Enhanced micro-mixing unit, micro-fluidic mixer and application

Abstract

The invention discloses an enhanced micro-mixing unit, a microfluidic mixer and application, and belongs to the technical field of microfluidics. The microfluidic mixer comprises an inlet flow channel, at least one contraction-expansion mixing flow channel and an outlet flow channel which are arranged in series, the inlet flow channel comprises a collecting flow channel; the contraction-expansion mixing flow channel comprises one enhanced micro-mixing unit or at least two enhanced micro-mixing units which are arranged in series; the mixing chamber is defined by an upper wall, a lower wall and symmetrically arranged side walls and used for mixing circulating feed liquid, the mixing chamber comprises a turbulent flow structure, and the turbulent flow structure comprises a fan-shaped retaining wall in a fan shape in the direction perpendicular to the feed liquid circulating direction and at least one pair of L-shaped protrusions in an L shape; by introducing the L-shaped bulge structures, the number of the serial micro-mixing units is reduced, the length of the whole flow channel is shortened, and efficient mixing of micro-fluids is completed under the condition of smaller volume dosage, so that the consumption of reagents is effectively reduced.

Description

Technical Field

[0001] The present application relates to an enhanced micro-mixing unit and a microfluidic mixer and applications, belonging to the field of microfluidic technology. Background Art

[0002] A microfluidic mixer is a mixing device implemented on a microfluidic technology platform that can quickly and evenly mix two or more different fluids under microscale conditions. The channel size of a microfluidic mixer is usually in the range of micrometers to millimeters, and the internal fluid flow is usually in a laminar state rather than traditional turbulence. Therefore, a specific flow channel design is required to promote mixing between different fluids. Existing studies have shown that TY-type micromixers, obstacle-type micromixers, and Tesla valve-type micromixers have shown good functions in promoting fluid mixing. However, these traditional micromixers have simple structures and uniform inner and outer diameters. These characteristics result in low mixing efficiency, and it is usually necessary to extend the channel length or connect multiple micromixing units of the same type in series to improve the mixing efficiency.

[0003] The patent with publication number CN117732385A is a typical technology for connecting multiple micro-mixing units of the same type in series to extend the channel length. Its technical solution shows that connecting multiple micro-mixing units containing obstacles or baffles in series can improve the mixing efficiency. However, due to the limitations of the series structure, it has problems such as large fluid injection volume and high reagent consumption. In addition, as the volume of the microfluidic mixer increases, the manufacturing process cost increases further. Summary of the invention

[0004] In order to solve the problem in the prior art that "the long microchannel structure in the series structure leads to a large amount of fluid to be mixed, which is difficult to meet the microfluidic production of expensive samples", the present application provides a design scheme for an enhanced micro-mixing unit and a microfluidic mixer. By introducing an L-shaped protrusion structure, the number of micro-mixing units in series is reduced, the length of the overall flow channel is shortened, and efficient mixing of microfluidics is achieved with less volume usage, thereby effectively reducing the consumption of reagents.

[0005] According to a first aspect of the present application, an enhanced micro-hybrid unit is provided, the enhanced micro-hybrid unit comprising: A mixing chamber surrounded by an upper wall, a lower wall and symmetrically arranged side walls for mixing and circulating feed liquids, wherein two ends of the mixing chamber along the flow direction of the feed liquid are a mixing chamber inlet and a mixing chamber outlet respectively; The mixing chamber includes a flow disturbance structure, which includes a fan-shaped retaining wall perpendicular to the flow direction of the liquid and at least one pair of L-shaped protrusions; The fan-shaped baffle wall is a protrusion formed on the upper wall and / or lower wall of the mixing chamber, and the fan-shaped baffle wall divides the mixing chamber into a symmetrical first flow channel and a second flow channel; when the thickness of the protrusion or the sum of the protrusions of the upper and lower walls is equal to the depth of the mixing chamber, the upper end surface of the fan-shaped baffle wall is tightly connected to the upper wall of the mixing chamber (integrally formed), and the lower end surface of the fan-shaped baffle wall is tightly connected to the lower wall of the mixing chamber (integrally formed).

[0006] The two ends of the first flow channel and the second flow channel meet at the mixing chamber inlet and the mixing chamber outlet respectively; The L-shaped protrusions are protrusions formed on the upper wall and / or the lower wall of the mixing chamber, and each pair of the L-shaped protrusions are symmetrically arranged in the first flow channel and the second flow channel; The L-shaped inflection point of the spoiler structure faces the inlet direction of the mixing chamber.

[0007] In the present application, the meaning of the fan-shaped retaining wall refers to a broad fan-shaped, also called a curved triangle, that is, the arc edge of the fan and the two sides of the fan can be partial arcs and radii of the same circle, or partial arcs and radii of different circles.

[0008] Optionally, the upper end surface and the lower end surface of the sector-shaped baffle wall are respectively connected to the upper wall and the lower wall of the mixing chamber, and the sector-shaped baffle wall divides the mixing chamber into a symmetrical first flow channel and a second flow channel.

[0009] Optionally, the enhanced micro-hybrid unit has one or more of the following features: The width of the mixing chamber inlet is 0.5-2 mm, and the depth is 0.5-2 mm; The width of the mixing chamber outlet is 0.5-2 mm, and the depth is 0.5-2 mm; The maximum width of the mixing chamber is 3-6 mm, the narrowest width is 0.5-2 mm, the depth is 0.5-2 mm, and the length is 8-10 mm; The height of the fan-shaped retaining wall is 0.5-2 mm, the radius of the curved surface of the fan-shaped retaining wall is 1.9-2 mm, the curved surface angle of the fan-shaped retaining wall is 100-140°, and the angular arc of the fan-shaped retaining wall is 40-80°; Optionally, the fan-shaped retaining wall is a block whose side is composed of two planes and one curved surface, and the angular arc of the fan-shaped retaining wall refers to the angle between the two planes of the fan-shaped baffle.

[0010] Optionally, the arc surface of the sector-shaped retaining wall faces the inflow direction of the mixed microfluid, and the vertex faces the outflow direction of the mixed microfluid.

[0011] The spacing between each pair of L-shaped protrusions is 0.2-0.4 mm, the width of the L-shaped protrusion is 0.1-0.2 mm, the height is 0.5-1 mm, the long side length of the L-shaped protrusion is 1.6-1.8 mm, and the short side length is 0.5-0.7 mm.

[0012] Optionally, the spoiler structure includes 1-3 pairs of L-shaped structures.

[0013] Optionally, the spoiler structure includes a first pair of L-shaped structures arranged between the mixing chamber inlet and the fan-shaped baffle wall and / or a second pair of L-shaped structures arranged between the mixing chamber outlet and the fan-shaped baffle wall; The short sides of the two L-shaped structures of the first pair of L-shaped structures are arranged opposite to each other, wherein the angle between the short side and the length direction of the mixing chamber is 40-50°, and the vertical distance between the L-shaped inflection point and the inlet end face of the mixing chamber is 0.4-0.6 mm; The long sides of the two L-shaped structures of the second pair of L-shaped structures are arranged opposite to each other, wherein the angle between the long side and the length direction of the mixing chamber is 50-60°, and the vertical distance between the L-shaped inflection point and the outlet end face of the mixing chamber is 3-4 mm.

[0014] Optionally, the vertical distance between the end surface of the sector-shaped baffle wall close to the mixing chamber inlet and the mixing chamber inlet is 2-3 mm.

[0015] Optionally, the side wall of the mixing chamber is an arc-shaped side wall, and the width of the mixing chamber is greater than the width of the mixing chamber inlet and the mixing chamber outlet; The mixing chamber is an elliptical portion perpendicular to the flow direction of the feed liquid, and the elliptical portion is a shape obtained by symmetrically removing the two end portions along the long axis direction of the ellipse; The major axis of the oval is 10-15 mm, and the minor axis is 3-6 mm.

[0016] According to a second aspect of the present application, a microfluidic mixer is provided, comprising: An inlet flow channel, at least one contraction-expansion mixing flow channel, and an outlet flow channel arranged in series; The inlet flow channel includes a converging flow channel, and at least two feed flow channels are provided at the inlet end of the converging flow channel; The contraction-expansion mixing channel includes one enhanced micro-mixing unit or at least two enhanced micro-mixing units arranged in series; Optionally, the series arrangement of the enhanced micro-mixing units means that two adjacent enhanced micro-mixing units are directly connected, that is, the mixing chamber outlet of the enhanced micro-mixing unit relatively close to the inlet flow channel is connected to the mixing chamber inlet of the adjacent enhanced micro-mixing unit relatively far from the inlet flow channel, and the enhanced micro-mixing units are arranged in parallel and in a straight line.

[0017] The enhanced micro-mixing unit is selected from the enhanced micro-mixing units mentioned above.

[0018] Optionally, the microfluidic mixer has one or more of the following features: The converging flow channel has a width of 0.5-2 mm, a length of 5-11 mm, and a depth of 0.5-2 mm; The width of each of the at least two feed channels is independently 0.5-2 mm, the length is independently 5-10 mm, and the depth is independently 0.5-2 mm; The outlet flow channel has a width of 0.5-2 mm, a length of 5-20 mm, and a depth of 0.5-2 mm; The contraction-expansion mixing channel includes 10-30 enhanced micro-mixing units arranged in series.

[0019] Optionally, the convergence-divergence mixing channel includes 10-15 enhanced micro-mixing units arranged in series.

[0020] Optionally, two feed channels are provided at the inlet end of the converging channel, namely a first feed channel and a second feed channel which are provided at an angle of 90°.

[0021] Optionally, the microfluidic mixer comprises: An inlet flow channel, at least two contraction-expansion mixing flow channels, and an outlet flow channel arranged in series; Adjacent contraction-expansion mixing channels are connected via turning channels; The turning channel has a width of 0.5-2 mm, a length of 5-20 mm, and a depth of 0.5-2 mm.

[0022] The length of the turning channel described in this application refers to the outer circle length of the turning channel.

[0023] Optionally, the turning channel is used to achieve the turning of the microfluidic mixer so that each contraction-expansion mixing channel is arranged in parallel.

[0024] Optionally, the enhanced micro-mixing unit or microfluidic mixer is manufactured by MEMS manufacturing process, 3D printing or mechanical processing process, and has an integrated structure.

[0025] According to a third aspect of the present application, an application of the above-mentioned microfluidic mixer is provided, and the application includes one of drug preparation research and development and continuous synthesis of new materials.

[0026] The drug preparation research and development is a drug or gene carrier selected from synthetic microcapsules, synthetic liposomes, and synthetic lipid nanoparticles; this application not only improves the bioavailability of the drug or gene, but also improves the efficiency and quality of preparation research and development.

[0027] The new material is continuously synthesized by synthesizing at least one nanomaterial selected from synthetic emulsion, synthetic hydrogel microspheres, and synthetic polymers. This application can not only realize the synthesis of nanoparticles of different particle sizes and shapes by controlling the flow rate and mixing conditions, but also improve production efficiency, reduce energy consumption, and realize sustainable development of material preparation.

[0028] The beneficial effects of this application include: The enhanced micro-mixing unit and microfluidic mixer provided by the present application utilize a contraction-expansion mixing unit to disrupt the laminar flow of the fluid, induce secondary flow and vortex, and promote mixing. The design of the fan-shaped baffle can cause multiple tangential mixing of the fluid to promote efficient mixing, and the L-shaped protrusion structure can further disturb the mixed microfluid to promote efficient mixing. By introducing an L-shaped structure, the present application reduces the number of micro-mixing units in series, shortens the length of the overall flow channel, and achieves efficient mixing of two microfluids with less volume, effectively reducing the consumption of reagents.

[0029] The microfluidic mixer described in the present application has a small inlet and outlet pressure drop, good stability, and is not prone to rupture of the mixer. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Schematic diagram of a two-dimensional microfluidic mixer in this application.

[0031] Figure 2 Schematic diagram of a three-dimensional microfluidic mixer in this application.

[0032] Figure 3 It is a two-dimensional schematic diagram of the micro-mixing unit in this application.

[0033] Figure 4 3D schematic diagram of the micro-mixing unit in this application.

[0034] Figure 5 This is a physical picture of the microfluidic mixer in this application.

[0035] Figure 6 This is a flow rate simulation diagram of the microfluidic mixer of Example 1 of the present application, wherein the vertical coordinates of the simulation diagram when Re=1 are all 0 because the speed is too low to be displayed in the software, rather than because the identification is incorrect.

[0036] Figure 7 This is a pressure simulation diagram of the microfluidic mixer of Example 1 of the present application.

[0037] Figure 8 1. The ethanol mass distribution cloud diagram (A is Re=1, B is Re=10, C is Re=50) and the mixing index diagram (D) of the cross-section of the microfluidic mixer at the outlet at different Reynolds numbers in the test example of the embodiment of the present application.

[0038] Fig. 9 This is a comparison diagram of the inlet and outlet pressure drops of the microfluidic mixer of Example 1 of the present application and the comparative example.

[0039] Attached Figure 1 The markings are as follows: 1 is a feed channel; 11 is a first feed channel; 12 is a second feed channel; 2 is a converging channel; 3 is a contraction-expansion mixing channel; 31 is an enhanced micro-mixing unit; 311 is a fan-shaped baffle; 312 is an L-shaped protrusion; 313 is a first channel; 314 is a second channel; 4 is a turning channel; 5 is an outlet channel; In the attached Figure 1 -Attached Figure 7 In the drawings, the same components are marked with the same reference numerals. DETAILED DESCRIPTION

[0040] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0041] Unless otherwise specified, the raw materials in the examples of this application were purchased through commercial channels.

[0042] Unless otherwise specified, conventional methods were used for testing and instrument settings were those recommended by the manufacturer.

[0043] According to one embodiment of the present application, the structural schematic diagram of the microfluidic mixer is as follows: Figure 1 , Figure 2 As shown, including: An inlet flow channel, at least one contraction-expansion mixing flow channel 3, and an outlet flow channel 5 arranged in series; When the number of the contraction-expansion mixing flow channels 3 is greater than 2, adjacent contraction-expansion mixing flow channels 3 are connected via the turning flow channels 4 .

[0044] The turning channel 4 is used to realize the turning of the microfluidic mixer so that each contraction-expansion mixing channel 3 is arranged in parallel.

[0045] The inlet flow channel includes a converging flow channel 2, and at least two feed flow channels 1 are provided at the inlet end of the converging flow channel 2; The contraction-expansion mixing channel 3 includes one enhanced micro-mixing unit 31 or at least two enhanced micro-mixing units 31 arranged in series; The series arrangement of the enhanced micro-mixing units 31 means that two adjacent enhanced micro-mixing units are directly connected, that is, the mixing chamber outlet of the enhanced micro-mixing unit relatively close to the inlet flow channel is connected to the mixing chamber inlet of the adjacent enhanced micro-mixing unit 31 relatively far from the inlet flow channel, and the enhanced micro-mixing units are arranged in parallel and in a straight line.

[0046] The structural schematic diagram of the enhanced micro-mixing unit 31 is as follows Figure 3 , Figure 4 As shown, including: A mixing chamber surrounded by an upper wall, a lower wall and symmetrically arranged side walls for mixing and circulating feed liquids, wherein two ends of the mixing chamber along the flow direction of the feed liquid are a mixing chamber inlet and a mixing chamber outlet respectively; The mixing chamber includes a flow disturbance structure, which includes a fan-shaped retaining wall 311 perpendicular to the flow direction of the liquid and at least one pair of L-shaped protrusions 312; The fan-shaped baffle wall 311 is a protrusion formed on the upper wall and / or lower wall of the mixing chamber, and the fan-shaped baffle wall divides the mixing chamber into a symmetrical first flow channel 313 and a second flow channel 314; when the thickness of the protrusion or the sum of the protrusions of the upper and lower walls is equal to the depth of the mixing chamber, the upper end surface of the fan-shaped baffle wall is tightly connected to the upper wall of the mixing chamber (integrally formed), and the lower end surface of the fan-shaped baffle wall is tightly connected to the lower wall of the mixing chamber (integrally formed).

[0047] The two ends of the first flow channel 313 and the second flow channel 314 meet at the mixing chamber inlet and the mixing chamber outlet respectively; The L-shaped protrusions 312 are protrusions formed on the upper wall and / or the lower wall of the mixing chamber, and each pair of the L-shaped protrusions 312 are symmetrically arranged in the first flow channel 313 and the second flow channel 314; The L-shaped inflection point of the spoiler structure faces the inlet direction of the mixing chamber.

[0048] In one embodiment, the upper end surface and the lower end surface of the sector-shaped retaining wall 311 are connected to the upper wall and the lower wall of the mixing chamber respectively, and the sector-shaped retaining wall 311 divides the mixing chamber into a symmetrical first flow channel 313 and a second flow channel 314 .

[0049] In one embodiment, the enhanced micro-mixing unit 31 or microfluidic mixer is manufactured by MEMS manufacturing process, 3D printing or mechanical processing process, and has an integrated structure.

[0050] In one embodiment, the converging flow channel 2 has a width of 0.5-2 mm, a length of 5-11 mm, and a depth of 0.5-2 mm.

[0051] In one embodiment, each of the at least two feed channels 1 has an independent width of 0.5-2 mm, an independent length of 5-10 mm, and an independent depth of 0.5-2 mm.

[0052] In one embodiment, two feed channels are disposed at the inlet end of the converging channel, namely a first feed channel and a second feed channel disposed at an angle of 90°.

[0053] In one embodiment, the outlet flow channel 5 has a width of 0.5-2 mm, a length of 5-20 mm, and a depth of 0.5-2 mm.

[0054] In one embodiment, the convergence-divergence mixing channel 3 includes 10-30 enhanced micro-mixing units 31 arranged in series.

[0055] In one embodiment, the inlet of the mixing chamber has a width of 0.5-2 mm and a depth of 0.5-2 mm.

[0056] In one embodiment, the width of the mixing chamber outlet is 0.5-2 mm, and the depth is 0.5-2 mm.

[0057] In one embodiment, the mixing chamber has a maximum width of 3-6 mm, a narrowest width of 0.5-2 mm, a depth of 0.5-2 mm, and a length of 8-10 mm.

[0058] In one embodiment, the width of the turning channel is 0.5-2 mm, the length is 5-20 mm, and the depth is 0.5-2 mm. In this embodiment, the length of the turning channel refers to the outer circle length of the turning channel.

[0059] In one embodiment, the height of the sector-shaped retaining wall 311 is 0.5-2 mm, the radius of the curved surface of the sector-shaped retaining wall 311 is 1.9-2 mm, the angle of the curved surface of the sector-shaped retaining wall 311 is 100-140°, and the angular arc of the sector-shaped retaining wall 311 is 40-80°.

[0060] In one embodiment, the fan-shaped retaining wall 311 is a block whose side is composed of two planes and one curved surface, and the angular arc of the fan-shaped retaining wall 311 refers to the angle between the two planes of the fan-shaped retaining wall.

[0061] In one embodiment, the arc surface of the sector-shaped retaining wall 311 faces the inflow direction of the mixed microfluid, and the vertex faces the outflow direction of the mixed microfluid.

[0062] In one embodiment, the spacing between each pair of L-shaped protrusions 312 is 0.2-0.4 mm, the width of the L-shaped protrusion 312 is 0.1-0.2 mm, the height is 0.5-1 mm, the long side length of the L-shaped protrusion 312 is 1.6-1.8 mm, and the short side length is 0.5-0.7 mm.

[0063] In one embodiment, the spoiler structure includes 1-3 pairs of L-shaped structures.

[0064] In one embodiment, the spoiler structure includes a first pair of L-shaped structures disposed between the mixing chamber inlet and the sector-shaped baffle wall 311 and / or a second pair of L-shaped structures disposed between the mixing chamber outlet and the sector-shaped baffle wall 311 .

[0065] In one embodiment, the short sides of the two L-shaped structures of the first pair of L-shaped structures are arranged opposite to each other, wherein the angle between the short side and the length direction of the mixing chamber is 40-50°, and the vertical distance between the L-shaped inflection point and the inlet end face of the mixing chamber is 0.4-0.6 mm.

[0066] In one embodiment, the long sides of the two L-shaped structures of the second pair of L-shaped structures are arranged opposite to each other, wherein the angle between the long side and the length direction of the mixing chamber is 50-60°, and the vertical distance between the L-shaped inflection point and the outlet end face of the mixing chamber is 3-4 mm.

[0067] In one embodiment, the vertical distance between the end surface of the sector-shaped baffle wall 311 close to the mixing chamber inlet and the mixing chamber inlet is 2-3 mm.

[0068] In one embodiment, the side wall of the mixing chamber is an arc-shaped side wall, and the width of the mixing chamber is greater than the width of the mixing chamber inlet and the mixing chamber outlet.

[0069] The mixing chamber is an elliptical portion perpendicular to the flow direction of the feed liquid, and the elliptical portion is a shape obtained by symmetrically removing the two end portions along the long axis direction of the ellipse; The major axis of the oval is 10-15 mm, and the minor axis is 3-6 mm. Example 1

[0070] The structure of the microfluidic mixer is as follows Figure 1 , Figure 2 As shown, it is composed of an inlet flow channel, two contraction-expansion mixing flow channels 3, and an outlet flow channel 5 arranged in series. Adjacent contraction-expansion mixing flow channels 3 are connected by a turning flow channel 4, and each contraction-expansion mixing flow channel 3 is arranged in parallel.

[0071] The inlet flow channel includes a converging flow channel 2, and the inlet end of the converging flow channel 2 is symmetrically provided with a first feed flow channel 11 and a second feed flow channel 12 along the length direction of the converging flow channel 2, and the angle between the first feed flow channel 11 and the second feed flow channel 12 is 90°; The contraction-expansion mixing channel 3 is a plurality of enhanced micro-mixing units 31 arranged in series; The enhanced micro-hybrid units are arranged in parallel and in a straight line, and the structure is as follows Figure 3 , Figure 4As shown, each enhanced micro-mixing unit 31 is composed of a mixing chamber for mixing and circulating feed and liquid, which is surrounded by an upper wall, a lower wall and symmetrically arranged side walls, and a spoiler structure arranged in the mixing chamber. The two ends of the mixing chamber along the flow direction of the feed and liquid are the mixing chamber inlet and the mixing chamber outlet respectively; the side wall of the mixing chamber is an arc-shaped side wall, and the width of the mixing chamber is greater than the width of the mixing chamber inlet and the mixing chamber outlet; the mixing chamber is an elliptical part perpendicular to the flow direction of the feed and liquid, and the elliptical part is a shape of symmetrically removing the two end parts along the long axis direction of the ellipse. The spoiler structure includes a fan-shaped fan-shaped baffle 311 perpendicular to the flow direction of the feed and liquid, and two pairs of L-shaped L-shaped protrusions 312; the fan-shaped baffle 311 is a protrusion formed on the lower wall of the mixing chamber, and the top surface of the protrusion is connected to the upper wall of the mixing chamber. The fan-shaped baffle 311 is a block composed of two planes and an arc surface on the side, and the angular arc of the fan-shaped baffle 311 refers to the angle between the two planes of the fan-shaped baffle. The arc surface of the fan-shaped baffle wall 311 faces the inflow direction of the mixed microfluid, and the vertex faces the outflow direction of the mixed microfluid. The fan-shaped baffle wall 311 divides the mixing chamber into a symmetrical first flow channel 313 and a second flow channel 314; the two ends of the first flow channel 313 and the second flow channel 314 respectively meet at the mixing chamber inlet and the mixing chamber outlet; the L-shaped protrusion 312 is a protrusion formed on the lower wall of the mixing chamber, and each pair of the L-shaped protrusions 312 is symmetrically arranged in the first flow channel 313 and the second flow channel 314, which are respectively a first pair of L-shaped structures arranged between the mixing chamber inlet and the fan-shaped baffle wall 311 and a second pair of L-shaped structures arranged between the mixing chamber outlet and the fan-shaped baffle wall 311, the short sides of the two L-shaped structures of the first pair of L-shaped structures are arranged opposite to each other, and the long sides of the two L-shaped structures of the second pair of L-shaped structures are arranged opposite to each other, and the L-shaped inflection point of the spoiler structure faces the mixing chamber inlet.

[0072] The enhanced micro-mixing unit 31 and the microfluidic mixer are manufactured by 3D printing technology and have an integrated structure. Figure 5 shown.

[0073] In this embodiment, the size parameters of each structural part in the microfluidic mixer are as follows: The first feed channel 11 and the second feed channel 12 have a width of 2 mm, a length of 10 mm, and a depth of 2 mm; The converging flow channel 2 has a width of 2 mm, a length of 11 mm, and a depth of 2 mm; Each of the contraction-expansion mixing channels 3 includes 12 enhanced micro-mixing units 31 arranged in series; The width of the turning channel 4 is 2 mm, the length is 17 mm (the length here refers to the outer circle length of the turning, which is 17 mm (arc radius 5.5 mm), and the inner circle length is 11 mm (arc radius 3.5 mm)), and the depth is 2 mm; The outlet flow channel 5 has a width of 2 mm, a length of 13 mm, and a depth of 2 mm; The width of the mixing chamber inlet is 2 mm and the depth is 2 mm; The width of the mixing chamber outlet is 2 mm and the depth is 2 mm; The mixing chamber has a maximum width of 6 mm, a narrowest width of 2 mm, a depth of 2 mm, and a length of 9.4 mm; The mixing chamber is an elliptical part, the major axis of the ellipse is 10 mm, and the minor axis is 6 mm; The height of the fan-shaped retaining wall 311 is 2 mm, the radius of the arc surface of the fan-shaped retaining wall 311 is 1.9 mm, the arc surface angle of the fan-shaped retaining wall 311 is 140°, and the angular arc of the fan-shaped retaining wall 311 is 50°; The vertical distance between the end surface of the fan-shaped baffle wall 311 close to the mixing chamber inlet and the mixing chamber inlet is 2.6 mm; The distance between each pair of L-shaped protrusions 312 is 0.38 mm, the width of the L-shaped protrusion 312 is 0.2 mm, the height is 1 mm, the long side length of the L-shaped protrusion 312 is 1.8 mm, and the short side length is 0.7 mm; The angle between the short side of the first pair of L-shaped structures and the length direction of the mixing chamber is 48°, and the vertical distance between the inflection point of the L-shaped structure and the inlet end face of the mixing chamber is 0.5 mm; The angle between the long side of the second pair of L-shaped structures and the length direction of the mixing chamber is 60°, and the vertical distance between the L-shaped inflection point and the outlet end face of the mixing chamber is 3.3 mm. Example 2

[0074] The structure of the microfluidic mixer is the same as that of Example 1, except that some structural dimension parameters of the microfluidic mixer are different, as follows: The first feed channel 11 and the second feed channel 12 have a width of 2 mm, a length of 10 mm, and a depth of 1 mm; The converging flow channel 2 has a width of 2 mm, a length of 11 mm, and a depth of 1 mm; Each of the contraction-expansion mixing channels 3 includes 12 enhanced micro-mixing units 31 arranged in series; The width of the turning channel 4 is 2 mm, the length is 17 mm (the length here refers to the outer circle length of the turning, which is 17 mm (arc radius 5.5 mm), and the inner circle length is 11 mm (arc radius 3.5 mm)), and the depth is 1 mm; The outlet flow channel 5 has a width of 2 mm, a length of 13 mm, and a depth of 1 mm; The width of the mixing chamber inlet is 2 mm and the depth is 1 mm; The width of the mixing chamber outlet is 2 mm and the depth is 1 mm; The mixing chamber has a maximum width of 6 mm, a narrowest width of 2 mm, a depth of 1 mm, and a length of 9.4 mm; The mixing chamber is an elliptical part, the major axis of the ellipse is 10 mm, and the minor axis is 6 mm; the height of the fan-shaped retaining wall 311 is 1 mm, the radius of the arc surface of the fan-shaped retaining wall 311 is 1.9 mm, the arc surface angle of the fan-shaped retaining wall 311 is 140°, and the angular arc of the fan-shaped retaining wall 311 is 50°; The vertical distance between the end surface of the fan-shaped baffle wall 311 close to the mixing chamber inlet and the mixing chamber inlet is 2.6 mm; The distance between each pair of L-shaped protrusions 312 is 0.38 mm, the width of the L-shaped protrusion 312 is 0.2 mm, the height is 0.5 mm, the long side length of the L-shaped protrusion 312 is 1.8 mm, and the short side length is 0.7 mm; The angle between the short side of the first pair of L-shaped structures and the length direction of the mixing chamber is 48°, and the vertical distance between the inflection point of the L-shaped structure and the inlet end face of the mixing chamber is 0.5 mm; The angle between the long side of the second pair of L-shaped structures and the length direction of the mixing chamber is 60°, and the vertical distance between the L-shaped inflection point and the outlet end face of the mixing chamber is 3.3 mm. Example 3

[0075] The structure of the microfluidic mixer is the same as that of Example 1, except that some structural dimension parameters of the microfluidic mixer are different, as follows: The first feed channel 11 and the second feed channel 12 have a width of 2 mm, a length of 10 mm, and a depth of 2 mm; The converging flow channel 2 has a width of 2 mm, a length of 11 mm, and a depth of 2 mm; Each of the contraction-expansion mixing channels 3 includes 12 enhanced micro-mixing units 31 arranged in series; The width of the turning channel 4 is 2 mm, the length is 17 mm (the length here refers to the outer circle length of the turning, which is 17 mm (arc radius 5.5 mm), and the inner circle length is 11 mm (arc radius 3.5 mm)), and the depth is 2 mm; The outlet flow channel 5 has a width of 2 mm, a length of 13 mm, and a depth of 2 mm; The width of the mixing chamber inlet is 2 mm and the depth is 2 mm; The width of the mixing chamber outlet is 2 mm and the depth is 2 mm; The mixing chamber has a maximum width of 6 mm, a narrowest width of 2 mm, a depth of 2 mm, and a length of 9.4 mm; The mixing chamber is an elliptical part, the major axis of the ellipse is 10 mm, and the minor axis is 6 mm; the height of the fan-shaped retaining wall 311 is 1 mm, the radius of the arc surface of the fan-shaped retaining wall 311 is 1.9 mm, the arc surface angle of the fan-shaped retaining wall 311 is 140°, and the angular arc of the fan-shaped retaining wall 311 is 50°; The vertical distance between the end surface of the fan-shaped baffle wall 311 close to the mixing chamber inlet and the mixing chamber inlet is 2.6 mm; The distance between each pair of L-shaped protrusions 312 is 0.38 mm, the width of the L-shaped protrusion 312 is 0.2 mm, the height is 0.5 mm, the long side length of the L-shaped protrusion 312 is 1.8 mm, and the short side length is 0.7 mm; The angle between the short side of the first pair of L-shaped structures and the length direction of the mixing chamber is 48°, and the vertical distance between the inflection point of the L-shaped structure and the inlet end face of the mixing chamber is 0.5 mm; The angle between the long side of the second pair of L-shaped structures and the length direction of the mixing chamber is 60°, and the vertical distance between the L-shaped inflection point and the outlet end face of the mixing chamber is 3.3 mm. Comparative Example 1

[0076] The structure of the microfluidic mixer of Comparative Example 1 refers to the patent design with publication number CN117732385A, and the same structure as Example 1 uses the same size parameters, except that the turbulent structure in the mixing chamber in the structure of Comparative Example 1 does not include an L-shaped protrusion. Test Case

[0077] Example 1 was used as a typical example to carry out flow velocity simulation and pressure simulation tests, and Comparative Example 1 was used as a control to test the comparison of the inlet and outlet pressure drops of the microfluidic mixer with and without the L-shaped protrusion. Specifically, SpaceClaim software was used to perform three-dimensional entity modeling of the microfluidic mixer, and ANSYS Meshing software was used to automatically mesh the three-dimensional model. Fluent software was used to perform numerical simulation of the mixed fluid in the microchannel. Without considering the effect of gravity, the laminar flow and material transfer modules were selected for numerical simulation. The velocity inlet boundary conditions were used at the two inlets of the micromixer, and the pressure outlet boundary conditions were used at the outlet. No-slip boundary conditions were used on all walls except the inlet and outlet. The density, dynamic viscosity and diffusion coefficient used in the simulation analysis were 1000kg / m 3 , 0.001Pa·s, 1×10 -11 m 2The mixed medium is anhydrous ethanol and deionized water, water flows into the first feed channel 11 and ethanol flows into the second feed channel 12. The mixing degree of the micro-mixing channel is usually expressed by the mass fraction of the ethanol component.

[0078] The specific liquid flow process is as follows: water enters the converging channel 2 through the first feed channel 11, ethanol enters the converging channel 2 through the second feed channel 12, water and ethanol flow in the converging channel 2 for preliminary mixing, the mixed medium continues to pass through the contraction-expansion mixing channel 3, and finally, the mixed microfluid of ethanol and water flows out of the microfluidic mixer through the outlet channel 5. In the contraction-expansion mixing channel 3, the fan-shaped baffle can cause multiple tangential mixing of the fluid, and the L-shaped protrusion structure can further disturb the mixed microfluid, accelerating the efficient mixing of water and ethanol.

[0079] The test results are as follows: like Figure 6 As shown in Figure 2, velocity simulation analysis of microfluidic mixer under different Reynolds numbers (Re). Figure 6 It can be seen that the flow rate of the mixed microfluid of water and ethanol is enhanced after meeting the fan-shaped baffle structure, which can generate vortices in the micro-mixing unit, promote rapid mixing between ethanol and water, and enhance the mass transfer effect; the flow rate of the mixed microfluid slows down after meeting the L-shaped convex structure, which can generate secondary flow at the right angle position of the L-shaped convex structure, accelerate the mixing between ethanol and water, and enhance the mass transfer effect. In addition, the mixed microfluid can be effectively squeezed and stretched in the contraction-expansion mixing channel, transforming from laminar flow to vortex, enhancing the collision between the mixed microfluids, and further promoting the mixing of microfluids.

[0080] like Figure 7 As shown in Figure 2, the pressure simulation analysis of the microfluidic mixer under different Reynolds numbers (Re). Figure 7 It can be seen that the pressure of the microfluidic mixer gradually decreases from the inlet to the outlet. As Re gradually increases, the inlet pressure of the microfluidic mixer gradually increases, but the pressure at the outlet eventually drops to the same level.

[0081] like Figure 8 As shown, the ethanol mass distribution cloud diagram and mixing index at the outlet of the microfluidic mixer under different Reynolds numbers (Re). Figure 8 AC is the ethanol mass distribution cloud at the outlet under various Re conditions. The results show that with the increase of Re, the change in the velocity of the two fluids will lead to unbalanced collision when ethanol and water are recombined, which in turn changes the contact area between the two and strengthens the mixing. Figure 8 D shows that the mixing index decreases first and then increases with the increase of Reynolds number. Among them, under the condition of Re being 50, the microfluidic mixer designed in this application can provide the most efficient mixing performance.

[0082] like Fig. 9As shown, under different Reynolds numbers (Re), the overall pressure drop comparison results of the microfluidic mixer designed in this patent and the microfluidic mixer of comparative example 1 are shown. The results show that with the increase of Re, the overall pressure drop of the microfluidic mixer is positively correlated with Re, and the overall pressure drop continues to increase with the increase of Re. In addition, under different Re conditions, the overall pressure drop of the microfluidic mixer of the present application is significantly lower than that of the microfluidic mixer of comparative example 1. The results show that the microfluidic mixer of the present application has better stability and is not easy to cause the mixer to rupture on the basis of providing efficient mixing function and reducing the amount of mixed fluid.

[0083] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. An enhanced micro-hybrid unit, characterized in that: The enhanced micro-hybrid unit comprises: A mixing chamber surrounded by an upper wall, a lower wall and symmetrically arranged side walls for mixing and circulating feed liquids, wherein two ends of the mixing chamber along the flow direction of the feed liquid are a mixing chamber inlet and a mixing chamber outlet respectively; The mixing chamber includes a flow disturbance structure, which includes a fan-shaped retaining wall perpendicular to the flow direction of the liquid and at least one pair of L-shaped protrusions; The fan-shaped baffle is a protrusion formed on the upper wall and / or the lower wall of the mixing chamber, and the fan-shaped baffle divides the mixing chamber into a symmetrical first flow channel and a second flow channel; The two ends of the first flow channel and the second flow channel meet at the mixing chamber inlet and the mixing chamber outlet respectively; The L-shaped protrusions are protrusions formed on the upper wall and / or the lower wall of the mixing chamber, and each pair of the L-shaped protrusions are symmetrically arranged in the first flow channel and the second flow channel; The L-shaped inflection point of the spoiler structure faces the inlet direction of the mixing chamber.

2. The enhanced micro-hybrid unit according to claim 1, characterized in that: The enhanced micro-hybrid unit has one or more of the following features: The width of the mixing chamber inlet is 0.5-2 mm, and the depth is 0.5-2 mm; The width of the mixing chamber outlet is 0.5-2 mm, and the depth is 0.5-2 mm; The maximum width of the mixing chamber is 3-6 mm, the narrowest width is 0.5-2 mm, the depth is 0.5-2 mm, and the length is 8-10 mm; The height of the fan-shaped retaining wall is 0.5-2 mm, the radius of the curved surface of the fan-shaped retaining wall is 1.9-2 mm, the curved surface angle of the fan-shaped retaining wall is 100-140°, and the angular arc of the fan-shaped retaining wall is 40-80°; The arc surface of the sector-shaped retaining wall faces the inflow direction of the mixed microfluid, and the vertex faces the outflow direction of the mixed microfluid; The spacing between each pair of L-shaped protrusions is 0.2-0.4 mm, the width of the L-shaped protrusion is 0.1-0.2 mm, the height is 0.5-1 mm, the long side length of the L-shaped protrusion is 1.6-1.8 mm, and the short side length is 0.5-0.7 mm.

3. The enhanced micro-hybrid unit according to claim 1, characterized in that: The spoiler structure includes 1-3 pairs of L-shaped structures.

4. The enhanced micro-hybrid unit according to claim 3, characterized in that: The flow-disturbing structure comprises a first pair of L-shaped structures arranged between the mixing chamber inlet and the fan-shaped baffle wall and / or a second pair of L-shaped structures arranged between the mixing chamber outlet and the fan-shaped baffle wall; The short sides of the two L-shaped structures of the first pair of L-shaped structures are arranged opposite to each other, wherein the angle between the short side and the length direction of the mixing chamber is 40-50°, and the vertical distance between the L-shaped inflection point and the inlet end face of the mixing chamber is 0.4-0.6 mm; The long sides of the two L-shaped structures of the second pair of L-shaped structures are arranged opposite to each other, wherein the angle between the long side and the length direction of the mixing chamber is 50-60°, and the vertical distance between the L-shaped inflection point and the outlet end face of the mixing chamber is 3-4 mm.

5. The enhanced micro-hybrid unit according to claim 1, characterized in that: The vertical distance between the end surface of the sector-shaped baffle wall close to the mixing chamber inlet and the mixing chamber inlet is 2-3 mm.

6. The enhanced micro-hybrid unit according to claim 1, characterized in that: The side wall of the mixing chamber is an arc-shaped side wall, and the width of the mixing chamber is greater than the width of the mixing chamber inlet and the mixing chamber outlet; The mixing chamber is an elliptical portion perpendicular to the flow direction of the feed liquid, and the elliptical portion is a shape obtained by symmetrically removing the two end portions along the long axis direction of the ellipse; The major axis of the oval is 10-15 mm, and the minor axis is 3-6 mm.

7. A microfluidic mixer, characterized in that: The microfluidic mixer comprises: An inlet flow channel, at least one contraction-expansion mixing flow channel, and an outlet flow channel arranged in series; The inlet flow channel includes a converging flow channel, and at least two feed flow channels are provided at the inlet end of the converging flow channel; The contraction-expansion mixing channel includes one enhanced micro-mixing unit or at least two enhanced micro-mixing units arranged in series; The enhanced micro-hybrid unit is selected from the enhanced micro-hybrid unit according to any one of claims 1 to 6.

8. The microfluidic mixer according to claim 7, characterized in that: The microfluidic mixer has one or more of the following features: The converging flow channel has a width of 0.5-2 mm, a length of 5-11 mm, and a depth of 0.5-2 mm; The width of each of the at least two feed channels is independently 0.5-2 mm, the length is independently 5-10 mm, and the depth is independently 0.5-2 mm; The outlet flow channel has a width of 0.5-2 mm, a length of 5-20 mm, and a depth of 0.5-2 mm; The contraction-expansion mixing channel includes 10-30 enhanced micro-mixing units arranged in series.

9. The microfluidic mixer according to claim 7, characterized in that: The microfluidic mixer comprises: An inlet flow channel, at least two contraction-expansion mixing flow channels, and an outlet flow channel arranged in series; Adjacent contraction-expansion mixing channels are connected via turning channels; The turning channel has a width of 0.5-2 mm, a length of 5-20 mm, and a depth of 0.5-2 mm.

10. Use of the microfluidic mixer according to any one of claims 7 to 9, characterized in that: The application includes one of the research and development of pharmaceutical preparations and continuous synthesis of new materials.

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