A multi-shaft differential stirring structure optimization method applied to adhesive production

Abstract

The application discloses a multi-shaft differential stirring structure optimization method applied to adhesive production, relates to the optimization technical field of a stirring reactor of high-viscosity materials, and comprises a multi-shaft differential stirring kettle which is composed of an eccentric tooth-shaped dispersion shaft and an axial single-paddle shaft, wherein the impellers of the eccentric shaft and the axial single-paddle shaft adopt tooth-shaped disc-type impellers and axial flow single-leaf paddle impellers respectively; the multi-shaft differential stirring kettle is applied to high-viscosity fluids with different filler ratios, the eccentric tooth-shaped dispersion shaft serves as a main shaft, the axial single-paddle shaft serves as an auxiliary shaft, and the speed ratio of the main shaft to the auxiliary shaft is set to be between 1 and 3. Therefore, the multi-shaft differential stirring structure optimization method applied to adhesive production has the advantages that the material mixing effect is enhanced, the mixing time is effectively shortened, a lower unit volume power consumption is maintained, the optimization design of a high-viscosity fluid and an adhesive synthesis reactor is provided with reference, and the industrial production efficiency and product quality are improved.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of optimization of agitated reactors for high viscosity materials, in particular to a multi-shaft differential stirring structure optimization method applied to adhesive production. BACKGROUND

[0002] As a key functional material, adhesives are widely used in modern industry, covering multiple fields such as construction, automobiles, electronics, aerospace and biomedicine. With the increasing demand for high-performance adhesives, multiple components such as nanofillers, toughening agents and conductive particles are commonly introduced into their formulations, which puts higher requirements on the dispersion uniformity in the reactor. Studies have shown that the local dispersion state of fillers in the adhesive matrix directly affects the interfacial bonding strength, thermal stability and electrical conductivity of key properties. As the core device of the synthesis process, the structural design of the agitated reactor has a decisive influence on the dispersion effect.

[0003] Currently, for agitated reactors of high viscosity materials, researchers have proposed many improvement measures and optimization methods. These optimization methods mainly achieve this by changing the shape of the impeller, stirring rate, reactor shape and spatiotemporal combination of impellers. The serrated dispersion disc is of interest due to its superior radial local shear capacity and turbulence intensity compared to other impellers of the same size (Rushton impeller, anchor impeller, etc.). It also exhibits good mixing performance when dealing with high-concentration solid suspensions and poorly soluble substances, but it also has problems such as a single flow direction of the generated flow field and easy deposition at the bottom. Meanwhile, introducing axial impellers has become an important direction to address the mixing challenges of high viscosity systems. However, due to the uneven mixing of high viscosity materials at different positions, and the need to consider power consumption in actual application processes, etc.

[0004] Therefore, there is an urgent need for an optimization design method for high viscosity fluid and adhesive synthesis reactors that can comprehensively consider the unit volume power consumption of the stirring device and the mixing time under different impeller rotation speeds, providing a reference for the optimization of high viscosity material agitated reactors. SUMMARY

[0005] The purpose of the present application is to provide a multi-shaft differential stirring structure optimization method applied to adhesive production, which effectively improves the mixing degree of high viscosity material systems through the differential combination of different impellers, while maintaining low power consumption, and is suitable for high viscosity fluids of different fillers.

[0006] To achieve the above purpose, the present application provides a multi-shaft differential stirring structure optimization method applied to adhesive production, comprising:

[0007] The multi-shaft differential speed stirring vessel consists of an eccentric toothed dispersion shaft and an axial single impeller shaft, wherein the impellers of the eccentric toothed dispersion shaft and the axial single impeller shaft are respectively toothed disc impellers and axial flow single-blade impellers.

[0008] The multi-shaft differential speed stirring vessel is used for high-viscosity fluids with different packing ratios. The eccentric toothed dispersion shaft is used as the main shaft, and the axial single impeller shaft is used as the auxiliary shaft. The speed ratio between the main shaft and the auxiliary shaft is set between 1 and 3.

[0009] Preferably, the positions of the eccentric toothed dispersion shaft and the axial single impeller shaft are determined comprehensively based on velocity distribution, flow trajectory, mixing time, and power consumption per unit volume in the multi-axis differential stirring vessel.

[0010] Preferably, the axial single propeller shaft is located at the distal end of the eccentric toothed dispersion shaft, and a single axial single propeller shaft is selected to enhance the mixing effect while maintaining low power consumption per unit volume.

[0011] Preferably, when a multi-shaft differential speed stirred tank is used for high-viscosity fluids, a strategy of using a high-speed eccentric toothed dispersion shaft and a low-speed axial single impeller shaft is adopted.

[0012] Preferably, in the packing ratio In a 30% high-viscosity fluid, a high rotational speed ratio is selected for material mixing, with the main shaft: auxiliary shaft ratio set to 3:1.

[0013] Therefore, the present invention employs the above-mentioned method for optimizing a multi-axis differential stirring structure applied to adhesive production, and has the following technical effects:

[0014] This invention introduces an eccentric impeller and a differential axial single impeller shaft, which significantly breaks the symmetrical flow field, reduces the chaotic isolation zone, and enhances the axial flow of materials and overall chaotic mixing, thereby effectively shortening the mixing time. At the same time, considering both mixing time and power consumption, the invention adopts a stirring device with a single differential axial single impeller shaft, which ensures mixing efficiency while also offering energy-saving advantages.

[0015] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of different stirring reactors in an embodiment of a multi-axis differential stirring structure optimization method applied to adhesive production, wherein (a) is a single-serrated shaft stirring vessel, (b) is an eccentric single-serrated shaft stirring vessel, (c) is a uniaxial single-blade impeller-single-serrated biaxial stirring vessel, (d) is a biaxial single-blade impeller-single-serrated triaxial stirring vessel, (e) is a toothed disc impeller, and (f) is an axial flow single-blade impeller.

[0017] Figure 2This is an example of a method for optimizing the structure of a multi-axis differential stirring reactor used in adhesive production, showing the injection point and observation point of a liquid tracer in the stirred reactor, wherein (a) is a single-serrated shaft stirred reactor, (b) is an eccentric single-serrated shaft stirred reactor, (c) is a uniaxial single-blade impeller-single-serrated biaxial stirred reactor, and (d) is a biaxial single-blade impeller-single-serrated triaxial stirred reactor.

[0018] Figure 3 This is a three-dimensional streamline diagram of different stirred reactors in an embodiment of a multi-axis differential stirring structure optimization method applied to adhesive production, wherein (a) is a single serrated shaft stirred reactor, (b) is an eccentric single serrated shaft stirred reactor, (c) is a uniaxial single-blade impeller-single serrated biaxial stirred reactor, and (d) is a biaxial single-blade impeller-single serrated triaxial stirred reactor.

[0019] Figure 4 This is an example of a method for optimizing the structure of a multi-axis differential stirring reactor used in adhesive production. The YZ velocity vectors of different stirring reactors are shown in the example, where (a) is a single-sawtooth shaft stirring reactor, (b) is an eccentric single-sawtooth shaft stirring reactor, (c) is a uniaxial single-blade impeller-single-sawtooth biaxial stirring reactor, and (d) is a biaxial single-blade impeller-single-sawtooth triaxial stirring reactor.

[0020] Figure 5 This is an example of a method for optimizing a multi-axis differential stirring structure used in adhesive production, which includes the grouping and value positions of velocity distribution, where (a) is a single-axis group and (b) is a multi-axis group.

[0021] Figure 6 This is an example of a method for optimizing a multi-axis differential stirring structure applied to adhesive production. Examples show the normalized concentration of liquid tracers and their mixing time over time in different stirred reactors. (a) represents the normalized concentration of SSDM liquid tracers over time; (b) represents the normalized concentration of ESSDM liquid tracers over time; (c) represents the normalized concentration of ESDM-SAS liquid tracers over time; (d) represents the normalized concentration of ESDM-DSAS liquid tracers over time; and (e) shows the variation of mixing time with rotational speed.

[0022] Figure 7 This is an example of a method for optimizing a multi-axis differential speed stirring structure applied to adhesive production. The examples show the power consumption per unit volume and the corresponding mixing time of each stirring reactor at different stirring speeds. (a) represents the power consumption per unit volume P at different stirring speeds N. v (b) represents the mixing time t as a function of power consumption P per unit volume. v Changes;

[0023] Figure 8This is an example of a method for optimizing a multi-axis differential speed stirring structure applied to adhesive production. The examples show the packing dispersion and mixing of different packing ratios when the speed ratio is 3:1, where (a) is a 10% packing ratio, (b) is a 20% packing ratio, (c) is a 30% packing ratio, and (d) is a 40% packing ratio.

[0024] Figure 9 This is an example of a method for optimizing a multi-axis differential speed stirring structure applied to adhesive production. The examples show the packing dispersion and mixing of different packing ratios when the speed ratio is 2:1, where (a) is a 10% packing ratio, (b) is a 20% packing ratio, (c) is a 30% packing ratio, and (d) is a 40% packing ratio.

[0025] Figure 10 This is an example of a method for optimizing a multi-axis differential stirring structure applied to adhesive production. The examples show the packing dispersion and mixing of different packing ratios when the speed ratio is 1:1, where (a) is a 10% packing ratio, (b) is a 20% packing ratio, (c) is a 30% packing ratio, and (d) is a 40% packing ratio.

[0026] Figure 11 This is an example of a method for optimizing a multi-axis differential stirring structure used in adhesive production, which measures the mixing time of different filler ratios at different speed ratios. Detailed Implementation

[0027] The present invention will be explained in more detail through the following embodiments. The purpose of disclosing the present invention is to protect all changes and modifications within the scope of the present invention. The present invention is not limited to the following embodiments.

[0028] Example 1

[0029] This invention provides a method for optimizing a multi-axis differential speed stirring structure for adhesive production, including an axial flow single-blade impeller and a toothed disc impeller, with specific dimensions as shown below. Figure 1 As shown in Table 1.

[0030] This embodiment uses numerical simulation to set up different spatial combinations of axial flow single-blade impellers and toothed disc impellers, constructing four types of stirred reactors: a single-serrated shaft stirred reactor, an eccentric single-serrated shaft stirred reactor, a uniaxial single-blade impeller-single-serrated biaxial stirred reactor, and a biaxial single-blade impeller-single-serrated triaxial stirred reactor. These reactors are then applied to the analysis of the stirred flow field of a high-viscosity material—epoxy resin. During the numerical simulation, to reduce the influence of the flow dead zones at the top and bottom corners, the upper and lower walls of the stirred reactor were ellipticalized by 30mm.

[0031] Table 1. Specific dimensions of the stirred tank and impeller

[0032] ;

[0033] The flow of fluid materials inside the agitator is governed by the laws of conservation of mass, momentum, and energy, and its basic governing equations are shown below:

[0034] mass conservation equation:

[0035] ;

[0036] Momentum conservation equation:

[0037] ;

[0038] ;

[0039] ;

[0040] Energy conservation equation:

[0041] ;

[0042] in, It is a velocity vector. , and These are the velocity components in the tangential, radial, and axial directions, respectively. , They are respectively ( , or Gravitational body force and external body force in the direction of ) and These represent the mass source term and the energy source term, respectively. It is density ( ), It is static pressure (Pa). It is dynamic viscosity , It's temperature. It is time. It is the thermal conductivity. It is specific heat capacity.

[0043] In the simulation process of this embodiment, the medium material is set as epoxy resin, and its material parameters are shown in Table 2 below.

[0044] Table 2 Material Parameters

[0045] ;

[0046] The power consumption per unit volume is mainly obtained in simulation experiments. After the simulated system stabilizes, the torque value M is obtained, and then the power consumption can be calculated using the following formula:

[0047] ;

[0048] ;

[0049] In the formula, For the first Power consumption of each impeller; The volume inside the stirred tank is expressed in cubic meters (m³). 3 ; The value corresponds to the impeller torque, in N·m. This represents the corresponding impeller speed, in r / s.

[0050] Mixing time is an important indicator in the adhesive industry because it reflects the time required to complete the mixing process. Figure 3 The feed point (P0) and six monitoring points (P1-P6) of the liquid tracer are shown. Numerical simulation is used to track the dispersion of the tracer to estimate the mixing time, which is determined according to the 95% rule.

[0051] To investigate the flow behavior of high-viscosity adhesives within a reactor under different stirring modes, the Multi-Reference Frame (MRF) method was employed, treating the region containing the blades as the rotating dynamic domain and other regions as the static domain. In this embodiment, the stirring tank wall was designated as the static wall, while the stirring shaft and its impeller were designated as the moving wall. Ansys Fluent 2022 R1 was used for steady-state calculations, with a single-phase simulation system, providing assistance for optimizing the structure of the stirred reactor during epoxy resin adhesive mixing. The pressure-velocity coupled solution method, SIMPLE, was used, with the impeller speed set to 300 rpm and the stirring direction counterclockwise. The convergence residual was set to 10. -5 .

[0052] In the numerical simulation, the origin of the coordinate system was set at the top of the centerline of the stirring shaft, with upwards being positive. To ensure the accuracy of the simulation, the impeller and shaft regions underwent mesh refinement. Due to the presence of many sharp areas in the geometric model, an unstructured hybrid mesh type was used for mesh generation. Mesh independence verification showed that the number of meshes had a negligible impact on the velocity distribution in the simulation system. Therefore, to save computational resources, the mesh size was selected as follows: 906949 for the single-tooth shaft stirred tank, 908350 for the eccentric single-tooth shaft stirred tank, 1157507 for the uniaxial single-blade impeller-single-tooth dual-shaft stirred tank, and 1399496 for the biaxial single-blade impeller-single-tooth triaxial stirred tank.

[0053] Based on this, this embodiment utilizes CFD computational fluid dynamics to investigate the influence of different stirred reactors on the mixing performance of high-viscosity materials, as detailed below:

[0054] (1) Fluid trajectory:

[0055] At 300 r / min on the serrated disc shaft -1 Axial single impeller shaft 100 r·min -1 At different rotational speeds, the flow trajectories inside the four types of stirred reactors are as follows: Figure 3 As shown. Figure 3 Image (a) shows the overall fluid trajectory of the serrated disc agitator under high-viscosity material conditions. It can be observed that it mainly consists of regional stratification of the isolation zone and an ordered, symmetrical axial trajectory. The upper part of the trajectory is affected by the accumulation of high-viscosity material due to the climbing of the shaft and impeller rotation. After changing the impeller position (…), Figure 3 In (b), the symmetrical trajectory is deflected. Some materials are squeezed towards a certain area by the combined action of gravity and the rotational force of the agitator, resulting in a slight axial flow trajectory. However, this also exposes the problem of a large non-eccentric end isolation zone and insufficient flow. Figure 3 Figure (b) shows the three-dimensional fluid trajectory distribution after the introduction of the axial single-blade impeller. It can be observed that the introduction of the axial single-blade impeller significantly improves the anisotropic flow of the fluid within the stirred tank. Furthermore, the fluid is not only mixed axially by the collision between the serrated disc impeller and the tank wall, but also by the rotation of the axial single-blade impeller in the upper and lower regions, effectively reducing the problem of insufficient flow in the mixing isolation zone and at the non-eccentric ends. The internal three-dimensional fluid trajectory distribution of the dual single-blade axial flow-serrated disc triaxial mixing and stirring device is as follows: Figure 3 As shown in (d), it can be seen that compared to Figure 3 In the middle (c), the mixing flow in the upper and lower regions is more concentrated. The axial streamlines that should appear around the serrated disc impeller are also changed by the rotation of the two axial single blade shafts. The coverage of the fluid flow trajectory in the stirred tank is also higher, indicating that the mixing performance of this stirring device is better without considering power consumption.

[0056] (2) Velocity distribution:

[0057] At 300 r / min on the serrated disc shaft -1 Axial single impeller shaft 100 r·min -1 At different rotational speeds, the velocity distribution and internal flow trajectories of the four stirred reactors are as follows: Figure 4 As shown. Based on the distance from the serrated disc impeller, this embodiment divides the mixing vessel into two regions—the near-serrated impeller region (A) and the far-serrated impeller region (B). Figure 4 As shown in (a), the single-serrated disk turbine stirred tank generates a symmetrical stirring cycle for the high-viscosity fluid. Typical symmetrical saddle vortices, characteristic of high-viscosity laminar flow, appear in region B, indicating that this region is largely within the mixing isolation zone. Similarly, symmetrical annular vortices appear in region A, which would hinder overall mixing within the stirred tank. The YZ velocity distribution cross-section of the eccentric serrated disk turbine stirred tank is shown in Figure [Figure number missing]. Figure 4As shown in (b), changing the position of the stirring shaft and impeller from the center to the eccentric breaks its symmetrical flow field structure, almost eliminates the annular vortex in region A, and greatly compresses the isolation zone near the impeller end in region B. However, this also makes the isolation zone at the distal end larger and more difficult to mix.

[0058] To address this isolation zone issue, this embodiment introduces a low-speed axial single-propeller shaft at the distal end of the eccentric shaft, such as... Figure 4 As shown in (c), the flow field after adding the axial single propeller shaft exhibits a significant amount of disordered flow. This drastically reduces the isolation regions in A and B, breaking down the originally large isolation areas into smaller vortices and increasing the overall chaotic mixing in the flow field. However, after introducing two axial single propeller shafts, as shown in [the diagram]... Figure 4 As can be seen in (d), the degree of disorder in the flow field is higher and there are more small eddies. Therefore, it is preliminarily judged that the mixing effect of the material in the flow field is better.

[0059] The above results verify that introducing an axial single-blade impeller can effectively increase the axial flow of high-viscosity fluids, thereby effectively improving the mixing in the upper and lower regions and addressing the mixing isolation zone problem of the single-serrated disk impeller. Simultaneously, the coupling effect of the axial single-blade impeller and the serrated disk impeller increases the randomness of fluid flow, enhancing the disordered flow of high-viscosity fluids in the stirred tank and improving the mixing effect.

[0060] To further reveal the mechanism by which the spatial position and structure of different impellers regulate the flow field distribution and mixing degree within the stirred tank, this embodiment divides four different stirred tanks into two groups: the first group is a single-shaft group, including a single-sawtooth dispersion stirred tank (SSDM) and an eccentric sawtooth dispersion stirred tank (ESSDM), with the distance from the impeller in this group being [missing information]. , and The velocities in the three axial directions are analyzed. The first group represents the distance from the center of the stirring shaft to the location where the value is taken. The second group consists of multi-shaft vessels, including a uniaxial single-blade impeller-single-serrated biaxial stirred tank (ESDM-SAS) and a biaxial single-blade impeller-single-serrated triaxial stirred tank (ESDM-DSAS). The location of the stirred tank in this group is... , and The velocities in the three axial directions are analyzed. The distance from the center of the stirred tank to the location where the value is taken is, such as... Figure 5 As shown.

[0061] By analyzing the velocity distribution at different spatial locations, it was found that the flow field in the single-shaft stirred tank... and The axial, radial, and tangential velocity distributions at the location are relatively similar, while... The axial velocities at different locations vary significantly; the axial velocity distribution of the SSDM is close to zero, while the ESSDM exhibits fluctuations in its velocity distribution. This is due to... In SSDM, the impeller-generated ripples are located close to the vessel wall, and most of their kinetic energy is absorbed by the material and the vessel wall as they reach this location; whereas in ESSDM... The impeller is positioned at the center of the non-eccentric end. This further demonstrates that an eccentrically placed impeller has a better dispersion effect on high-viscosity flow fields than a centrally placed one. Furthermore, both the SSDM and ESSDM exhibit peak values ​​in both axial and tangential velocities, while the radial velocity changes relatively smoothly, indicating that the toothed dispersion disk has a better effect on both axial and tangential velocities in high-viscosity flow fields.

[0062] Compared to a single axis, the introduction of a differential axis has a greater impact on the velocity distribution at the upper end of the flow field, and multiple peaks exist in the velocity distribution at the same location, indicating that the introduction of the differential axial flow axis has a certain modulating effect on the overall velocity distribution of the flow field. However, the velocity distribution in all directions of the flow field in the non-eccentric end of the ESDM-DSAS is more gradual than that in the ESDM-DSAS asymmetric model. This is because the two differential axial flow axes in the ESDM-DSAS asymmetric model almost completely block the fluctuations of the high-speed toothed dispersion disk.

[0063] This embodiment further analyzes the mixing performance of different stirred tanks using isosurfaces and vorticity. This embodiment selects isosurfaces with velocities of 0.01 m / s, 0.05 m / s, 0.1 m / s, and 0.2 m / s to analyze the effects of different stirred reactors. It was found that when the velocity isosurface is equal to 0.01 m / s, there is still a large blank area at the upper part of the SSDM and ESSDM, indicating that regardless of whether it is placed eccentrically or centrally, a single serrated disc impeller cannot completely cover the mixing of the upper and lower halves; while the upper and lower halves of the ESDM-SAS and ESDM-DSAS stirred tanks are mostly within the isosurface.

[0064] At velocity isosurfaces of 0.1 m / s and 0.2 m / s, the velocity isosurface distribution of all agitators is mainly concentrated in the impeller / blade region. Furthermore, at higher velocity isosurfaces, the impellers of the multi-shaft system hardly influence each other. This phenomenon is due to the high viscosity of the material in the stirred tank, which severely hinders the transfer of kinetic energy from the impeller rotation. Therefore, to enhance the mixing of highly viscous materials in the agitator and transform regional mixing into global mixing, it is necessary to introduce a differential-speed axial single-blade.

[0065] Furthermore, by analyzing the isosurface distribution of different vorticities in different stirred reactors at the same stirring speed, it was found that under low vorticity conditions ( At first, the eccentric placement of the main impeller did indeed cause changes in the vortex structure, but the changes were minor. However, after introducing the differential axial single impeller shaft, the flow field inside the stirred tank changed significantly, and the vortex structure around the main impeller also underwent combined changes due to the influence of the differential shaft. But as the vortex value increased, the influence of the eccentric main shaft and the differential shaft on the vortex structure around the main shaft became smaller and smaller. At that time, the vorticity isosurface around the sawtooth disc impeller remained basically unchanged. This was due to the high viscosity of the material, which hindered the transfer of kinetic energy, and the large distance between the stirring shafts in the same device, which prevented them from forming a combined effect. This is consistent with the results of the velocity isosurface analysis mentioned above.

[0066] (3) Mixing time:

[0067] Figure 6 The study demonstrates the change in dimensionless concentration of liquid tracers over time in different stirred reactors with rotational speeds ranging from 300 r / min to 100 r / min. In each stirred reactor, the dimensionless concentration curve gradually converges to a stable value over time.

[0068] The mixing times for high-viscosity materials in different stirred reactors were 141.87 s, 135.32 s, 122.81 s, and 117.04 s, respectively. It can be observed that, under the same conditions, the placement of the eccentric impeller shortened the mixing time by 4.62%, and the introduction of differential axial single-paddle shafts (ESDM-SAS and ESDM-DSAS) shortened the mixing time by 13.43% and 17.5%, respectively. These results indicate that the eccentric placement of the impeller and the introduction of differential axial single-paddle shafts have a positive impact on the mixing of materials in the stirred reactor, with the latter showing a greater reduction in mixing time, demonstrating its stronger mixing ability for high-viscosity materials.

[0069] As shown in the figure, the mixing time in both the SSDM and ESSDM units decreases significantly with increasing rotational speed, while the mixing time in the ESDM-SAS and ESDM-DSAS units decreases at a slower rate. Overall, at the same sawtooth shaft rotational speed, the mixing time in the SSDM and ESSDM units is longer than that in the ESDM-SAS and ESDM-DSAS units. Meanwhile, the mixing times in the ESDM-SAS and ESDM-DSAS units are relatively close at the same rotational speed, indicating that under certain conditions, the introduction of a uniaxial single-paddle shaft has met the mixing requirements.

[0070] To further analyze and verify, this embodiment also compared the power per unit volume of different stirred reactors, such as... Figure 7 As shown. From Figure 7As can be seen in (a), the ESDM-SAS and ESDM-DSAS devices, due to the addition of a differential axial single-paddle shaft, have significantly higher energy consumption per unit volume than the SSDM and ESSDM at the same sawtooth shaft speed. In summary, the introduction of a differential axial single-paddle shaft effectively enhances the overall mixing effect of high-viscosity materials in the stirred reactor, but also significantly increases its energy consumption per unit volume.

[0071] Figure 7 Figure (b) shows a line graph of mixing time and power consumption per unit volume. A smaller Y-coordinate indicates a shorter mixing time, and a smaller X-coordinate indicates lower power consumption. Therefore, the closer the graph is to the origin (Lower power consumption), the shorter the mixing time and the better the mixing effect, achieved with lower power consumption. It can be seen that ESDM-SAS, compared to the other three mixing devices, achieves a shorter mixing time with lower power consumption per unit volume. This confirms that after introducing a differential axial single-paddle shaft, a single shaft is sufficient to enhance the mixing of high-viscosity fluids. The enhancement effect of a dual differential axial single-paddle shaft is not significant, and its power consumption is also higher, failing to meet the requirement of "reducing power consumption while ensuring a shorter mixing time." Therefore, when mixing high-viscosity materials, introducing a differential axial single-paddle shaft for enhanced mixing is a good choice, and the mixing efficiency and performance of a mixing device with one axial single-paddle shaft are greater than those with multiple axial single-paddle shafts.

[0072] Example 2

[0073] Since the addition of inorganic fillers can improve the mechanical properties, anti-aging properties, and corrosion resistance of adhesives, it is common to add different types and proportions of particulate fillers during the preparation of adhesives.

[0074] Based on this, the present invention designs different speed ratios between the main shaft (toothed dispersion shaft) and the auxiliary shaft (axial single impeller shaft), and then combines them with different fillers or different filler ratios to verify the dispersion effect of a multi-shaft differential stirring structure optimization method applied to adhesive production on different fillers.

[0075] When the speed ratio is 3:1 (main shaft: auxiliary shaft), the packing dispersion and mixing conditions at packing ratios of 10%, 20%, 30%, and 40% are as follows: Figure 8 As shown in the figure, it can be seen that the mixing time decreases with the increase of the filler ratio, but the mixing time becomes stable when the filler ratio reaches more than 30%.

[0076] When the speed ratio is 2:1 (main shaft: auxiliary shaft), the packing dispersion and mixing conditions at packing ratios of 10%, 20%, 30%, and 40% are as follows: Figure 9As shown in the figure, under this rotational speed ratio, as the proportion of packing increases, the mixing time decreases and the mixing effect improves.

[0077] When the speed ratio is 1:1 (main shaft: auxiliary shaft), the packing dispersion and mixing conditions at packing ratios of 10%, 20%, 30%, and 40% are as follows: Figure 10 As shown. Figure 10 As shown in (a), when the filler content is 10%, the dimensionless concentration does not reach the 95% principle at stable conditions. Therefore, it can be concluded that at this speed ratio, 10% filler is difficult to mix evenly. When the filler content is 20%, the mixing time is shorter, while at 30% and 40%, the mixing time is much longer than at speed ratios of 3:1 and 2:1. This means that under high filler content conditions, a stirring device with a high speed ratio difference can quickly mix the filler evenly in high-viscosity materials.

[0078] In this embodiment, mixing time is used to quantify the mixing effect and comprehensively evaluate the mixing effect of different packing ratios at different speed ratios, such as... Figure 11 As shown, it can be seen that the mixing of high filler ratio materials is more stable at high speed ratios. Therefore, for materials with high filler ratios, a speed ratio of 3:1 (main shaft: auxiliary shaft) is preferred.

[0079] Therefore, the present invention adopts the above-mentioned multi-axis differential speed stirring structure optimization method applied to adhesive production, and introduces an eccentric impeller and a differential axial single impeller shaft, which can significantly break the symmetrical flow field, reduce the chaotic isolation zone, enhance the axial flow of materials and overall chaotic mixing, thereby effectively shortening the mixing time.

[0080] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for optimizing a multi-shaft differential stirring structure used in adhesive production, characterized in that, It includes a multi-shaft differential speed stirring vessel, which consists of an eccentric toothed dispersion shaft and an axial single impeller shaft. The impellers of the eccentric toothed dispersion shaft and the axial single impeller shaft are respectively toothed disc impellers and axial flow single-blade impellers. The multi-shaft differential speed stirred tank is used for high-viscosity fluids with different packing ratios. An eccentric toothed dispersion shaft serves as the main shaft, and an axial single impeller shaft serves as the auxiliary shaft. The speed ratio between the main shaft and the auxiliary shaft is set between 1 and 3. In a 30% high-viscosity fluid, a high rotational speed ratio is selected for material mixing, with the ratio of main shaft to auxiliary shaft set to 3:

1.

2. The method for optimizing a multi-axis differential stirring structure applied to adhesive production according to claim 1, characterized in that, The positions of the eccentric toothed dispersion shaft and the axial single impeller shaft are determined comprehensively based on velocity distribution, flow trajectory, mixing time, and power consumption per unit volume in the multi-axis differential stirring vessel.

3. The method for optimizing a multi-axis differential stirring structure applied to adhesive production according to claim 2, characterized in that, The axial single propeller shaft is located at the distal end of the eccentric toothed dispersion shaft, and a single axial single propeller shaft is selected to enhance the mixing effect while maintaining low power consumption per unit volume.

4. The method for optimizing a multi-axis differential stirring structure applied to adhesive production according to claim 1, characterized in that, When multi-shaft differential speed stirred tanks are used for high-viscosity fluids, a strategy of using a high-speed eccentric toothed dispersion shaft and a low-speed axial single impeller shaft is adopted.

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