to the main flow, thus improving the uniformity of gas distribution. The simulation tube 240 has multiple branch cracks 242 on its wall, which are connected to the main crack 241. Gas inside the simulation tube 240 can flow through the branch cracks 242 into the guide channel 211, increasing the diversity of gas flow paths and improving the realism of the simulation of deep gas-bearing fluids. In this embodiment, the branch cracks 242 include a first branch crack and a second branch crack. One end of the first branch crack is connected to the main crack 241, and one end of the second branch crack is connected to the first branch crack. The main crack 241, the first branch crack, and the second branch crack increase the diversity of gas flow paths, which is beneficial for simulating deep gas-bearing fluids. The mud diapir simulator 200 also includes a shell 250 filled with filler particles 400. The guide channel 211 is disposed inside the shell 250, and the air inlet channel 232 and the air inlet 231 are disposed inside the shell 250. The outer shell 250 is filled with filler particles 400. That is, both the air intake channel 232 and the guide channel 211 are filled with filler particles 400. Gas enters the air intake channel 232 through the air intake port 231 and flows into the sediment layer 120 through the guide channel 211 and the air outlet 212 to better simulate the process of deep gas-bearing fluids migrating to shallow reservoirs. The diameter of the filler particles 400 in the outer shell 250 can be designed according to actual needs.

[0058] The muddiprairie simulator 200 serves as a crucial conduit for simulating the migration of deep gas-bearing fluids to shallow reservoirs, realistically reproducing the morphological characteristics and fluid migration patterns of deep-sea muddiprairie structures. As a key geological carrier connecting the gas supply component 300, the muddiprairie simulator 200 plays a vital bridging and guiding role in the hydrate dynamic accumulation simulation device under the entire temperature field decline background. The outer shell 250 is made of high-strength transparent plexiglass. Based on the characteristics of muddiprairie structures in real geological environments, the outer shell 250 is designed with a mushroom-like structure that is narrow at the bottom and wide at the top. This accurately reproduces the multi-directional radial diffusion process triggered by pressure release when deep gas-bearing fluids migrate to shallow layers, realistically reflecting the geological characteristics of fluid transitioning from vertical migration to horizontal diffusion and ultimately breaking through the overlying strata. The guiding channel 211 is a narrow-necked deep channel with a diameter that gradually increases slightly upwards from the bottom of the reaction chamber 100, facilitating upward fluid movement under high pressure and gradual pressure dispersion. The top of the diffuser 210 is provided with a diffusion protrusion 213, and an outlet 212 is located on the diffusion protrusion 213. The diameter of the diffusion protrusion 213 is larger than that of the bottom of the diffuser 210, simulating the phenomenon of deep fluid pressure release followed by lateral diffusion into the shallow reservoir, allowing the fluid to fully diffuse and leak into the surrounding reservoir. In this embodiment, the outer shell 250 includes a top plate, a bottom plate, and side plates, with the side plates connecting the top and bottom plates. The bottom plate is a circular flat plate, while the side and top plates are curved panels. An air inlet 231 is provided on the bottom plate, and the top plate protrudes upwards to form the diffusion protrusion 213. Multiple air outlets 212 are provided on the top plate. The main fracture 241 and secondary fractures 242 are used to simulate a real reservoir fracture system and are important channels for fluid movement. The main fracture 241 extends upwards from the bottom of the simulation tube 240 to the diffusion protrusion 213, while multiple sub-fractures 242 exhibit a network-like distribution, closely resembling the characteristics of real reservoir fractures. Along the direction from the bottom to the top of the simulation tube 240, the width of the main fracture 241 and sub-fractures 242 gradually increases to approximate the physical characteristics of real reservoir fractures, effectively simulating the seepage characteristics of fluids within the fractures. An impedance sensor 260 can be embedded in the fracture. The impedance sensor 260 reflects changes in the gas-water ratio by monitoring changes in the conductivity of the fluid within the fracture, enabling comprehensive analysis of the impact of the fracture system on gas migration paths, flow distribution, and temperature field distribution, providing key parameter support for hydrate stability domain simulation. This embodiment of the invention also includes a control system electrically connected to the impedance sensor 260 to monitor and transmit the conductivity of the fluid within the fracture in real time.

[0059] like Figure 6 and Figure 7As shown, in some embodiments, the gas supply assembly 300 includes a mixing pipe 310 and multiple gas storage containers 320, which are used to hold different gases. The inlet end of the mixing pipe 310 is connected to the multiple gas storage containers 320, and the outlet end of the mixing pipe 310 is connected to the guide channel 211. Different gases are introduced into the mixing pipe 310 through the multiple gas storage containers 320, and the various gases are mixed in the mixing pipe before entering the guide channel 211. The gas storage container 320 is a high-pressure gas tank, and a valve is installed at the outlet of the high-pressure gas tank to control the opening and closing of the high-pressure gas tank. In this embodiment, four gas storage containers 320 are provided, which respectively store methane, ethane, propane, and a backup buffer gas (e.g., carbon dioxide). These gases are the main components of deep-sea natural gas hydrates, and mixing them in different proportions can simulate the gas source characteristics under different geological conditions. A pressure sensor can be installed at the outlet of the high-pressure gas tank to detect the internal pressure of the high-pressure gas tank in real time. The control system is electrically connected to the valves and pressure sensors of the high-pressure gas tank. Operators adjust the valve openings through the control system to precisely control the gas supply to each gas storage container 320 according to the experimental plan, ensuring that the proportions of the mixed gas components meet the requirements. The mixed gas is transported to the guide pipe via the mixing pipe 310. Multiple stirrers 330 are installed inside the mixing pipe 310 to mix the gas within it. Continuous agitation ensures thorough mixing of the multi-component gases, preventing gas fractionation. The mixing pipe 310 can be a pressure-resistant polytetrafluoroethylene (PTFE) pipeline to adapt to high-pressure environments and provide good corrosion resistance. The stirrer 330 includes a micro motor and stirring blades. The output shaft of the micro motor is connected to the stirring blades, driving the blades to rotate and thus mixing the gas in the mixing pipe. Multiple stirrers 330 are arranged in the gas mixing pipe 310, with at least two stirrers 330 rotating in different directions to ensure more uniform gas mixing. For example, some stirrers 330 rotate about the axial direction of the gas mixing pipe 310, while others rotate about the radial direction. The gas mixing pipe 310 includes three mixing sections, with adjacent sections connected and bends to improve mixing efficiency and uniformity. The gas supply component 300 is the gas supply module required for hydrate formation. It provides a precisely proportioned multi-component gas source to the muddiprairie simulator 200, serving as the material basis for simulating fluid activity and hydrate formation, and directly affecting the realism and accuracy of hydrate accumulation simulation.Furthermore, a heating wire and a temperature sensor can be installed inside the gas mixing pipe 310. The control system is electrically connected to the heating wire and temperature sensor, which helps maintain the gas in the gas mixing pipe 310 at a constant initial temperature. A control valve 311 and a temperature sensor are installed at the outlet end of the gas mixing pipe 310. The control valve 311 controls the rate at which the gas flows into the mud diapir simulator 200. By precisely adjusting the fluid injection rate, the evolution of the temperature field is indirectly affected, which is a key link in realizing the coordinated simulation of "fluid rate-temperature field" and plays a crucial role in simulating the hydrate evolution process driven by the decay of the temperature field. The control system is electrically connected to the control valve 311 and the temperature sensor at the outlet end of the gas mixing pipe 310. By changing the opening degree of the control valve 311, the fluid throughput is precisely controlled, thereby achieving continuous adjustment of the fluid rate. The temperature sensor can monitor the temperature of the fluid flowing through the control valve 311 in real time.

[0060] During the experiment, the control system, based on the experimental setup, adjusts the fluid flow rate into the muddipil simulator 200 via control valve 311 to achieve precise control of the fluid filling rate. Its mechanism is based on a logic chain of "rate adjustment → convective heat transfer change → temperature field evolution." By adjusting the fluid filling rate, it changes the heat carried by the fluid and the intensity of convective heat transfer, thereby affecting the amount of heat input from deep to shallow layers. This causes the shallow temperature field to evolve from an initially high state to a natural decline, thus simulating the evolution of the temperature field in real geological processes. The gas temperature inside the mixing pipe is high; the faster the fluid flow rate into the muddipil simulator 200, the higher the internal temperature of the simulator. For example, with "high rate + high temperature fluid" or "low rate + low temperature fluid," the control system can automatically switch operating parameters according to a time sequence without manual intervention. For instance, when simulating short-term thermal fluid activity, it automatically sets a high flow rate and high temperature and maintains them for a certain duration, then automatically switches to low flow rate and low temperature parameters to simulate long-term temperature field decline, improving experimental efficiency and simulation realism. During the process, the temperature sensor at the outlet of the mixing pipe 310 monitors the temperature of the fluid entering the muddier simulation system in real time and feeds the monitoring data back to the control system in real time. The control system analyzes this temperature data to ensure that the temperature field evolution caused by the fluid rate change conforms to the geological laws of the deep sea. When the temperature change is found to deviate from the expected value, the fluid rate or the parameters of the temperature control system will be fine-tuned through the feedback mechanism, so as to achieve accurate simulation of the evolution process of the shallow seabed temperature field under the influence of fluid activity.

[0061] like Figure 2As shown, in some embodiments, the simulation device further includes multiple heating elements 510 and multiple temperature sensors. The multiple heating elements 510 are arranged in the reaction chamber 110 along the height direction of the reaction chamber 100, and the multiple temperature sensors are arranged in the reaction chamber 110 along the height direction of the reaction chamber 100. Each sedimentary layer 120 is provided with at least one heating element 510 and at least one temperature sensor. By heating different sedimentary layers 120 with different heating elements 510, the temperatures of different sedimentary layers 120 are different, which can accurately simulate the geothermal gradient change from the seabed to the reservoir in the deep sea shallow layer. The multiple temperature sensors are arranged in the reaction chamber 110 along the height direction of the reaction chamber 100 to obtain the temperature at different heights of the reaction chamber 110 in real time. The provision of at least one heating element 510 and at least one temperature sensor in each sedimentary layer 120 can ensure that each sedimentary layer 120 is individually measured and controlled. The simulation device also includes a column 520, which is vertically installed inside the reaction chamber 110. The partition plate 140 has perforations for the column 520 to pass through, allowing it to pass through multiple deposition layers 120. The heating element 510 is generally a heating wire. Multiple heating elements 510 and multiple temperature sensors can be arranged inside the column 520 to heat or measure the temperature of different deposition layers 120. The control system is electrically connected to the heating elements 510 and temperature sensors of the column 520. The control system precisely adjusts the temperature of different deposition layers 120 according to the temperature gradient set by the system and acquires the temperature of different deposition layers 120 in real time. Multiple columns 520 are arranged inside the reaction chamber 110 to form a three-dimensional temperature monitoring network, which can monitor the temperature data at different depths and positions inside the reaction chamber 110 in real time. During the experiment, the control system dynamically adjusts the heating elements 510 of each temperature control module based on preset geothermal gradient parameters (which conform to the typical geothermal gradient characteristics of shallow deep seas, such as a temperature increase of 0.03-0.05℃ per meter of depth) and real-time data collected by temperature sensors. This ensures a stable temperature gradient within the reaction chamber 110 that conforms to geological laws. For example, the control system controls the heating element 510 located in the third sedimentary layer 123 to operate at a lower power, maintaining the temperature of the third sedimentary layer 123 within a lower range to simulate the low-temperature environment near the seabed surface. Along the direction from the top to the bottom of the reaction chamber 100, the operating power of the heating element 510 on the same column 520 gradually increases, thereby realizing the temperature gradient change within the reaction chamber 110 and providing precise temperature conditions for the formation and distribution of hydrates at different depths.

[0062] like Figure 1As shown, the simulation device also includes a monitoring component 600, which includes a monitoring sensor 610 disposed within the reaction chamber 110. The monitoring sensor 610 includes at least one of a fluid pressure sensor, a shear strength sensor, and a resistivity sensor. The fluid pressure sensor is used to convert the pressure applied by the fluid into a usable electrical signal, such as a piezoresistive pressure sensor. The shear strength sensor can be a shear force sensor, which measures the magnitude of the shear force on an object based on the principle that a material deforms under shear force, thereby determining the shear strength. The resistivity sensor is used to measure the resistivity of a material, such as an electrode conductivity sensor. The electrode conductivity sensor applies an alternating voltage to water through two or four electrodes, measures the current to calculate the conductivity, and then converts it into resistivity. In this embodiment, the monitoring sensor 610 includes a fluid pressure sensor, a shear strength sensor, and a resistivity sensor, enabling real-time and intelligent monitoring of the simulation parameters for the dynamic formation and evolution of hydrates.

[0063] In geological exploration, parameters such as resistivity, shear strength, and density are often used to determine the distribution characteristics of hydrates. In hydrate-free gas systems, the higher the hydrate saturation, the stronger the associated acoustic and electrical signals; while gas layers may have high resistivity, their shear strength and density signals are weaker. This invention utilizes a monitoring sensor 610 to achieve real-time monitoring of parameters such as resistivity and shear strength during the dynamic formation and evolution of hydrates. The resistivity sensor reflects the formation and decomposition state of hydrates through resistivity changes; the shear strength sensor records the intensity changes caused by hydrate cementation sediments; and the fluid pressure sensor monitors fluid migration and pressure changes due to phase changes during the dynamic evolution of hydrates. Through data acquisition and application control systems and supporting simulation software, the hydrate phase equilibrium equation can be accurately constructed, and the spatiotemporal evolution state of the simulated hydrate stability domain can be inverted in real time, enabling the interpretation of hydrate formation and decomposition behavior from a thermodynamic perspective. By monitoring macroscopic physical parameters to invert the hydrate state, data is provided for analyzing its impact on reservoir properties. The core component is a monitoring assembly 600 composed of multiple monitoring sensors 610. Each assembly integrates a resistivity sensor, a shear strength sensor, and a fluid pressure sensor, enabling the simultaneous acquisition of multiple parameters at the same location for correlation analysis. During the specific experiment, all sensors continuously collect data at a certain frequency and transmit it to the control system in real time, dynamically reflecting changes in reservoir properties. For example, during the hydrate formation stage, resistivity and shear strength increase synergistically with hydrate formation, and fluid pressure also changes accordingly, directly reflecting the changes in reservoir state.

[0064] like Figure 1As shown, in some embodiments, the detection assembly further includes a mounting column 620; the mounting column 620 is vertically disposed on the reaction chamber 100 and passes through multiple partitions 140; a monitoring sensor 610 is disposed on the mounting column 620; the mounting column 620 can support the monitoring sensor 610, so that the monitoring sensor 610 is stably disposed at a specific position within the reaction chamber 110, avoiding displacement of the monitoring sensor 610 due to airflow or other impacts; the monitoring sensor 610 can be disposed inside the mounting column 620, and the probe of the monitoring sensor 610 extends out of the mounting column 620, thus the mounting column 620 can protect the monitoring sensor 610 and reduce the influence of the internal environment of the reaction chamber 100 on the monitoring sensor 610. Multiple mounting columns 620 are provided to obtain parameters at different positions within the reaction chamber 110. It should be noted that at least one mounting column 620 is disposed inside the diapir simulator 200 to obtain parameters inside the diapir simulator 200. Similarly, at least one column 520 is disposed inside the diapir simulator 200.

[0065] like Figure 1 and Figure 8 As shown, in some embodiments, the evolution simulation device further includes a laser Raman detection component 700, which is disposed on one side of the reaction chamber 100. The laser Raman detection component 700 includes a laser emitter 710, a filter group 720, and a spectrometer 730. In specific experiments, the laser is transmitted through the filter group 720 to the reservoir to irradiate the hydrate. The Raman spectral signal formed by molecular scattering is transmitted back to the spectrometer 730. After analysis, the crystal form (such as 2917 of type I hydrate) can be identified. Characteristic peaks), and analyze the composition of the gas source (e.g., methane 2916). 2960 ethane Characteristic peaks are detected, and hydrate saturation is inverted through peak intensity. Molecular spectroscopy is used to analyze the microscopic characteristics of hydrates, revealing their evolution mechanisms and complementing traditional modules to provide microscopic explanations for macroscopic phenomena. For example, when the temperature field recedes, the decrease in reservoir temperature causes the bottom boundary of the hydrate stability domain to migrate downwards, resulting in a spatial shift in the location of the hydrate as the stability domain changes. At this time, the laser Raman detector 700 will detect characteristic peaks of the hydrate (such as 2917). The location of the peak changes with the migration of the storage space, and the peak intensity also changes accordingly due to the formation or enrichment state of the hydrate in the new stability region. This corroborates the macroscopic phenomena such as increased resistivity and intensity monitored by traditional modules, revealing the mechanism by which the temperature field decay affects the stability of hydrates from both macroscopic and microscopic perspectives. The laser Raman detection component 700 is a prior art device, and will not be described in detail in the embodiments of this invention.

[0066] By combining the monitoring component 600 and the laser Raman detector component 700 at different scales, a comprehensive integration of macroscopic physical parameters and microscopic evolution process information is achieved. Through the coordinated acquisition of macroscopic physical parameters and microscopic molecular characteristic parameters, the influence mechanism of temperature field decay on hydrates is comprehensively analyzed. This serves as a crucial bridge connecting experimental phenomena with scientific laws, providing all-round data support for the study of hydrate formation, decomposition, and evolution.

[0067] like Figure 1 As shown, in some embodiments, the reaction chamber 100 is provided with multiple cooling walls 130, which surround and form a reaction cavity 110 to improve the cooling efficiency of the reaction cavity 110; the cooling cavities of two adjacent cooling walls 130 are connected to facilitate the flow of coolant in different cooling walls 130, so that the temperature of multiple cooling walls 130 tends to be consistent.

[0068] like Figure 1 As shown, in some embodiments, the simulation device further includes a cooling assembly 800, which includes a drive pump 810, a storage container 820, an input pipe 830, an output pipe 840, and a cryogenic controller 850. The input pipe 830 connects the inlet end of the receiving cavity 131 of the cooling wall 130 to the outlet end of the storage container 820, and the output pipe 840 connects the outlet end of the receiving cavity 131 to the inlet end of the storage container 820. The drive pump 810 and the cryogenic controller 850 are disposed on the input pipe 830. The drive pump 810 is used to drive the coolant in the storage container 820 to be delivered to the receiving cavity 131 of the cooling wall 130, and then back to the storage container 820 from the receiving cavity 131. The cryogenic controller 850 is used to adjust the flow rate of the coolant in the input pipe 830 to adjust the temperature of the cooling wall.

[0069] Understandably, the storage container 820 is used to store low-temperature coolant. Driven by the drive pump 810, the low-temperature coolant in the storage container 820 enters the interior of the container 131 through the inlet pipe 830 and the inlet end of the container 131. The coolant absorbs heat to reduce the temperature of the cooling wall 130. The cooling wall 130 absorbs heat from the top of the reaction chamber 100 to simulate the formation temperature field of the hydrate-rich area under real geological conditions. Driven by the pump 810, the coolant from the cooling wall 130 flows back into the storage container 820 through the outlet end of the receiving cavity 131, the output pipe 840, and the inlet end of the storage container 820. The cryogenic controller 850 may include a temperature sensor and a flow meter. The temperature sensor is installed on the input pipe 830 or the output pipe 840 and is used to obtain the temperature of the fluid. The flow meter is installed on the input pipe 830 or the output pipe 840 and adjusts the flow rate of the fluid according to the temperature obtained by the temperature sensor. This embodiment of the invention also includes a refrigeration system, which is a refrigeration device in the prior art, including components such as an evaporator, a compressor, and a condenser. The evaporator is used to absorb heat from the storage container 820. It should be noted that since the cooling cavities of two adjacent cooling walls 130 are connected, the input pipe 830 and the output pipe 840 can be connected to the receiving cavity 131 of one of the cooling walls 130.

[0070] To simulate the constant low-temperature environment of deep-sea surrounding rocks, multiple cooling walls 130 are arranged around the reaction chamber 100. Each cooling wall 130 may include two layers of glass, forming a cavity 131 between them. The cooling walls 130 and the heating element 510 work together to maintain the temperature stability of the reservoir simulation system. Generally, the coolant can be an aqueous solution of ethylene glycol, which has good low-temperature fluidity and thermal conductivity to improve the cooling efficiency of the cooling walls 130.

[0071] Traditional hydrate simulation devices often focus on single factors such as hydrostatic pressure, deposition rate, and geothermal gradient. This application's simulation device, for the first time, uses the temperature field decay process as the core control variable. It constructs a complete system through multi-system collaboration, encompassing "environmental pressure - geological carrier - gas supply - process control - monitoring and analysis," to reproduce the dynamic evolution of hydrates driven by temperature field decay, specifically targeting the temperature field evolution scenario accompanying deep hydrothermal activity. This approach breaks through the traditional research direction dominated by pressure changes, opening up a new research dimension centered on the evolution of the stable domain controlled by the temperature field. Based on the indirect control technology of fluid rate-temperature coupling, the simulation device of this invention innovatively adopts an indirect control strategy of "fluid rate-heat transfer-temperature field evolution." Through fluid rate-temperature coupling control, under the premise of a constant initial gas temperature in the mixing pipe 310, the fluid injection rate is adjusted by the control valve 311 to change the convective heat transfer intensity, achieving accurate simulation from the high temperature of the hydrothermal activity period to natural decay, closely conforming to the real geological law that "the rate of hydrothermal activity dominates heat transfer." This invention overcomes the limitations of single-variable control, achieving dynamic coupling of "fluid activity rate - gas composition - temperature field evolution." The gas supply component 300 provides precisely proportioned gases such as methane and ethane, and the flow rate is controlled by the control valve 311 to simulate hydrate formation processes under different thermal fluid activity scenarios (e.g., high-rate flow carrying more thermogenic gases like ethane and propane; low-rate flow carrying more methane), thus improving the realism of geological simulations. This invention also overcomes the limitations of traditional single-physical parameter monitoring, constructing a multi-dimensional monitoring network of "traditional physical parameters + in-situ molecular spectroscopy." Resistivity, shear strength, and fluid pressure sensors macroscopically monitor the impact of hydrates on reservoir properties, while the laser Raman detection component 700 identifies hydrate crystal types (e.g., Type I 2917). Characteristic peaks), analysis of gas components (such as methane 2916) 2960 ethane Characteristic peaks) and inverse saturation are analyzed to achieve full-scale analysis of the influence mechanism of temperature field decay. Furthermore, this invention addresses the key geological process of deep gas-bearing fluid migration to shallower layers. The simulation device innovatively designs a mud dipivot simulator 200 with a "narrow bottom and wide top, mushroom-shaped composite structure." It guides gas flow through a guide channel 211 to simulate the vertical migration of deep fluids, and guides gas diffusion through a mushroom-shaped diffusion protrusion 213 at the top to simulate lateral diffusion after pressure release. The simulation pipe 240 simulates fractures in the reservoir, restoring the characteristics of real reservoir fractures. An embedded impedance sensor 260 monitors the gas-water ratio in real time, supporting fluid migration path analysis.

[0072] Compared with existing technologies, this invention demonstrates significant advantages in the realism of geological process simulation, the ability to coordinate and control multi-dimensional parameters, and the accuracy of full-scale monitoring. Existing hydrate simulation devices mostly focus on a single pressure or temperature variable, making it difficult to reproduce the dynamic coupling process of "thermal fluid activity - temperature field decay - hydrate evolution." Furthermore, they often simplify the geological carrier structure, failing to accurately simulate the fluid migration path dominated by muddicipient structures and the heterogeneous characteristics of reservoirs. Their ability to capture the migration of hydrate stability domains and microscopic molecular responses driven by temperature field decay is limited, thus restricting the in-depth analysis of hydrate accumulation mechanisms under complex geological conditions.

[0073] This invention addresses the exploration needs of hydrates in the context of deep-sea shallow hydrothermal activity. It innovatively constructs an integrated system encompassing "gas supply - rate-temperature coupled regulation - geological carrier simulation - multi-dimensional monitoring," achieving precise simulation of the entire process from the hydrothermal activity phase to the natural decline of the temperature field. The simulation device uses fluid rate regulation as its core link, linking multi-component gas source ratios with temperature and pressure environment control to realistically reproduce the geological logic chain of "rate change - heat transfer - temperature field evolution." Combined with a mushroom-shaped mud diapiric simulator 200 and a fracture network design, it accurately simulates the vertical transport and lateral diffusion characteristics of fluids. Through the coordinated monitoring of macroscopic physical parameters and in-situ Raman molecular detection, it achieves full-scale dynamic capture of reservoir physical parameter changes, down to microscopic hydrate crystal forms and saturation. Simultaneously, it supports flexible adjustment of parameters such as fluid rate and temperature control gradient, significantly improving adaptability to different hydrothermal activity intensities and tectonic backgrounds, providing an innovative experimental platform for revealing the formation, decomposition, and evolution mechanisms of hydrates driven by temperature field decline.

[0074] A second aspect of the present invention provides a method for simulating dynamic hydrate accumulation under a temperature field decline background, such as... Figures 1 to 8 As shown, the device for simulating dynamic hydrate accumulation under a temperature field decline background provided in the first aspect embodiment above includes:

[0075] Water with a sodium chloride content of 3.5% (by weight) is injected into reaction chamber 110;

[0076] Coolant is introduced into the receiving cavity 131 of the cooling wall 130;

[0077] Alkane gas is introduced into the guide channel 211 through the gas supply component 300.

[0078] By injecting water with a sodium chloride content of 3.5% (by weight) into the reaction chamber 110, a high-pressure environment is created within the reaction chamber 110, ensuring the stability of the pressure field during the experiment and providing a pressure boundary that conforms to real deep-sea conditions for the formation, decomposition, and temperature field evolution of hydrates. Coolant is introduced into the containment cavity 131 of the cooling wall 130 to reduce the temperature within the reaction chamber 110, thereby simulating deep-sea temperatures. Alkane gas is introduced into the guiding channel 211 through the gas supply component 300, causing the alkane gas to diffuse in the diffusion section 210 and spread in the diffusion region 220, thereby simulating the migration of deep gas-bearing fluids to shallow reservoirs under the background of temperature field decline, and thus simulating the formation and evolution process of hydrates under the background of temperature field decline.

[0079] By injecting water with a sodium chloride content of 3.5% (by weight) into reaction chamber 110, a high-pressure environment with a hydrostatic pressure of approximately 15 MPa or higher is created within the chamber, simulating the high-pressure conditions of deep-sea environments above 1500 meters. This provides a reliable experimental platform for research related to hydrate accumulation and evolution simulation. The reaction chamber 100 features a fully sealed structure, with pressure control ports on its top for injecting water into the device. To closely approximate the geochemical characteristics of fluids in a marine environment, the water contains 3.5% (35‰) sodium chloride, better matching the geochemical composition of seawater and pore water under real marine geological conditions. During operation, a high-precision hydraulic pump controls the water injection volume, thereby achieving precise control of the internal pressure of reaction chamber 110, ensuring a uniform high-pressure environment that remains stable above 15 MPa.

[0080] This application focuses on the dynamic formation and evolution of hydrates under the background of temperature field decline, with particular attention to the impact mechanism of natural temperature field decline caused by changes in the intensity of hydrothermal activity on the migration, occurrence state, and reservoir properties of hydrate stable domains. The simulation device, based on a modular and collaborative concept, constructs a multi-dimensional intelligent monitoring network that coordinates macroscopic physical parameters and microscopic molecular characteristics through an integrated system design of "precise gas supply—rate-temperature coupling—geological carrier simulation," enabling dynamic capture and quantitative characterization of the entire process of hydrate formation, decomposition, and evolution. This simulation device provides an effective experimental path for exploring the dynamic evolution of hydrates driven by temperature field decline, and is of great significance for revealing the occurrence laws and evolution mechanisms of hydrates under the background of hydrothermal curtain activities such as mud diapirs and gas chimneys. Currently, there are no relevant simulation devices or products in the field of hydrate research targeting "fluid rate-temperature field coupling regulation" and "full-scale monitoring of the impact of temperature field decline." Its innovative design provides a key experimental platform for the study of hydrate evolution under complex geological conditions.

[0081] This invention, for the first time, uses the temperature field as a core element, focusing on the dynamic evolution of hydrates under the background of temperature field decay. It takes the evolution of the stable domain controlled by the temperature field as a breakthrough point, providing a new perspective for revealing the temperature-driven mechanisms of hydrate formation and decomposition. Addressing the shortcomings of existing technologies, it proposes a new method for simulating temperature decay by indirectly controlling fluid activity rates. A coupled model of fluid transport and temperature field changes is established to precisely regulate the supply rate and path of thermal fluids, realistically reproducing the geothermal field decay process during multiple thermal fluid intermittent periods. Multi-parameter dynamic coupling control technology is employed to construct a collaborative control system including elements such as "gas source regulation, temperature field adjustment, and fluid pressure," achieving dynamic matching and linkage adjustment of multiple parameters under different geological scenarios, improving the realism of simulation experiments under complex geological conditions. Temperature sensors and heating elements 510 are set up to achieve real-time monitoring and dynamic feedback adjustment of the temperature field, precisely controlling the temperature gradient and local thermal anomalies. The microstructure and temperature field distribution of hydrates are monitored, and a quantitative correlation model of temperature-structure-properties is established through data fusion. Overall, this application achieves key breakthroughs in simulation concepts, temperature decay simulation methods, dynamic coupling control, and multi-dimensional detection systems. Compared with existing technologies, it has significant advantages in research depth, control accuracy, simulation realism, and data acquisition capabilities. It provides an efficient experimental platform for the study of hydrate evolution under the background of temperature field decay and also provides important technical support for hydrate resource exploration and geological risk assessment.

[0082] The embodiments of the present invention also include a high-definition touch screen and a physical keyboard, so as to input core parameters such as gas source composition (methane, ethane, etc.), fluid rate, initial reservoir temperature, geothermal gradient, environmental pressure and experimental duration, so as to control the simulation device to operate according to the set parameters.

[0083] The simulation device of this invention constructs a complete system of "environmental foundation - geological carrier - material supply - process control - monitoring and analysis," realizing the simulation of hydrate dynamic evolution driven by temperature field decay in a deep-sea environment at a depth of 1500 meters (above 15 MPa) under real geological conditions. From the construction of the pressure environment to the control of the temperature field, from the gas supply to the regulation of the fluid rate, from the monitoring of macroscopic physical parameters to the analysis of microscopic molecular characteristics, the entire process closely matches the real geological conditions of shallow deep-sea layers, providing a precise, controllable, and fully functional experimental platform for the study of hydrate accumulation mechanisms. The simulation device has a compact overall structure, is easy to operate, and has flexible and diverse parameter settings. It can be widely used in experimental research in multiple fields such as the evolution law of hydrate stability domains, the main controlling factors of accumulation, and development response, providing strong technical support for the exploration, development, and theoretical research of deep-sea natural gas hydrates.

[0084] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A device for simulating dynamic hydrate accumulation under a temperature field decline background, characterized in that, include: A reaction chamber has a reaction cavity, which is provided with multiple deposition layers arranged along the height direction of the reaction chamber; the deposition layers are filled with filler particles; at least one side wall of the reaction chamber is a cooling wall, and the cooling wall is provided with a receiving cavity for containing coolant; A mud diverter simulator includes a diffuser, a shell, and multiple simulation tubes; the diffuser is provided with a guide channel and an outlet communicating with the guide channel, the outlet being located at the top of the diffuser; the diffuser is located inside the reaction chamber, and a diffusion region is formed above the diffuser, the diffusion region being located within at least one of the deposition layers; the cross-sectional area of ​​the guide channel gradually increases along the direction from the bottom to the top of the reaction chamber; A gas supply assembly, connected to the guide channel, is used to supply alkane gases to the guide channel; The simulation tube is located within the guide channel and is connected to the gas supply assembly; along the direction from the bottom to the top of the muddipper simulator, the simulation tube bends from the middle of the guide channel toward the edge of the guide channel; the tube wall of the simulation tube is provided with a main crack, the main crack including multiple bends, the multiple bends are arranged along the extension direction of the simulation tube, and the extension directions of two adjacent bends are different; the tube wall of the simulation tube is provided with multiple branch cracks, the branch cracks are connected to the main crack; the outer shell is filled with filler particles; the outer shell is provided with an air inlet channel and an air inlet communicating with the air inlet channel, the guide channel is located inside the outer shell, and the guide channel is connected to the air inlet channel.

2. The hydrate dynamic accumulation simulation device under temperature field decline background according to claim 1, characterized in that, At least two of the aforementioned analog tubes are arranged alternately.

3. The hydrate dynamic accumulation simulation device under temperature field decline background according to any one of claims 1 to 2, characterized in that, The gas supply assembly includes a gas mixing pipe and multiple gas storage containers, which are used to hold different gases; the inlet end of the gas mixing pipe is connected to the multiple gas storage containers, and the outlet end of the gas mixing pipe is connected to the guide channel; multiple agitators are installed inside the gas mixing pipe, which are used to mix the gas inside the gas mixing pipe.

4. The hydrate dynamic accumulation simulation device under temperature field decline background according to any one of claims 1 to 2, characterized in that, The simulation device also includes multiple heating elements and multiple temperature sensors. The multiple heating elements are arranged in the reaction chamber along the height direction of the reaction chamber, and the multiple temperature sensors are arranged in the reaction chamber along the height direction of the reaction chamber. Each deposition layer is provided with at least one heating element and at least one temperature sensor.

5. The hydrate dynamic accumulation simulation device under temperature field decline background according to any one of claims 1 to 2, characterized in that, The reaction chamber is provided with multiple cooling walls, which together form the reaction cavity.

6. A method for simulating dynamic hydrate accumulation under a temperature field decline background, characterized in that, The apparatus for simulating dynamic hydrate accumulation under the temperature field decline background as described in any one of claims 1 to 5 includes: Water with a sodium chloride content of 3.5% (by weight) is injected into the reaction chamber; Coolant is introduced into the cavity containing the cooling wall; Alkane gas is introduced into the guide channel through a gas supply component.

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