Thermal stratification reservoir particulate matter sedimentation motion test simulation device and simulation method

Abstract

The invention provides a thermal stratification reservoir particulate matter settlement motion test simulation device and method, and the device comprises a design stage, a test preparation stage, a preparation stage, a particle size measurement stage, a settlement test stage, a data processing and analysis stage and a test result stage. According to the method, the resistance coefficient CD and the Reynolds number parameter are calculated, the response relation between the resistance coefficient CD and the Reynolds number parameter and the particle morphology index is analyzed, the particle settling velocity is corrected, the influences of the fluid viscosity, the particle shape, the temperature gradient, the measurement error and other factors are considered, and the test result is more accurate and reliable.

Description

Technical Field

[0001] The invention relates to the field of particle dynamics, and in particular to a thermal stratified reservoir particle settling motion test simulation device and a simulation method. Background Art

[0002] In a thermally stratified reservoir, particles settle from the upper high-temperature layer to the lower low-temperature layer under the action of gravity. Thermal stratification has a certain decelerating effect on particle sedimentation. The geometric shapes of the sedimentation particles in the reservoir are mostly disc-shaped, floc-shaped and other structural forms.

[0003] In a liquid, the sedimentation rate of particles is proportional to the square of the particle size and inversely proportional to the viscosity of the liquid. Specifically, large particles are subject to a stronger gravitational force due to their large volume and heavy mass, so they settle faster; while small particles are the opposite and settle slower. In addition, the viscosity of the liquid will also affect the sedimentation rate of the particles. The greater the viscosity, the greater the resistance the particles encounter when settling, and the slower the sedimentation rate.

[0004] In existing sedimentation tests on particles, it is usually assumed that the particles are ideal spheres. In fact, the shape of particles may be block, flake or other irregular shapes. The idealized assumption will lead to deviations between the actual sedimentation rate and the theoretical calculation results. In addition, the existing particle sedimentation dynamics test uses the test structure with the same temperature above and below, and only uses a single vertical temperature test, which limits the scope of application of the test. Researchers cannot fully explore the impact of vertical water temperature stratification on particle sedimentation behavior, and cannot simulate the particle sedimentation movement process under thermal stratification.

[0005] Therefore, it is necessary to provide a new particle sedimentation motion test device and method to solve the above technical problems. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a simulation device and method for the test of particle settling movement in a thermal stratified reservoir.

[0007] The thermal stratified reservoir particle settling motion test simulation device provided by the present invention comprises a test structure main body, the left and right sides of the test structure main body are provided with side plates, and the surfaces of the two side plates are provided with a plurality of monitoring holes for observing the particle settling motion trajectory.

[0008] Furthermore, a water tank is provided inside the main body of the test structure, and a temperature control plate 1 and a temperature control plate 2 for forming a temperature stratification interface are fixed to the bottom wall and the bottom wall of the water tank respectively. The main body of the test structure is rotatably arranged between the two side plates by a rotating column, and four relatively distributed slots 1 and two slots 2 are provided on the surfaces of the two side plates, and the two slots 2 are relatively located between the four slots 1. Four relatively grooves 1 and two relatively grooves 2 are provided on the front and back sides of the main body of the test structure, and a slide groove 1 is provided on the inner side walls of the four grooves 1, and a slide groove 2 is provided on the inner side walls of the two grooves 2, and the water tank is fixed to the bottom wall of the main body of the test structure, and the two ends of the temperature control plate 1 and the temperature control plate 2 are respectively fixed to the top wall and the bottom wall of the water tank, and a number of equidistantly distributed mounting holes are provided on the surfaces of the temperature control plate 1 and the temperature control plate 2.

[0009] Furthermore, the limiting mechanism includes a card plate 1 and a card plate 2, the number of card plates 1 and card plates 2 are eight and four respectively, the bottom of card plate 1 slides on the bottom wall of the groove 1, a pull ring 1 is fixed to the top of card plate 1, the bottom of card plate 2 slides on the bottom wall of the groove 2, a pull ring 2 is fixed to the top of card plate 2, both ends of card plate 1 slide on the bottom wall of the groove 1 through slide groove 1, and both ends of card plate 2 slide on the bottom wall of the groove 2 through slide groove 2, wherein when the two ends of card plate 2 slide on the bottom wall of the groove 2 through slide groove 2, no disturbance will be caused to the water tank.

[0010] The thermal stratified reservoir particle settling movement test simulation method provided by the present invention comprises the following steps:

[0011] S1. Test preparation stage: After the temperature stratification interface is formed, a sponge diffuser is used to slowly add the low-temperature constant temperature aqueous solution and the high-temperature constant temperature aqueous solution to the upper and lower sides of the temperature stratification interface in the water tank in sequence, and particles are prepared for testing;

[0012] S2, preparation stage: when preparing particles for testing, two groups of disc particles with different diameter-to-thickness ratios were prepared using acrylonitrile-butadiene-styrene, and agarose spheres were prepared by gelling agarose solution in deionized water to form porous particles;

[0013] S3, particle size measurement stage: the prepared disc particles and porous particles are measured for particle size using a microscope, and particles of the same type are selected and grouped;

[0014] S4, sedimentation test stage: after the grouping is completed, a single particle is released from the top of the water tank to the bottom of the water surface, and the particle is allowed to settle freely in the stratified water column. A camera with a macro lens is used to collect images, and the vertical water temperature distribution of each layer of each test water body and the sedimentation trajectory of the particles are observed and recorded. Multiple particles of the same type are used, and each particle is tested repeatedly for multiple times. At this time, the sedimentation trajectory of all types of particles and the particle direction data are collected;

[0015] S5, data processing and analysis stage: analyze and process the collected data of all types of particle settling trajectories and particle directions, perform image preprocessing on the particle trajectory, and quantitatively describe the particle settling behavior, and analyze the force process of particles in stratified water bodies, including gravity, buoyancy, drag and added mass force;

[0016] S6, test results stage: Based on the analyzed test data, calculate the resistance coefficient C D And Reynolds number parameters, analyze the particle resistance coefficient C under the action of water temperature stratification D As well as the response relationship between the Reynolds number parameters and the particle morphology indicators, the particle settling velocity is corrected.

[0017] Furthermore, in the test preparation stage, it also includes adding an aqueous solution of a certain water temperature into the water tank. The injection sequence of the sponge diffuser includes pouring the low-temperature aqueous solution into the bottom of the water tank first until the water level reaches the height of the lower temperature control plate 2. After the water tank is filled with the required volume of low-temperature water, the sponge diffuser is reused to inject the high-temperature aqueous solution into the water tank until the height of the water column reaches an appropriate height, and then a particle sedimentation test is carried out.

[0018] Furthermore, before using the sponge diffuser, it is necessary to soak the sponge diffuser in constant temperature water of a corresponding temperature to control the filling speed.

[0019] Furthermore, during the settlement test phase, temperature sensors need to be arranged at intervals of 0.050 m in the vertical direction to continuously record the water temperature at an interval of 3 seconds.

[0020] Furthermore, when acrylonitrile-butadiene-styrene is used to prepare disc particles, the density thereof is 1.050 g / mL. The disc particles include thin discs and thick discs. The required disc particles are selected according to the morphological characteristics of the particles monitored in situ in the reservoir. Agarose spheres are prepared by gelling agarose solution in deionized water to form porous particles. The dry density of agarose is 1.640 g / mL.

[0021] It should be noted that a plurality of particles of the same type were used, and each particle was subjected to multiple repeated tests. The multiple types included thin discs, thick discs, and porous particles, and each group was subjected to multiple repeated tests.

[0022] Compared with the related art, the thermal stratified reservoir particle settling motion test simulation device and simulation method provided by the present invention have the following beneficial effects:

[0023] 1. By simulating different temperature environments and particle shapes, the improved test structure and method can more realistically reflect the behavior of different types of particles in the actual sedimentation process, help reduce the deviation caused by the use of idealized particles, that is, ideal spheres, for testing, and improve the accuracy and reliability of the test results.

[0024] 2. Sedimentation tests of different types of particles in different sedimentation environments are used for analysis. The sedimentation velocity of the particles is corrected. This method takes into account the influence of factors such as fluid viscosity, particle shape, temperature gradient and measurement error, making the sedimentation velocity obtained by this method more accurate and reliable. The sedimentation velocity is adjusted to ensure the accuracy of the test results. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the overall structure of the test structure body in the present invention;

[0026] Figure 2 It is a schematic diagram of the main structure of the whole test structure in the present invention;

[0027] Figure 3 is a schematic diagram of the structure of the side panel;

[0028] Figure 4 It is a structural schematic diagram of the second card board;

[0029] Figure 5 It is a schematic cross-sectional structure diagram of the entire test structure body in the present invention;

[0030] Figure 6 It is a structural schematic diagram of the temperature control board 1;

[0031] Figure 7 is a schematic diagram of the sedimentation in the water tank;

[0032] Figure 8 Schematic diagram of the force acting on a single spherical particle;

[0033] Fig. 9 It is a flowchart of the overall operation process of the present invention.

[0034] Numbers in the figure: 1. Side panel; 11. Monitoring hole; 12. Rotating column; 13. Slot one; 14. Slot two; 2. Test structure body; 21. Groove one; 211. Slide one; 22. Groove two; 221. Slide two; 23. Card plate one; 231. Pull ring one; 24. Card plate two; 241. Pull ring two; 3. Water tank; 31. Temperature control board one; 32. Temperature control board two; 33. Installation hole; 4. Shooting area. DETAILED DESCRIPTION

[0035] The present invention will be further described below in conjunction with the accompanying drawings and implementation modes.

[0036] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0037] In the description of the present invention, it should be understood that the directions or positional relationships indicated by the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside" and "outside" are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0038] Embodiment 1

[0039] In the specific implementation process, Figures 1 to 9As shown, a thermal stratified reservoir particle settling motion test simulation device includes a test structure body 2, and side panels 1 are provided on the left and right sides of the test structure body 2. The surfaces of the two side panels 1 are provided with a plurality of monitoring holes 11 for observing the particle settling motion trajectory. The surface of the test structure body 2 is also provided with a limiting mechanism for limiting the position of the test structure body 2. Among them, the monitoring hole can be a hole-shaped structure or a strip-shaped window structure, which is mainly convenient for real-time image capture by camera. In addition, the cameras used to shoot and capture the particle movement position can be arranged in the X and Y directions of the test structure body 2 respectively, so as to capture the particle movement position at each moment in a two-dimensional plane, thereby improving the accuracy.

[0040] A water tank 3 is also provided inside the test structure main body 2. The bottom wall and the bottom wall of the water tank 3 are respectively fixed with a temperature control plate 1 31 and a temperature control plate 2 32 for forming a temperature stratification interface. The test structure main body 2 is rotatably arranged between the two side panels 1 through a rotating column 12. Four relatively distributed slots 13 and two slots 2 14 are also provided on the surfaces of the two side panels 1. The two slots 2 14 are relatively located between the four slots 13. Four relatively grooves 1 21 and two relatively grooves 22 are provided on the front and rear sides of the test structure main body 2. A slide groove 1 211 is provided on the inner side walls of the four grooves 1 21. A slide groove 221 is provided on the inner side walls of the two grooves 22. The water tank 3 is fixed to the bottom wall of the test structure main body 2. The two ends of the temperature control plate 1 31 and the temperature control plate 2 32 are respectively fixed on the top wall and the bottom wall of the water tank 3. A number of equidistantly distributed mounting holes 33 are also provided on the surfaces of the temperature control plate 1 31 and the temperature control plate 2 32.

[0041] The limiting mechanism includes a card plate 1 23 and a card plate 24. The number of the card plates 1 23 and the number of the card plates 24 are eight and four respectively. The bottom of the card plate 1 23 slides on the bottom wall of the groove 1 21. The top of the card plate 1 23 is fixed with a pull ring 1 231. The bottom of the card plate 24 slides on the bottom wall of the groove 22. The top of the card plate 24 is fixed with a pull ring 241. The two ends of the card plate 1 23 slide on the bottom wall of the groove 1 21 through the slide groove 1 211. The two ends of the card plate 24 slide on the bottom wall of the groove 22 through the slide groove 221.

[0042] When the test structure body 2 slides to the limit mechanism, one end of the clamping plate 1 23 and the clamping plate 2 24 are respectively inserted into the slot 1 13 and the slot 2 14 , and the positioning is reliable, so no disturbance is caused to the water tank 3 .

[0043] A method for simulating the settling movement of particles in a thermally stratified reservoir comprises the following steps:

[0044] S1, test preparation stage: after the temperature stratification interface is formed, a sponge diffuser is used to slowly add the low-temperature constant temperature aqueous solution and the high-temperature constant temperature aqueous solution to the upper and lower sides of the temperature stratification interface in the water tank 3 in sequence, and particles are prepared for testing;

[0045] During the test preparation stage, it also includes adding an aqueous solution of a certain water temperature into the water tank 3. The injection sequence of the sponge diffuser includes pouring the low-temperature aqueous solution into the bottom of the water tank 3 first until the water level reaches the height of the lower temperature control plate 2 32. After the water tank 3 is filled with the required volume of low-temperature water, the sponge diffuser is used again to inject the high-temperature aqueous solution into the water tank 3 until the height of the water column reaches an appropriate height. At this time, a particle sedimentation test is carried out.

[0046] In addition, before using the sponge diffuser, it is necessary to soak the sponge diffuser in constant temperature water of a corresponding temperature to control the filling speed.

[0047] S2, preparation stage: when preparing particles for testing, two groups of disc particles with different diameter-to-thickness ratios were prepared using acrylonitrile-butadiene-styrene (ABS), and agarose spheres were prepared by gelling agarose solution in deionized water to form porous particles;

[0048] When acrylonitrile-butadiene-styrene (ABS) is used to prepare disc particles, the density thereof is 1.050 g / mL. The disc particles include thin discs and thick discs. The required disc particles are selected according to the morphological characteristics of the particles monitored in situ in the reservoir. Agarose spheres are prepared by gelling agarose solution in deionized water to form porous particles. The dry density of agarose is 1.640 g / mL.

[0049] S3, particle size measurement stage: the prepared disc particles and porous particles are measured for particle size using a microscope, and particles of the same type are selected and grouped;

[0050] S4, sedimentation test stage: after the grouping is completed, a single particle is released under the water surface at the top of the water tank 3 to allow the particle to settle freely in the stratified water column. A camera with a macro lens is used to collect images, and the vertical water temperature distribution of each layer of each test water body and the sedimentation trajectory of the particles are observed and recorded. Multiple particles of the same type are used, and each particle is tested repeatedly for multiple times. At this time, the sedimentation trajectory of all types of particles and the particle direction data are collected;

[0051] During the settlement test phase, temperature sensors need to be arranged vertically every 0.050m to continuously record the water temperature with a recording interval of 3s.

[0052] S5, data processing and analysis stage: analyze and process the data of all types of particle settling trajectories and particle directions after collection, perform image preprocessing on the particle trajectory, and quantitatively describe the particle settling behavior, and analyze the force process of particles in stratified water bodies, including gravity, buoyancy, drag and added mass force;

[0053] S6, test results stage: Based on the analyzed test data, calculate the resistance coefficient C D And Reynolds number parameters, analyze the particle resistance coefficient C under the action of water temperature stratification D As well as the response relationship between the Reynolds number parameters and the particle morphology indicators, the particle settling velocity is corrected.

[0054] It should be noted that the height of the test structure main body 2 is 2.0m, the length and width of the test structure main body 2 are 0.09m, and the temperature control plate 1 31 and the temperature control plate 2 32 are respectively fixed on the horizontal planes 0.020m and 1.180m away from the bottom of the water tank 3;

[0055] It should be noted that the monitoring holes 11 provided on the side panels 1 allow researchers to observe the sedimentation trajectory of particles, thereby obtaining accurate data, wherein the side panels 1, the test structure body 2 and the water tank 3 are all made of transparent materials.

[0056] It should be noted that the limiting mechanism includes a card plate 1 23 and a card plate 24. When in use, the pull ring 1 231 and the pull ring 241 are pulled to slide in the groove 1 21 and the groove 2 22, and the position is fixed by the slide groove 1 2111 and the slide groove 221.

[0057] It should be noted that in the test preparation stage, in order to determine the vertical change of the temperature in the water tank 3, it is necessary to arrange temperature sensors at intervals of 0.050m in the vertical direction to continuously record the water temperature. The recording time interval is 3s. Among them, the relationship between water temperature and density is nonlinear. The formula used for pure water temperature and density is as follows:

[0058] ρ T =a0+a1T+a2T 2 +a3T 3 +a4T 4 +a5T 5

[0059] Where T is the water temperature in °C; ρ T is the density of pure water, in kg / m3; a0, a1, a2, a3, a4, a5 are constants.

[0060] It should be noted that the disc particles are made of acrylonitrile-butadiene-styrene with a density of 1.050 g / mL. In the preparation of particles, an ABS acetone solution was prepared, and the droplets formed by the solution were dropped onto a polished glass plate. After the acetone evaporated, a thin sheet was formed. According to the morphological characteristics of the in-situ monitoring particles of the reservoir, two groups of disc particles with different diameter-thickness ratios were selected, namely thin discs and thick discs for testing;

[0061] The porous particles are made of agarose spheres, which are prepared by gelation of agarose solution in deionized water, with a dry density of 1.640 g / mL. During the gelation of the agarose solution, the agarose forms a fibrous microstructure with a porosity of about 95%.

[0062] It should be noted that the density of the particles was estimated by measuring the sedimentation velocity of the particles in distilled water at a constant temperature of 20°C. After measuring the particle size, the individual particles were gently transferred to the main body of the sedimentation behavior test structure through a pipette with a cut-off tip. The particle sedimentation velocity was calculated from the recorded vertical displacement, and the average sedimentation velocity was calculated over at least 3 consecutive seconds to obtain the sedimentation velocity u after the particles settled at a uniform speed, which was used to estimate the particle density ρ. a , the specific formula is:

[0063]

[0064] Where g is the acceleration due to gravity, ρ T is the water density, C D is the resistance coefficient, d is the particle diameter. Resistance coefficient C D The calculation of resistance is based on the following empirical law:

[0065]

[0066] It should be noted that the calculation formula of porosity is as follows:

[0067]

[0068] Where W is the particle mass and V is the particle volume. In the experiment, the mass of all porous particles was weighed, and the particle volume was obtained by summing the volumes of individual particles under a microscope.

[0069] It should be further explained that for particle density calculation, the following formula can also be used to calculate the particle density ρ a :

[0070]

[0071] Where, u is the settling velocity of the particle in mm / s;

[0072] g is the acceleration due to gravity 980 mm / s 2 ;

[0073] ρ T is the density of water 1g / cm 3 =1000kg / m 3 ;

[0074] C D is the drag coefficient;

[0075] d is the particle diameter in mm;

[0076] μ is the dynamic viscosity of water 1mPa·s=1cP=0.001Pa·s

[0077] For C D The drag coefficient can also be calculated using the following formula:

[0078]

[0079] Where Re is the Reynolds number, calculated as:

[0080]

[0081] For the calculation of the morphological index χ, the following formula can also be used:

[0082]

[0083] Where d is the particle diameter in mm;

[0084] t is the particle thickness in mm

[0085] For the calculation of porosity φ, the following calculation formula can also be used:

[0086]

[0087] Among them, ρ a is the density of the particle in g / mL;

[0088] ρ s is the density of the granular material in g / mL.

[0089] It should be noted that the particle settling test was carried out in the main body of the above-mentioned test structure, and two cameras (Basler acA2500-60um) equipped with Componon 2.8 / 28-001 (Schneider-Kreuznach) macro lenses were used for image acquisition, and 1 pixel of the camera corresponds to 31μm.

[0090] In all the tests of Example 1, the bottom layer temperature was kept constant, and the upper layer temperature was set based on monitoring experience, so that the surface and bottom temperature differences were ΔT, 2ΔT, and 3ΔT, respectively.

[0091] It should be noted that the sedimentation state of particles can also be analyzed as follows. First, the sedimentation state of particles is mainly determined by the force on the particles. First, it is necessary to analyze the force process of particles in stratified water. Particles that settle freely in still water are simultaneously affected by gravity (Fg), buoyancy (Ff), drag (Fd) and additional mass force (Fm).

[0092] Studies on spherical particles show that the gravity and buoyancy forces on the particles are as follows:

[0093]

[0094] Where z is the vertical coordinate, ρ T (z) is the density of the water at depth z.

[0095] When spherical particles settle in stratified water, the tail of the particle "entrains" the upper water, such as Figure 8 As shown, the volume of water attached to the tail of the particle is VL, and the gravity, buoyancy and resistance of the spherical particle change, specifically:

[0096]

[0097] In the formula, ρ T (z0) represents the density of water where the particle density is lower in the upper layer.

[0098] The resistance to particle settling is not only related to the Reynolds number of the particle, but also to the water temperature, particle shape (projected area), etc. The resistance calculation formula obtained from the spherical particle settling test is:

[0099]

[0100] Where u(z) is the settling velocity of the particle at depth z.

[0101] When particles settle in water, they push the surrounding water. Due to the inertial water body, the particles will show a reaction force and generate additional mass force, that is, the additional mass force increased by the acceleration or deceleration of the sedimentation in the static water body. The calculation formula of the additional mass force is:

[0102]

[0103] In the formula, the coefficient k is related to the particle shape, and the value of spherical particles is 0.5;

[0104] Therefore, when the particle acceleration is not large, the added mass force can be ignored.

[0105] Analysis of the sedimentation of spherical particles in still water:

[0106] It can be roughly divided into two stages, namely the acceleration stage and the stable stage. The resistance of the particle sedimentation is proportional to the square of the sedimentation velocity u(z). When the particle sedimentation velocity increases to a certain extent, the particle gravity, buoyancy and resistance reach a force balance, and the particle sedimentation velocity tends to be stable. At this time, the calculation formula of the particle sedimentation velocity is:

[0107]

[0108] According to the resistance calculation formula during particle sedimentation:

[0109] F d =3πduν (12)

[0110] The particle settling velocity can be expressed as:

[0111]

[0112] Where Re is the Reynolds number; ν is the kinematic viscosity of water, which is 1.05×10-2cm2 / s at 20°C.

[0113] It should be noted that the turning of disc particles and the "diffusion limit" behavior of porous particles during the sedimentation process significantly affect the particle sedimentation velocity. Therefore, the calculation formula for the sedimentation velocity of spherical particles mentioned above is corrected.

[0114] It should be further explained that the influence of particle morphology indicators such as particle size, shape, porosity, etc. on the sedimentation velocity is taken into account, the sedimentation velocity is obtained through experiments, and the resistance coefficient C is calculated. D , Reynolds number and other parameters, analyze the response relationship between these parameters and particle morphology indicators, refer to the classic formula of particle sedimentation velocity, use experimental data to correct the particle size, volume, porosity and other morphology index parameters in the formula, and obtain the velocity formula for different particle sedimentation.

[0115] References Figure 8 As shown, the field of view captured by the camera is located within the capturing area 4 .

[0116] The working principle provided by the present invention is as follows: The present invention can more realistically reflect the behavior of different types of particles in the actual sedimentation process, by adjusting the position of the temperature stratification interface and the shape of the particles, and conducting experiments, and calculating the resistance coefficient C according to the analyzed test data. D And Reynolds number parameters, analyze the particle resistance coefficient C under the action of water temperature stratification D As well as the response relationship between the Reynolds number parameters and the particle morphology indicators, the sedimentation velocity of the particles can be corrected.

[0117] The circuits and controls involved in the present invention are all prior art and will not be described in detail here.

[0118] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended to include all changes within the meaning and scope of the equivalent elements of the claims, and any figure mark in the claims should not be regarded as limiting the claims involved.

[0119] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A thermal stratified reservoir particle settling movement test simulation device, characterized in that: The invention comprises a test structure body (2), wherein the left and right sides of the test structure body (2) are both provided with side panels (1), the surfaces of the two side panels (1) are both provided with a plurality of monitoring windows (11) for observing the particle settling movement trajectory, and the surface of the test structure body (2) is also provided with a limit mechanism for limiting the position of the test structure body (2).

2. The thermal stratified reservoir particle settling movement test simulation device according to claim 1 is characterized in that: A water tank (3) is also provided inside the test structure body (2), and a temperature control plate 1 (31) and a temperature control plate 2 (32) for forming a temperature stratification interface are fixed to the bottom top and bottom wall of the water tank (3), respectively. The test structure body (2) is arranged between the two side plates (1) through a rotating column (12), and the surfaces of the two side plates (1) are also provided with four relatively distributed slots 1 (13) and two slots 2 (14), and the two slots 2 (14) are relatively located between the four slots 1 (13); The front and rear sides of the test structure body (2) are each provided with four opposite grooves 1 (21) and two opposite grooves 2 (22); the inner side walls of the four grooves 1 (21) are each provided with a slide groove 1 (211); the inner side walls of the two grooves 2 (22) are each provided with a slide groove 2 (221); the water tank (3) is fixed to the bottom wall of the test structure body (2); the two ends of the temperature control plate 1 (31) and the temperature control plate 2 (32) are respectively fixed to the top wall and the bottom wall of the water tank (3); and the surfaces of the temperature control plate 1 (31) and the temperature control plate 2 (32) are also provided with a plurality of equally spaced mounting holes (33).

3. The thermal stratified reservoir particle settling motion test simulation device according to claim 2 is characterized in that: The limiting mechanism comprises a card plate 1 (23) and a card plate 2 (24), the number of the card plate 1 (23) and the number of the card plate 2 (24) are eight and four respectively, the bottom of the card plate 1 (23) slides on the bottom wall of the groove 1 (21), the top of the card plate 1 (23) is fixed with a pull ring 1 (231), the bottom of the card plate 2 (24) slides on the bottom wall of the groove 2 (22), the top of the card plate 2 (24) is fixed with a pull ring 2 (241), the two ends of the card plate 1 (23) slide on the bottom wall of the groove 1 (21) through the slide groove 1 (211), and the two ends of the card plate 2 (24) slide on the bottom wall of the groove 2 (22) through the slide groove 2 (221).

4. A method for simulating the settling movement of particles in a thermally stratified reservoir, characterized in that: The test simulation device according to any one of claims 1 to 3 is used to carry out the test, comprising the following steps: S1, test preparation stage: after the temperature stratification interface is formed, a sponge diffuser is used to slowly add the low-temperature constant temperature aqueous solution and the high-temperature constant temperature aqueous solution to the upper and lower sides of the temperature stratification interface in the water tank (3) in sequence, and particles are prepared for testing; S2, preparation stage: when preparing particles for testing, two groups of disc particles with different diameter-to-thickness ratios were prepared using acrylonitrile-butadiene-styrene, and agarose spheres were prepared by gelling agarose solution in deionized water to form porous particles; S3, particle size measurement stage: the prepared disc particles and porous particles are measured for particle size using a microscope, and particles of the same type are selected and grouped; S4, sedimentation test stage: after the grouping is completed, a single particle is released below the water surface at the top of the water tank (3) to allow the particle to settle freely in the stratified water column. A camera with a macro lens is used to collect images, and the vertical temperature distribution of each layer of each test water body and the sedimentation trajectory of the particles are observed and recorded. Multiple particles of the same type are used, and each particle is tested repeatedly for multiple times. At this time, the sedimentation trajectory of all types of particles and the particle direction data are collected; S5, data processing and analysis stage: analyze and process the collected data of all types of particle settling trajectories and particle directions, perform image preprocessing on the particle trajectory, and quantitatively describe the particle settling behavior, and analyze the force process of particles in stratified water bodies, including gravity, buoyancy, drag and added mass force; S6, test results stage: Based on the analyzed test data, calculate the resistance coefficient C D And Reynolds number parameters, analyze the particle resistance coefficient C under the action of water temperature stratification D As well as the response relationship between the Reynolds number parameters and the particle morphology indicators, the particle settling velocity is corrected.

5. The method for simulating the settling movement of particles in a thermally stratified reservoir according to claim 4, characterized in that: During the test preparation stage, it also includes adding an aqueous solution of a certain water temperature into the water tank (3). The injection sequence of the sponge diffuser includes first pouring the low-temperature aqueous solution into the bottom of the water tank (3) until the water level reaches the height of the lower temperature control plate 2 (32). After the water tank (3) is filled with the required volume of low-temperature water, the sponge diffuser is used again to inject the high-temperature aqueous solution into the water tank (3) until the height of the water column reaches an appropriate height, at which time a particle sedimentation test is carried out.

6. The method for simulating the settling movement of particles in a thermally stratified reservoir according to claim 4, characterized in that: Before using the sponge diffuser, it is necessary to soak the sponge diffuser in constant temperature water of a corresponding temperature to control the filling speed.

7. The method for simulating the settling movement of particles in a thermally stratified reservoir according to claim 4, characterized in that: During the settlement test phase, temperature sensors need to be arranged vertically every 0.050m to continuously record the water temperature with a recording interval of 3s.

8. The method for simulating the settling movement of particles in a thermally stratified reservoir according to claim 4, characterized in that: When acrylonitrile-butadiene-styrene is used to prepare disc particles, the density thereof is 1.050 g / mL. The disc particles include thin discs and thick discs. The required disc particles are selected according to the morphological characteristics of the particles monitored in situ in the reservoir. Agarose solution is gelled in deionized water to prepare agarose spheres to form porous particles. The dry density of agarose is 1.640 g / mL.

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