Flow field regulating device and regulating method for porous media

Abstract

The application provides a flow field adjusting device for a porous medium and a method for adjusting the flow field of the porous medium by using the device. The flow field adjusting device comprises a plurality of concentric ring components capable of rotating relative to each other, each of the concentric ring components comprising: a plurality of first structural units; and a plurality of second structural units arranged alternately with the plurality of first structural units in the circumferential direction, the first structural units and the second structural units having different anisotropic characteristics, wherein the radial thickness of the plurality of concentric ring components gradually increases from inside to outside.

Description

Technical Field

[0001] This application relates to the field of porous media regulation technology, specifically to a flow field regulation device for porous media and a method for regulating the flow field of porous media using the device. Background Technology

[0002] Porous media are shared spaces occupied by multiphase materials, and are also a combination of multiphase materials coexisting. They consist of a framework of solid materials and a large number of densely packed micropores separated by the framework. Fluids within porous media move by seepage. The main physical characteristics of porous media are small pore size and large specific surface area.

[0003] The internal environment of the human body, as well as media such as soil, are typical porous media flow field systems. Currently, the problem of how to regulate the flow field within porous media (e.g., adjusting flow direction and / or velocity) remains unsolved. This presents a potential need in fields such as microfluidics and biomedicine. Summary of the Invention

[0004] To address the aforementioned problems in the prior art, this application provides a flow field adjustment device for porous media and a method for adjusting the flow field of porous media using the device.

[0005] According to one aspect of this application, a flow field conditioning device for porous media is provided, comprising a plurality of concentric ring components rotatable relative to each other, each of the concentric ring components comprising:

[0006] Multiple first structural units; and

[0007] Multiple second structural units are alternately arranged with the multiple first structural units in the circumferential direction, and the first structural units and the second structural units have different anisotropic characteristics.

[0008] The radial thickness of the plurality of concentric ring components gradually increases from the inside to the outside.

[0009] According to one embodiment, the radial permeability of the first structural unit is greater than the tangential permeability, preferably greater than 5-20 times the tangential permeability, more preferably 10 times the tangential permeability, and the tangential permeability of the second structural unit is greater than the radial permeability, preferably greater than 5-20 times the radial permeability, more preferably 10 times the radial permeability.

[0010] According to one embodiment, each of the first structural units includes one or more pillars, preferably two pillars, evenly distributed circumferentially to divide the first structural unit into multiple radially permeable regions, wherein the size of the pillars in the first structural unit of the multiple concentric ring components gradually increases from the inside to the outside.

[0011] According to one embodiment, each of the second structural units includes a plurality of radial blocking blocks evenly distributed along the circumference, preferably three radial blocking blocks, with gaps between adjacent radial blocking blocks, and the number and position of the gaps in each of the second structural units correspond to the number and position of the columns in each of the first structural units.

[0012] According to one embodiment, the flow field adjustment device further includes:

[0013] A driver for driving the rotational movement of each of the concentric ring components; and / or

[0014] Multiple protrusions are respectively fixed to the top or bottom of the multiple concentric ring components in the axial direction, so as to drive the multiple concentric ring components to rotate.

[0015] According to one embodiment, the number of the plurality of concentric ring components is an odd number, preferably 7, 9 or 11.

[0016] According to one embodiment, in each of the concentric ring components, the plurality of first structural units and the plurality of second structural units are uniformly distributed circumferentially, and each has the same phase angle. The inner and outer diameters of each of the concentric ring components satisfy the following formula:

[0017]

[0018] Where r i r represents the inner diameter of the i-th concentric ring component from the inside out. i+1 This represents the outer diameter of the i-th concentric ring component from the inside out.

[0019] According to one embodiment, the ratio of the inner diameter of the innermost concentric ring component to the outermost concentric ring component is 1:1.8 to 2.4, preferably 30:63.4, and...

[0020] The ratio of the inner diameter of the innermost concentric ring component to the size of the solid phase in the porous medium is 10 to 20:1, preferably 15:1.

[0021] According to one embodiment, the ratio of the axial dimension of each of the plurality of concentric ring components to the inner diameter of the innermost concentric ring component is 1:30 to 150.

[0022] According to one embodiment, the plurality of concentric ring components contain an equal number of first structural units and an equal number of second structural units.

[0023] According to one embodiment, the diameter of the column in the first structural unit of the outermost concentric ring component of the plurality of concentric ring components corresponds to the size of the solid phase in the porous medium, and the ratio of the diameter of the column in the first structural unit of the outermost concentric ring component of the plurality of concentric ring components to the inner diameter of the innermost concentric ring component is 1:10 to 20, preferably 1:15.

[0024] According to one embodiment, the phase angle of each gap is 0.5 to 1.5°, preferably 1°.

[0025] According to another aspect of this application, a method for regulating the flow field of a porous medium using the flow field regulating device described above is provided, comprising:

[0026] The flow field conditioning device is placed inside the porous medium; and

[0027] The relative positions of the multiple concentric ring components in the circumferential direction are adjusted so that each pair of adjacent concentric ring components differs by a predetermined phase angle, thereby making the flow direction of the flow field inside the multiple concentric ring components different from the background flow field of the porous medium.

[0028] According to one implementation, the method further includes:

[0029] By continuously adjusting the phase angle difference between every two adjacent concentric ring components, the flow direction of the flow field inside the multiple concentric ring components changes continuously.

[0030] According to another aspect of this application, a method for regulating the flow field of a porous medium using the flow field regulating device described above is provided, comprising:

[0031] The flow field conditioning device is placed inside the porous medium; and

[0032] The relative positions of the even-numbered concentric ring components with respect to the odd-numbered concentric ring components in the circumferential direction are adjusted such that the even-numbered concentric ring components are aligned with each other, the odd-numbered concentric ring components are aligned with each other, and the even-numbered concentric ring components are out of phase with the odd-numbered concentric ring components by a predetermined phase angle, thereby making the flow velocity inside the multiple concentric ring components different from the background flow field of the porous medium.

[0033] According to one implementation, the method further includes:

[0034] By continuously adjusting the phase angle between the concentric ring components of even-numbered rings and those of odd-numbered rings, the flow velocity within the multiple concentric ring components can be continuously varied.

[0035] Therefore, with the above configuration, the flow field of porous media can be adjusted using a flow field adjustment device. Since the multiple concentric ring components of the device contain alternating structural units, and the two structural units have different anisotropic characteristics, the device can continuously adjust the flow velocity and / or flow direction of the flow field located inside the multiple concentric ring components without disturbing the external flow through simple rotation. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 A schematic cross-sectional view of a flow field conditioning device for porous media according to one embodiment of this application is shown.

[0038] Figure 2 A computer simulation schematic diagram of a flow field conditioning device located in a porous medium according to one embodiment of this application is shown.

[0039] Figure 3 It shows Figure 2 A partial enlarged view of the first and second structural units in the flow field adjustment device shown.

[0040] Figure 4 A schematic cross-sectional view of a flow field conditioning device for porous media according to another embodiment of this application is shown.

[0041] Figure 5 It shows Figure 4 A perspective view of the rear of the flow field regulating device shown.

[0042] Figure 6 The visualization shows the effect of different configurations of the flow field adjustment device according to this application placed in a porous media flow field, wherein, Figure 6 The ac section shows three typical configurations of the flow field regulating device according to this application, the df section shows the pressure field distribution corresponding to the ac configuration, and the gi section shows the streamline distribution corresponding to the ac configuration.

[0043] Figure 7The curve showing the relationship between the adjustment angle and the deviation angle of the flow field direction in the rotation mode of the flow field adjustment device according to this application is illustrated.

[0044] Figure 8 The curve showing the relationship between the adjustment angle and the flow velocity of the flow field in the rotation mode of the flow field adjustment device according to this application is illustrated.

[0045] Figure 9 A flowchart is shown of a method for adjusting the flow field of a porous medium using a flow field adjustment device according to one embodiment of this application.

[0046] Figure 10 A flowchart is shown of a method for adjusting the flow field of a porous medium using a flow field adjustment device according to another embodiment of this application.

[0047] Figure 11 A flowchart is shown of a method for adjusting the flow field of a porous medium using a flow field adjustment device according to one embodiment of this application.

[0048] Figure 12 A flowchart is shown of a method for adjusting the flow field of a porous medium using a flow field adjustment device according to another embodiment of this application.

[0049] Figure 13 A schematic diagram illustrating the actual performance of a flow field conditioning device as a microfluidic device according to one embodiment of this application in a porous media flow field is shown. Figure 13 Part a shows the fluorescence microscope equipment used to observe the flow field; part b shows the PDMS lithography system and microfluidic structure design; part ce (which can be referred to as the "cloak," "concentrator," and "rotator") corresponds to... Figure 6 The ac section shows the streamline diagrams of the flow field of the device in different rotation modes; the fh section shows the flow field in the central region marked by the yellow square in the ce section.

[0050] Figure 14 A schematic diagram illustrating the actual performance of a flow field regulating device as a macroscopic device according to one embodiment of this application in a porous media flow field is shown. Figure 14In the diagram, section ac shows photographs of flow field modulation devices fabricated by 3D printing as macroscopic devices in configurations of "cloak," "concentrator," and "rotator," achieved by continuously rotating concentric ring components of corresponding layers within the device; section df shows the flow fields corresponding to different structures obtained by tracking tracer particles (polystyrene particles with a radius of 10 μm), with velocity magnitudes represented by different colors; section gh schematically shows the front and back views of the actual device; section ij shows the 3D design drawings corresponding to section gh; section k shows a comparison of the rotational flow field angles between experiments and simulations, where blue symbols are from theoretical simulations, orange symbols are from microfluidic devices, and red symbols are from macroscopic devices; section l shows a comparison of velocity magnitudes between two experimental samples and simulations. Detailed Implementation

[0051] To better understand the technical solutions and advantages of this application, the content of this application will be further described in detail below with reference to the accompanying drawings and specific embodiments. However, the specific embodiments described herein are only used to explain this application and are not intended to limit this application. In addition, the technical features involved in the various embodiments of this application described below can be combined and used, except where they conflict with each other, to constitute other embodiments within the scope of this application.

[0052] The following description provides many different implementations or examples for carrying out different structures of this application. To simplify the disclosure of this application, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or reference letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various implementations and / or arrangements discussed.

[0053] Figure 1 A schematic cross-sectional view of a flow field regulating device for porous media according to one embodiment of this application is shown. This flow field regulating device 100 can be applied to porous media to regulate the flow field within the porous media, for example, regulating the flow direction and velocity. Figure 1As shown, the flow field adjustment device 100 may include a plurality of concentric ring components 110, each concentric ring component 110 having a radial thickness that gradually increases from the inside to the outside. Each concentric ring component 110 can rotate circumferentially relative to each other under the control of a driver (not shown) or by manual adjustment, and each concentric ring component 110 includes a plurality of first structural units 111 and a plurality of second structural units 112. In each concentric ring component 110, the first structural units 111 and the second structural units 112 are alternately arranged in the circumferential direction, and they have different anisotropic characteristics. For example, the radial permeability of the first structural unit 111 may be greater than its tangential permeability, and the tangential permeability of the second structural unit 112 may be greater than its radial permeability, thereby allowing the first structural units 111 and the second structural units 112 to have different anisotropic characteristics in the porous medium flow field.

[0054] Thus, with the above configuration, the flow field of the porous medium can be adjusted using the device 100. Since the multiple concentric ring components of the device contain alternating structural units, and the two structural units have different anisotropic characteristics, the device can continuously adjust the flow velocity and / or flow direction of the flow field located inside the multiple concentric ring components without disturbing the external flow (which will be described in detail below) by simply rotating the device.

[0055] In porous media flow fields, according to simplified fluid equations, transport properties depend only on the permeability of the medium. The process control device of this application can operate without affecting the external field because its structure's equivalent permeability is consistent with the equivalent permeability of the external background. Equivalent permeability is an approximation of the actual effect of a device with anisotropic permeability in a flow field. That is, an anisotropic device is equated to an isotropic and homogeneous material with a constant permeability. Through calculation and simulation, the influence of homogeneous and anisotropic materials on the surrounding flow field is made consistent, and the permeability of the homogeneous material is taken as the equivalent permeability of the anisotropic device. This equivalence concept is summarized as the effective medium approximation theory. Therefore, by placing the process control device of this application in a porous media flow field, the internal flow field can be adjusted by regulating the relative displacement between the concentric ring components without affecting the external environment.

[0056] According to one embodiment of this application, in order to obtain a better flow field regulation effect in a porous medium, the radial permeability of the first structural unit 111 needs to be much greater than its tangential permeability, for example, greater than 5-20 times, preferably 10 times. On the other hand, the tangential permeability of the second structural unit 112 needs to be much greater than its radial permeability, for example, greater than 5-20 times, preferably 10 times.

[0057] According to another embodiment of this application, the number of first structural units 111 included in each of the plurality of concentric ring components 110 is equal, and the number of second structural units 112 included in each of them is also equal, such as... Figure 1 As shown.

[0058] Figure 2 A computer simulation schematic diagram of a flow field conditioning device located in a porous medium according to one embodiment of this application is shown. Figure 3 It shows Figure 2 A partial enlarged view of the first and second structural units in the flow field adjustment device shown.

[0059] like Figure 2 and Figure 3 As shown, each first structural unit 111 may include one or more pillars 111A (e.g., two pillars shown in the figure) evenly distributed circumferentially to divide the first structural unit 111 into multiple radial permeation regions. This arrangement allows the radial permeability of the first structural unit 111 to be much greater than its tangential permeability, achieving a better flow field regulation effect. Furthermore, to obtain a better flow field regulation effect in porous media, in each concentric ring component 110, the size of the pillars 111A in the first structural unit 111 gradually increases from the inside to the outside.

[0060] Furthermore, each second structural unit 112 may include a plurality of radially blocking blocks 112A (e.g., three radially blocking blocks shown in the figure) evenly distributed along the circumference, with gaps 112B between adjacent radially blocking blocks 112A. This arrangement allows the tangential permeability of the second structural unit 112 to be much greater than its radial permeability, thereby achieving a better flow field regulation effect. Figure 2 and Figure 3 As shown, the number and position of the gaps 112B in each second structural unit 112 correspond to the number and position of the columns 111A in each first structural unit 111.

[0061] According to one embodiment of this application, in a plurality of concentric ring components 110, the ratio of the inner diameter of the innermost concentric ring component to the outer diameter of the outermost concentric ring component is 1:1.8 to 2.4, and the ratio of the inner diameter of the innermost concentric ring component to the size of the solid phase in the porous medium is 10 to 20:1. When the dimensions of the concentric ring components 110 satisfy this proportional relationship, the flow field adjustment device can achieve a better flow regulation effect on the porous medium (described in detail below with reference to test results). For example, referring again... Figure 2 The dimensions shown are dimensionless because all structural dimensions in this application can be scaled proportionally. For example... Figure 2As shown, the ratio of the inner diameter *a* of the innermost concentric ring component to the outer diameter *b* of the outermost concentric ring component is *a:b* = 30:63.4, and the ratio of the inner diameter *a* of the innermost concentric ring component to the size *d* of the solid phase in the porous medium is *a:d* = 30:2 (i.e., 15:1). Furthermore, the spacing of the solid phase in the porous medium can be, for example, *s* = 3, but this application is not limited to this.

[0062] Those skilled in the art will understand that the structural dimensions in this application can be scaled proportionally according to the application scenario, and this scaling is applicable from the microfluidic scale (1nm-1mm scale) to the macroscopic scale. The impact of different scales on the effect lies in the observation range within which the flow field adjustment device can maintain its stealth effect (without affecting its external flow field). In other words, as long as the observer's observation range is greater than the size of the smallest structural unit, the flow field adjustment device can be considered to remain stealthy within the flow field (the existence of the structure has no effect on the external field).

[0063] According to another embodiment of this application, in a plurality of concentric ring components 110, the ratio of the axial dimension (i.e., its thickness) of each concentric ring component 110 to the inner diameter of the innermost concentric ring component is 1:30 to 150.

[0064] According to one embodiment of this application, in a plurality of concentric ring components 110, the diameter of the column in the first structural unit 111 of the outermost concentric ring component corresponds to (e.g., equal to or approximately equal to) the size of the solid phase in the porous medium, and in a plurality of concentric ring components 110, the ratio of the diameter of the column in the first structural unit 111 of the outermost concentric ring component to the inner diameter of the innermost concentric ring component is 1:10 to 20, for example 1:15.

[0065] According to one embodiment of this application, the flow field adjustment device may further include a driver (not shown) for driving the rotational movement of each concentric ring component 110. Those skilled in the art will understand that the driver can control the rotational movement of each concentric ring component 110 in any known manner, for example, through the cooperation of a motor and gears to achieve remote control and more precise rotational control. For the sake of brevity, further details are omitted here.

[0066] Figure 4 A schematic cross-sectional view of a flow field conditioning device for porous media according to another embodiment of this application is shown. Figure 5 It shows Figure 4 A perspective view of the rear of the flow field conditioning device shown. Figure 4 and Figure 5As shown, the flow field adjustment device 100 may also include a plurality of protrusions 120, each of which may be fixed to the axial top or bottom of a plurality of concentric ring components 110, for driving the plurality of concentric ring components 110 to rotate (for example, the protrusions may be manually adjusted).

[0067] The two embodiments described above schematically illustrate different driving methods for the concentric ring components of the flow field adjustment device. However, this application is not limited thereto, and any driving method that can be conceived by those skilled in the art is within the scope of this application.

[0068] According to one embodiment of this application, the flow field adjustment device 100 includes an odd number of concentric ring components 110, so that in certain adjustment modes (detailed below), the rotation angles of the innermost and outermost concentric ring components correspond. According to one embodiment, the number of concentric ring components 110 can be 7, 9, or 11. In this application, an odd number of concentric ring components is required because it is necessary to ensure that... Figure 1 In the configuration shown, the relative positions of the basic structural units in the outermost ring must be consistent with those in the innermost ring. Otherwise, the internal flow velocity of the flow field regulating device 100 in this configuration cannot reach the design minimum value.

[0069] Refer to Figure 1 and Figure 2 As shown, in each concentric ring component 110, the first structural unit 111 and the second structural unit 112 are evenly distributed circumferentially, and each structural unit occupies the same phase angle. For example, such as Figures 1 to 3 As shown, each concentric ring component 110 includes 10 alternating first structural units 111 and 10 second structural units 112. The phase angle occupied by each structural unit is... The angle is 18°. If each first structural unit 111 includes two pillars 111A evenly distributed circumferentially, then each first structural unit 111 is divided into phase angles by the two pillars 111A within it. Three regions of 6° (e.g.) Figure 3 (As shown).

[0070] On the other hand, in the second structural unit 112, the phase angle occupied by each gap 112B between each radial blocking block 112A is... It can be 0.5 to 1.5°, for example, 1°.

[0071] Furthermore, the inner and outer diameters of each concentric ring component 110 satisfy the following formula:

[0072]

[0073] Where r i r represents the inner diameter of the i-th concentric ring component from the inside out. i+1 This represents the outer diameter of the i-th concentric ring component from the inside out. The geometric relationship in formula (1) determines whether the flow field regulating device 100 will affect the external field. If this geometric relationship is not satisfied, the equivalent permeability of the flow field regulating device 100 cannot match the external field, and will thus affect the external field. This formula is derived from making the equivalent permeability of the device equal to the geometric mean of the equivalent permeability of the two basic structural units.

[0074] According to formula (1) above, the more concentric rings the flow field regulating device 100 contains, the thicker the entire device will be in the radial direction (due to the ln relationship, the thickness will increase exponentially with each additional ring), and the more material will be required. If the number of rings is too small, the adjustment range of the flow velocity inside the device will be smaller. The ratio of the internal flow velocity to the background flow velocity is (a / b). h-1 Where h is the square root of the ratio of the radial to the tangential permeability of the device, a value determined by the basic structural unit. Therefore, once the basic structural unit is determined, the ratio of the internal and external flow velocities is determined by the device thickness, i.e., by the number of rings. Thus, the selection of the number of rings requires a certain balance between functionality and power consumption.

[0075] Refer again Figure 2 In this embodiment, the innermost concentric ring component of the flow field adjustment device 100 has an inner diameter a = 30 (dimensionless), and the outermost concentric ring component has an outer diameter b = 63.4 (dimensionless). The entire device comprises nine concentric ring components 110. Since the dimensions and thicknesses of the nine rings must satisfy the above formula (1), the cross-sectional radius of the column 111A in the first structural unit 111 of each ring component gradually decreases from the inside to the outside, and its dimensionless dimensions can be 2, 1.84, 1.70, 1.57, 1.44, 1.33, 1.23, 1.13, and 1.04, respectively. It is precisely because it is necessary to ensure that the ratio of tangential to radial permeability of each structural unit is consistent, and considering the relationship between the dimensions of the rings according to formula (1), that the thickness of the rings gradually decreases from the outside to the inside. Therefore, for each first structural unit 111, the column also gradually decreases from the outside to the inside.

[0076] Figure 6 The visualization shows the effect of different configurations of the flow field adjustment device according to this application placed in a porous media flow field, wherein, Figure 6 The ac section shows three typical configurations of the flow field regulating device according to this application, the df section shows the pressure field distribution corresponding to the ac configuration, and the gi section shows the streamline distribution corresponding to the ac configuration. Figure 7The curve showing the relationship between the adjustment angle and the deviation angle of the flow field direction in the rotation mode of the flow field adjustment device according to this application is illustrated. Figure 8 The curve showing the relationship between the adjustment angle and the flow velocity of the flow field in the rotation mode of the flow field adjustment device according to this application is illustrated.

[0077] As described above, the flow field adjustment device according to this application adjusts the flow field by rotating each of its concentric ring components. When the concentric ring components rotate in a specific pattern, the flow velocity and flow direction can be adjusted separately. Figure 6 In the example shown, the structure shown in part b is selected as the basic configuration. The detailed description below uses this basic configuration as the initial default structure of the flow field adjustment device.

[0078] I. Flow direction regulation:

[0079] like Figure 6 part c in Figure 7 As shown, in the flow direction adjustment mode within the device's internal region, the outermost concentric ring component can be kept stationary, while the other concentric ring components in the flow field adjustment device are rotated clockwise layer by layer, so that the phase difference angle between any two adjacent concentric ring components is α. For example... Figure 7 As shown, as α increases, it can be observed that the angle between the flow direction inside the device and the initial direction will change in a curve similar to a sine wave, with the theoretical adjustment angle ranging from -60° to +60° (the deviation angle is 0° in the initial state). Figure 6 Part c in the diagram shows the state where the flow direction inside the device deviates from the horizontal at its maximum, with a deviation angle of 60°.

[0080] Those skilled in the art will understand that the innermost or any intermediate concentric ring component can be kept stationary while the other concentric ring components rotate clockwise or counterclockwise to achieve the desired rotation angle and flow field deviation angle.

[0081] II. Flow rate regulation:

[0082] like Figure 6 part a in Figure 8 As shown, in the flow rate regulation mode within the device's internal region, the concentric ring components of odd-numbered layers (layers 1, 3, 5, 7, and 9) can remain stationary, while even-numbered layers (layers 2, 4, 6, and 8) can be rotated clockwise or counterclockwise by an angle β. For example... Figure 8As shown, regardless of how β changes, the background flow velocity (i.e., the flow velocity in the external region of the device) remains essentially constant at around 0.6 mm / s. This indicates that the flow field adjustment device according to this application does not affect the background flow velocity of the external flow field during the adjustment of the porous medium flow field, and the external flow field does not become distorted due to the presence of the flow field adjustment device. In the initial state (i.e., Figure 6 (As shown in section b), the flow velocity inside the device is at its maximum, approximately 1.0 mm / s, about 1.6 times the background flow velocity. As β increases, the flow velocity inside the device gradually decreases until it reaches... Figure 6 In the state shown in section a, the flow velocity inside the device is almost zero, and β = 18°. As β continues to increase, the flow velocity inside the device will gradually increase until it returns to its previous state. Figure 6 In the state shown in section b, the flow velocity inside the device increases again to its maximum value of approximately 1.0 mm / s. Theoretically, the flow velocity inside the device can be adjusted between approximately 0 and approximately 1.6 times the external flow velocity.

[0083] Those skilled in the art will understand that the concentric ring components of even-numbered layers can be kept stationary while the concentric ring components of odd-numbered layers can be rotated clockwise or counterclockwise to achieve the desired rotation angle and flow field velocity.

[0084] Figure 9 A flowchart illustrating a method for regulating the flow field of a porous medium using a flow field regulating device according to one embodiment of this application is shown. Figure 9 As shown, the method 200 may include steps S210 and S220.

[0085] In step S210, the flow field adjustment device is placed inside a porous medium. A background flow field already exists within this porous medium. As described above, based on the characteristics of the flow field adjustment device of this application, it does not affect the background flow field outside the device, but only adjusts its internal flow field.

[0086] In step S220, the relative positions of the multiple concentric ring components in the circumferential direction are adjusted so that each pair of adjacent concentric ring components differs by a predetermined phase angle, thereby making the flow direction of the flow field inside the multiple concentric ring components different from the background flow field of the porous medium. If a specific flow direction needs to be obtained within the flow field adjustment device, it can be determined according to... Figure 7 The relationship between the flow direction and phase angle α shown in the diagram allows us to determine the required rotation angle for each concentric ring component. This is done by moving each concentric ring component from... Figure 6 After the mode shown in section b is adjusted to the mode shown in section c (or a similar mode), the flow direction of the internal flow field of the device will be different from the background flow field of the porous medium, that is, the following will occur: Figure 7 The changes shown.

[0087] Therefore, by adjusting the two adjacent concentric ring components in the flow field adjustment device to differ by the same predetermined phase angle, the flow direction of the internal flow field of the device can be adjusted to the desired angle without affecting the background flow field outside the device.

[0088] Figure 10 A flowchart illustrating a method for regulating the flow field of a porous medium using a flow field regulating device according to another embodiment of this application is shown. Figure 10 As shown, in addition to steps S210 and S220, the above method 200 may also include step S230.

[0089] In step S230, the phase angle between each pair of adjacent concentric ring components is continuously adjusted, thereby causing the flow direction of the flow field inside the multiple concentric ring components to change continuously.

[0090] As described above, in the process of transferring multiple concentric ring components of the flow field adjustment device from... Figure 6 The pattern shown in part b is rotated to Figure 6 During the process shown in part c, the flow direction of the internal flow field of the device can change as follows: Figure 7 The continuous changes shown.

[0091] Figure 11 A flowchart illustrating a method for regulating the flow field of a porous medium using a flow field regulating device according to one embodiment of this application is shown. Figure 11 As shown, the method 300 may include steps S310 and S320.

[0092] In step S310, the flow field adjustment device is placed inside a porous medium. A background flow field already exists within this porous medium. As described above, based on the characteristics of the flow field adjustment device of this application, it does not affect the background flow field outside the device, but only adjusts its internal flow field.

[0093] In step S320, the relative positions of the even-numbered concentric ring components with respect to the odd-numbered concentric ring components in the circumferential direction are adjusted so that the even-numbered concentric ring components are aligned with each other, the odd-numbered concentric ring components are aligned with each other, and the even-numbered concentric ring components are separated from the odd-numbered concentric ring components by a predetermined phase angle, thereby making the flow velocity of the flow field inside the multiple concentric ring components different from the background flow field of the porous medium.

[0094] If a specific flow velocity needs to be obtained inside the flow field regulating device, it can be determined according to... Figure 8 The relationship between the flow velocity and the phase angle β shown in the diagram allows us to determine the required rotation angle for each concentric ring component. This is done by moving each concentric ring component from... Figure 6After the mode shown in part b is adjusted to the mode shown in part a (or a similar mode), the flow velocity inside the device will be different from the background flow field of the porous medium, that is, the following will occur: Figure 8 The changes shown.

[0095] Therefore, by adjusting the predetermined phase angle between the odd-numbered and even-numbered concentric ring components in the flow field adjustment device, the flow velocity inside the device can be adjusted to the desired value without affecting the background flow field outside the device.

[0096] Figure 12 A flowchart illustrating a method for regulating the flow field of a porous medium using a flow field regulating device according to another embodiment of this application is shown. Figure 12 As shown, in addition to steps S310 and S320, the above method 300 may also include step S330.

[0097] In step S330, the phase angle difference between the concentric ring components of the even-numbered rings and the concentric ring components of the odd-numbered rings is continuously adjusted, thereby causing the flow velocity of the flow field inside the multiple concentric ring components to change continuously.

[0098] As described above, in the process of transferring multiple concentric ring components of the flow field adjustment device from... Figure 6 The pattern shown in part b is rotated to Figure 6 During the process shown in part a, the flow velocity in the internal flow field of the device can change as follows: Figure 8 The continuous changes shown.

[0099] The flow field regulating device 100 according to this application can be fabricated using various processing techniques. For example, when the flow field regulating device 100 is small in size and serves as a microfluidic device, its scale is typical of microfluidics, and it can be fabricated using photolithography (e.g., PDMS photolithography). As another example, when the flow field regulating device 100 is of macroscopic device size, it can be fabricated using 3D printing technology.

[0100] Figure 13 A schematic diagram illustrating the actual performance of a flow field conditioning device as a microfluidic device according to one embodiment of this application in a porous media flow field is shown. Figure 13 Part a shows the fluorescence microscope equipment used to observe the flow field; part b shows the PDMS lithography system and microfluidic structure design; part ce (which can be referred to as the "cloak," "concentrator," and "rotator") corresponds to... Figure 6 The ac section shows streamline diagrams of the flow field in different rotation modes of the device; the fh section shows the flow field in the central region corresponding to the yellow square in the ce section. Figure 13In the diagram, the speed is represented by different colors, which is obtained through a large amount of statistical data from particle tracking, with "Cloak" having 820 particles, "Concentrator" having 1700 particles, and "Spinner" having 550 particles.

[0101] like Figure 13 The diagram shows a flow field modulation device fabricated using a PDMS lithography system as a microfluidic instrument, and its actual performance when placed in a porous media flow field. Flow field observation is achieved by scattering fluorescent tracer particles in the fluid. Flow velocity information can be measured based on the location of the marked particles and identified with different colors. Figure 13 It can be seen that this flow field adjustment device, as a microfluidic device, has a good modulation effect on the internal flow velocity and flow field, and has almost no effect on the external flow field, with the streamlines of the external flow field always remaining straight.

[0102] Figure 14 A schematic diagram illustrating the actual performance of a flow field regulating device as a macroscopic device according to one embodiment of this application in a porous media flow field is shown. Figure 14 In the diagram, section ac shows photographs of flow field modulation devices fabricated by 3D printing as macroscopic devices in configurations of "cloak," "concentrator," and "rotator," achieved by continuously rotating concentric ring components of corresponding layers within the device; section df shows the flow fields corresponding to different structures obtained by tracking tracer particles (polystyrene particles with a radius of 10 μm), with velocity magnitudes represented by different colors; section gh schematically shows the front and back views of the actual device; section ij shows the 3D design drawings corresponding to section gh; section k shows a comparison of the rotational flow field angles between experiments and simulations, where blue symbols are from theoretical simulations, orange symbols are from microfluidic devices, and red symbols are from macroscopic devices; section l shows a comparison of velocity magnitudes between two experimental samples and simulations.

[0103] like Figure 14 The image shows a macroscopic device with a continuously adjustable flow field, fabricated using 3D printing, and its actual performance when placed in a porous media flow field. The flow field is observed by scattering fluorescent tracer particles in the fluid. Flow velocity information can be measured based on the location of the marked particles and identified with different colors. Figure 14 It can be seen that the flow field adjustment device can continuously adjust the flow direction and velocity of its internal flow field, and has almost no effect on the external flow field.

[0104] Since the internal environment of the human body, as well as many fluid environments such as soil, are porous media flow field systems, the flow field regulation device according to this application has wide applicability. Due to its multifunctional switching capability and extremely minimal interference with the external environment, this application can be applied not only to fluid mechanics, including microfluidic control, but also to biomedical devices inside the human body, to fabricate non-invasive flow field regulation devices. This device can remain invisible in the flow field (i.e., its presence does not interfere with the external flow field, thus remaining invisible to external observers) and can continuously regulate the internal flow velocity and direction.

[0105] In the above embodiments, the descriptions of each embodiment have their own emphasis. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments. The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification.

[0106] The embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this application. Furthermore, any changes or modifications made by those skilled in the art based on the ideas of this application, and on the specific implementation methods and application scope of this application, are all within the scope of protection of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A flow field conditioning device for porous media, comprising a plurality of concentric ring components rotatable relative to each other, each of the concentric ring components comprising: Multiple first structural units; as well as Multiple second structural units are alternately arranged with the multiple first structural units in the circumferential direction. The radial permeability of the first structural units is greater than the tangential permeability, and the tangential permeability of the second structural units is greater than the radial permeability, so that the first structural units and the second structural units have different anisotropic characteristics in the porous media flow field. The radial thickness of the plurality of concentric ring components gradually increases from the inside to the outside.

2. The flow field regulating device as described in claim 1, wherein the radial permeability of the first structural unit is 5-20 times greater than the tangential permeability, and the tangential permeability of the second structural unit is 5-20 times greater than the radial permeability.

3. The flow field adjustment device as described in claim 2, wherein the radial permeability of the first structural unit is greater than 10 times the tangential permeability, and the tangential permeability of the second structural unit is greater than 10 times the radial permeability.

4. The flow field adjustment device as claimed in claim 1, wherein each of the first structural units includes one or more columns evenly distributed circumferentially to divide the first structural unit into multiple radially permeable regions, and the size of the columns in the first structural unit of the multiple concentric ring components gradually increases from the inside to the outside.

5. The flow field adjustment device as claimed in claim 4, wherein each of the first structural units comprises two columns evenly distributed circumferentially.

6. The flow field adjustment device as claimed in claim 4, wherein each of the second structural units includes a plurality of radially blocking blocks evenly distributed along the circumference, and there are gaps between adjacent radially blocking blocks, wherein the number and position of the gaps in each of the second structural units correspond to the number and position of the columns in each of the first structural units.

7. The flow field adjustment device as claimed in claim 6, wherein each of the second structural units includes three radially blocking blocks evenly distributed circumferentially.

8. The flow field adjustment device as described in claim 1, further comprising: A driver for driving the rotational movement of each of the concentric ring components; and / or Multiple protrusions are respectively fixed to the top or bottom of the multiple concentric ring components in the axial direction, so as to drive the multiple concentric ring components to rotate.

9. The flow field adjustment device as claimed in claim 1, wherein the number of the plurality of concentric ring components is an odd number.

10. The flow field adjustment device as claimed in claim 9, wherein the number of the plurality of concentric ring components is 7, 9 or 11.

11. The flow field adjustment device as claimed in claim 1, wherein in each of the concentric ring components, the plurality of first structural units and the plurality of second structural units are uniformly distributed circumferentially, and each has the same phase angle Δφ, and the inner and outer diameters of each of the concentric ring components satisfy the following formula: Where r i r represents the inner diameter of the i-th concentric ring component from the inside out. i+1 This represents the outer diameter of the i-th concentric ring component from the inside out.

12. The flow field adjustment device as claimed in claim 1, wherein the ratio of the inner diameter of the innermost concentric ring component to the outermost concentric ring component of the plurality of concentric ring components is 1:1.8~2.4, and The ratio of the inner diameter of the innermost concentric ring component to the size of the solid phase in the porous medium is 10 to 20:

1.

13. The flow field adjustment device as claimed in claim 12, wherein the ratio of the inner diameter of the innermost concentric ring component to the outermost concentric ring component of the plurality of concentric ring components is 30:63.4; The ratio of the inner diameter of the innermost concentric ring component to the size of the solid phase in the porous medium is 15:

1.

14. The flow field adjustment device as claimed in claim 1, wherein the ratio of the axial dimension of each of the plurality of concentric ring components to the inner diameter of the innermost concentric ring component is 1:30 to 150.

15. The flow field adjustment device as claimed in claim 1, wherein the plurality of concentric ring components contain an equal number of first structural units and an equal number of second structural units.

16. The flow field regulating device as claimed in claim 4, wherein the diameter of the column in the first structural unit of the outermost concentric ring component of the plurality of concentric ring components corresponds to the size of the solid phase in the porous medium, and the ratio of the diameter of the column in the first structural unit of the outermost concentric ring component of the plurality of concentric ring components to the inner diameter of the innermost concentric ring component is 1:10~20.

17. The flow field adjustment device as claimed in claim 16, wherein the ratio of the diameter of the column in the first structural unit of the outermost concentric ring component of the plurality of concentric ring components to the inner diameter of the innermost concentric ring component is 1:

15.

18. The flow field adjustment device as claimed in claim 6, wherein the phase angle of each of the gaps is 0.5 to 1.5°.

19. The flow field adjustment device of claim 18, wherein the phase angle of each of the gaps is 1°.

20. A method for regulating the flow field of a porous medium using the flow field regulating device according to any one of claims 1-18, comprising: The flow field adjustment device is placed inside the porous medium; as well as The relative positions of the multiple concentric ring components in the circumferential direction are adjusted so that each pair of adjacent concentric ring components differs by a predetermined phase angle, thereby making the flow direction of the flow field inside the multiple concentric ring components different from the background flow field of the porous medium.

21. The method of claim 20, further comprising: By continuously adjusting the phase angle difference between every two adjacent concentric ring components, the flow direction of the flow field inside the plurality of concentric ring components is continuously changed.

22. A method for adjusting the flow field of a porous medium using the flow field adjustment device according to any one of claims 1-18, comprising: The flow field adjustment device is placed inside the porous medium; as well as The relative positions of the even-numbered concentric ring components with respect to the odd-numbered concentric ring components in the circumferential direction are adjusted such that the even-numbered concentric ring components are aligned with each other, the odd-numbered concentric ring components are aligned with each other, and the even-numbered concentric ring components are out of phase with the odd-numbered concentric ring components by a predetermined phase angle, thereby making the flow velocity inside the multiple concentric ring components different from the background flow field of the porous medium.

23. The method of claim 22, further comprising: By continuously adjusting the phase angle between the concentric ring components of even-numbered rings and those of odd-numbered rings, the flow velocity within the multiple concentric ring components can be continuously varied.

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