Multiphase composite micro-mixer combined with shunting device

Abstract

The utility model discloses a multiphase composite micro-mixer combined with a shunting device. The multiphase composite micro-mixer comprises a mixing chip, a cover plate and an electromagnetic micro-valve, the mixing chip is provided with a mixing flow channel, and the mixing flow channel comprises a liquid inlet, a shunting and manufacturing time difference area, a mixing area and a liquid outlet which are communicated in sequence; the shunting and manufacturing time difference area comprises a shunting narrow channel and a shunting wide channel, the inner diameter of the shunting narrow channel is smaller than that of the shunting wide channel, an input port of the shunting narrow channel is communicated with an input port of the shunting wide channel, and an output port of the shunting narrow channel is communicated with an output port of the shunting wide channel; the cover plate seals and covers the mixing flow channel; the electromagnetic micro valve is used for controlling the opening and closing of the liquid outlet; the multi-phase quantitative mixing device has the advantages of high reliability, high mixing efficiency, wide application range and capability of performing multi-phase and quantitative mixing, and can play a greater role in scientific research and social life.

Description

Technical Field

[0001] The utility model relates to the technical field of microfluidics, and in particular to a multiphase composite micro mixer combined with a flow dividing device. Background Art

[0002] The preparation of standard solutions is crucial in science and industry, serving a variety of purposes, including determining the concentration of other chemical substances, instrument calibration, quality control, and data comparison and calibration. However, current methods for preparing standard solutions present numerous challenges. Mechanical stirring is simple but time-consuming, ultrasonic treatment is costly and can affect the solution and solutes, and magnetic stirring is unsuitable for high-viscosity liquids.

[0003] In addition, making all solutions reach the same concentration is also a big problem. In the dissolution process, there is the concept of an effective boundary layer. If a solid can dissolve in a liquid, and if there is no flow of fluid, the dissolution of the solid will be carried out by the diffusion of molecules. The diffusion process establishes a concentration gradient inside the fluid. As the diffusion time increases, the concentration gradient becomes smaller and the dissolution rate slows down. If convection occurs in the fluid, the dissolved substances will be continuously washed away by the fluid flowing over the surface. This scouring effect intensifies as the movement of the fluid accelerates. Obviously, the change in concentration gradient becomes steeper. Conventional treatment methods require dilution after calculating the ratio, and it takes time to make it reach the same concentration, which will take a lot of time in experimental research.

[0004] Microfluidics can effectively solve this problem. Microfluidics can achieve micron-scale fluid manipulation, and the process has a high degree of automation. The high-throughput characteristics can also greatly shorten the time required for reagent manufacturing.

[0005] Micromixers can be divided into passive micromixers and active micromixers according to the input energy. Current micromixers have the following disadvantages:

[0006] 1. Poor mixing effect: Under microscale conditions, fluid flow is mostly laminar. Under small Reynolds numbers (10 or even below 1), due to the small inertial force of the fluid, it is impossible to achieve a satisfactory mixing effect by relying solely on diffusion. However, the current research and design of micromixers for low Reynolds numbers is relatively insufficient.

[0007] 2. Limited usage scenarios: Most mixers can only mix two liquids with uniform concentrations, but cannot mix a liquid with uneven concentrations. They are also not suitable for scenarios where a small amount of liquid with a quantitative concentration needs to be taken.

[0008] 3. Complex structure and difficult processing: In order to improve the mixing effect, the structural design of some micromixers is relatively complex, such as having special geometric shapes, internal structures or micro-nanoscale features, which brings great challenges to manufacturing. It not only requires high-precision processing equipment and processes, but also increases manufacturing costs and time. Utility Model Content

[0009] The purpose of the utility model is to provide a multiphase composite micromixer combined with a diversion device, which has high reliability, high mixing efficiency, a wide range of applications, and the ability to perform multiphase and quantitative mixing, and can play a greater role in scientific research and social life.

[0010] In order to solve the above technical problems, the utility model provides a multi-phase composite micro-mixer combined with a diversion device, comprising a mixing chip, a cover plate and an electromagnetic microvalve; the mixing chip is provided with a mixing channel, and the mixing channel includes a liquid inlet, a diversion and time difference creating area, a mixing area and a liquid outlet connected in sequence; the diversion and time difference creating area includes a narrow diversion channel and a wide diversion channel, the inner diameter of the narrow diversion channel is smaller than the inner diameter of the wide diversion channel, the input port of the narrow diversion channel is connected to the input port of the wide diversion channel, and the output port of the narrow diversion channel is connected to the output port of the wide diversion channel; the cover plate seals and covers the mixing channel; the electromagnetic microvalve is used to control the opening and closing of the liquid outlet.

[0011] In one embodiment, the wide diversion channel includes a wide flow section and a narrow flow section that are connected to each other; the inner diameter of the wide flow section is larger than the inner diameter of the narrow flow section, and the input port of the wide flow section is connected to the input port of the narrow diversion channel; the output port of the narrow flow section is connected to the output port of the narrow diversion channel.

[0012] In one embodiment, the wide flow section, the narrow flow section and the narrow diversion channel form a triangle shape.

[0013] In one embodiment, the mixing region is a T-shaped square wave mixing channel.

[0014] In one embodiment, baffles are provided at multiple channel corners of the T-shaped square wave mixing channel.

[0015] In one embodiment, the cover plate is a glass cover plate.

[0016] In one embodiment, a valve groove is provided on the surface of the mixing chip facing away from the mixing channel, and the electromagnetic microvalve is provided in the valve groove.

[0017] In one embodiment, the electromagnetic microvalve is provided with a spring, and the spring is used to push the electromagnetic microvalve which is not energized to cover the liquid outlet.

[0018] The beneficial effects of the utility model are as follows:

[0019] 1. This multiphase composite micro mixer can quickly mix liquids with uneven concentrations in a single line, with high mixing efficiency and fast mixing speed.

[0020] 2. Combined with the high speed of electromagnetic microvalve, it can complete the concentration mixing of the predetermined mass or volume of the solution.

[0021] 3. The multiphase composite micro-mixer cleverly utilizes the baffle structure to reduce the space occupied by the chip. It has a sophisticated and simple structure, is easy to manufacture and install, and has modular characteristics, making it easy to integrate and apply. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for use in the implementation. Obviously, the drawings described below are only some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1 It is a structural diagram provided by an embodiment of the present utility model;

[0024] Figure 2 yes Figure 1 A schematic diagram of the enlarged structure of part A;

[0025] Figure 3 yes Figure 1 Schematic diagram of the mixing channel structure;

[0026] Figure 4 yes Figure 3 A schematic diagram of the enlarged structure of part B;

[0027] Figure 5 This is a diagram of the mixing effect of a T-shaped square wave mixing channel when no baffle is set;

[0028] Figure 6 This is the mixing effect diagram of the T-shaped square wave mixing channel after the baffle is set;

[0029] Figure 7 This is a simulation diagram provided by the utility model Figure 1 ;

[0030] Figure 8 This is a simulation diagram provided by the utility model Figure 2 ;

[0031] Figure 9 is the concentration surface plot;

[0032] Figure 10It is a concentration curve graph of the outlet fluid arc length in the range of 0-300um.

[0033] The reference numerals are as follows:

[0034] 10. Hybrid chip; 11. Valve slot;

[0035] 20. Cover plate;

[0036] 30. Solenoid microvalve; 31. Spring;

[0037] 40. Mixing channel; 41. Liquid inlet; 42. Diverter and time difference zone; 421. Diverter narrow channel; 422. Diverter wide channel; 4221. Wide flow section; 4222. Narrow flow section; 43. Mixing area; 431. Baffle; 44. Liquid outlet. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0039] The utility model provides a multiphase composite micro mixer combined with a flow dividing device, which is implemented as follows: Figures 1 to 4 As shown, it includes a mixing chip 10, a cover plate 20 and an electromagnetic microvalve 30; the mixing chip 10 is provided with a mixing channel 40, the mixing channel 40 includes a liquid inlet 41, a diversion and time difference making area 42, a mixing area 43 and a liquid outlet 44 connected in sequence; the diversion and time difference making area 42 includes a diversion narrow channel 421 and a diversion wide channel 422, the inner diameter of the diversion narrow channel 421 is smaller than the inner diameter of the diversion wide channel 422, the input port of the diversion narrow channel 421 is connected to the input port of the diversion wide channel 422, and the output port of the diversion narrow channel 421 is connected to the output port of the diversion wide channel 422; the cover plate 20 seals and covers the mixing channel 40, specifically, the cover plate 20 is a glass cover plate; the electromagnetic microvalve 30 is used to control the opening and closing of the liquid outlet 44.

[0040] During application, the substance to be dissolved can be pre-buried in the liquid inlet 41. Once the fluid is input, the fluid will flow through the diversion and create a time difference area 42. The liquid with the same concentration gradient will be diverted and flow into the diversion narrow channel 421 and the diversion wide channel 422. At this time, since the diversion wide channel 422 suddenly changes from narrow to wide, the flow rate of the fluid in the diversion wide channel 422 will slow down, that is, a time difference will be generated when the fluids in the diversion narrow channel 421 and the diversion wide channel 422 merge again, resulting in a time difference when the fluids merge again, resulting in the fluid concentration in the diversion narrow channel 421 being lower than the fluid concentration in the diversion wide channel 422, thereby achieving the purpose of mixing a section of uneven liquid front and back.

[0041] After the fluids are combined, they are mixed in the mixing area 43 . After the mixing is completed, the electromagnetic microvalve 30 only needs to be opened, and the mixed liquid can be output at the liquid outlet 44 .

[0042] like Figure 3 As shown, this embodiment provides a wide diversion channel 422 including a wide flow section 4221 and a narrow flow section 4222 that are connected to each other; the inner diameter of the wide flow section 4221 is larger than the inner diameter of the narrow flow section 4222, and the input port of the wide flow section 4221 is connected to the input port of the diversion narrow channel 421; the output port of the narrow flow section 4222 is connected to the output port of the diversion narrow channel 421; and at this time, the wide flow section 4221, the narrow flow section 4222 and the diversion narrow channel 421 form a triangle shape.

[0043] After adopting this arrangement, the arrangement area of ​​the wide diversion channel 422 can be increased within a limited space, so as to further improve the dissolution effect within the wide diversion channel 422 .

[0044] like Figures 1 to 3 As shown, in this embodiment, a valve slot 11 is provided on the surface of the mixing chip 10 facing away from the mixing channel 40, and an electromagnetic microvalve 30 is provided in the valve slot 11. The electromagnetic microvalve 30 is provided with a spring 31, which is used to push the unpowered electromagnetic microvalve 30 to block the liquid outlet 44.

[0045] After adopting this setting, when the electromagnetic microvalve 30 is not energized, the electromagnetic microvalve 30 will be subjected to a thrust due to the pre-tightening force generated by the spring 31, thereby blocking the liquid outlet 44; when the electromagnetic microvalve 30 is energized, the electromagnetic suction force generated by the electromagnetic microvalve 30 will overcome the elastic force of the spring 31, thereby placing the electromagnetic microvalve 30 in an open state, and the fluid can flow out smoothly through the liquid outlet 44.

[0046] like Figure 3 and Figure 4 As shown, in this embodiment, the mixing area 43 is configured as a T-shaped square wave mixing channel, and baffles 431 are provided at multiple channel corners of the T-shaped square wave mixing channel.

[0047] After adopting this configuration, the baffle 431 can enhance the vortex in the T-shaped square wave mixing channel, thereby enhancing the mixing effect.

[0048] for example Figure 5 This is a diagram showing the mixing effect of the T-shaped square wave mixing channel when the baffle 431 is not provided. Figure 6 The mixing effect diagram of the T-shaped square wave mixing channel after the baffle 431 is set. The two are simulated using comsol6.2. The simulation parameters are as follows: inlet flow velocity v = 0.03m / s, upper port concentration is 0mol / m 3 , the lower mouth concentration is 1 mol / m 3By comparison, it can be seen that the T-shaped square wave mixing channel after the baffle 431 is set can significantly improve the mixing efficiency.

[0049] Specifically, the present invention also provides theoretical explanation and simulation verification, as follows:

[0050] The fluid introduced into the liquid inlet 41 flows in the mixing channel 40 under the action of the air valve, dissolving the solute buried in the liquid inlet 41 area while flowing. Because there are more solutes at the beginning of dissolution, it is easy to form a saturated liquid. As time goes by, the solutes in the liquid inlet 41 area become less and less, and the contact with the fluid also decreases, causing the concentration of the fluid to begin to decrease, forming a phenomenon in which the concentration of the fluid entering the channel first is higher than that of the fluid at the rear end. The fluid with equal concentration terraces is divided into two after passing through the above-mentioned diversion and time difference area 42. Because the fluid in the wide diversion channel 422 has to flow through the time difference area, when the dissolved liquid in the narrow diversion channel 421 and the wide diversion channel 422 intersect, the front and back mixing of a single fluid with uneven concentration is achieved. After that, it enters the T-shaped square wave mixing channel provided with a baffle 431. The corner causes the fluid to produce vertical deflection. The liquid in the T-shaped square wave mixing channel is disturbed, forming a significant secondary flow, and the mixing effect is enhanced. Because of the presence of the baffle 431, the fluid flows through the gap between the baffle 431 and the tube wall at a faster speed, and a larger centrifugal force is generated at the same time. Under the action of the centrifugal force, the fluid flowing through the baffle 431 generates an expansion vortex in the flow channel behind the baffle 431, and the fluid is disturbed again, and the mixing effect is further enhanced.

[0051] Comsol 6.2 was used to predict the fluid streamlines in the entire flow channel and to calculate the fluid velocity in the plane. Since this chip was designed to meet the requirements of micro-quantitative sampling, the concentration of the fluid within the linear length of 0-300 μm at the outlet was calculated. The computational fluid dynamics software is based on finite elements. The simulation conditions are to set the circular area and the linear structure area as two-dimensional, the fluid is water with segmented concentration, and the concentration from 0 to 3s is 5 mol / m 3 , 3-10s is (6.5-0.5*t)mol / m 3 The geometric dimensions of the above flow channels are all in the micron order, and the numerical model uses the continuity equation, the viscous incompressible Navier-Stokes equation and the convection-diffusion equation.

[0052] The continuity equation is:

[0053] ▽u=0

[0054] The viscous incompressible Navier-Stokes equations are:

[0055] The convection-diffusion equation is:

[0056] Where u is the velocity vector of the fluid, ρ is the fluid density, v is the kinematic viscosity of the fluid, t is the time, p is the fluid pressure, c is the molar concentration of the component, and D is the diffusion coefficient of the component.

[0057] In addition to the basic fluid mechanics analysis equations mentioned above, the Reynolds number (Re) can reflect the motion state of the fluid and is used to analyze the mixing performance of the fluid. It has great reference value for the design of flow channel dimensions, the estimation of inflow velocity, and the comparison of mixing efficiency. Its mathematical definition is:

[0058] During the simulation, the inner wall of the channel was set to a non-slip boundary condition, the outlet was not set to pressure, and the fluid temperature was 298.15K.

[0059] From the simulation results, we can see that the mixing effect is good, the error is small, and the efficiency is high. The structural device is fully feasible, as follows Figures 7 to 10 shown.

[0060] like Figure 9 As shown, by observing the concentration surface graph, it can be seen that the color of the concentration graph when the liquid flows out of the liquid outlet 44 is almost the same.

[0061] like Figure 10 As shown in the figure, the concentration curve of the outlet fluid arc length in the range of 0-300um shows that the extreme value is less than 0.04mol / m 3 , the relative error is less than 1%, which shows that the mixing effect and efficiency are high.

[0062] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A multiphase composite micromixer combined with a diversion device, characterized in that: It includes a mixing chip, a cover plate and an electromagnetic microvalve; The mixing chip is provided with a mixing channel, which includes a liquid inlet, a diversion and time difference creation area, a mixing area, and a liquid outlet that are sequentially connected; the diversion and time difference creation area includes a narrow diversion channel and a wide diversion channel, the inner diameter of the narrow diversion channel is smaller than the inner diameter of the wide diversion channel, the input port of the narrow diversion channel is connected to the input port of the wide diversion channel, and the output port of the narrow diversion channel is connected to the output port of the wide diversion channel; The cover plate seals and covers the mixing channel; The electromagnetic microvalve is used to control the opening and closing of the liquid outlet.

2. The multiphase composite micromixer according to claim 1, characterized in that: The wide diversion channel includes a wide flow section and a narrow flow section connected to each other; The inner diameter of the wide flow section is larger than the inner diameter of the narrow flow section, and the input port of the wide flow section is connected to the input port of the diversion narrow channel; The output port of the narrow flow section is connected to the output port of the diversion narrow channel.

3. The multiphase composite micromixer according to claim 2, characterized in that: The wide flow section, the narrow flow section and the narrow diversion channel form a triangle shape.

4. The multiphase composite micromixer according to claim 1, characterized in that: The mixing region is a T-shaped square wave mixing channel.

5. The multiphase composite micromixer according to claim 4, characterized in that: Baffles are provided at multiple channel corners of the T-shaped square wave mixing channel.

6. The multiphase composite micromixer according to claim 1, characterized in that: The cover plate is a glass cover plate.

7. The multiphase composite micromixer according to claim 1, characterized in that: A valve slot is provided on the surface of the mixing chip facing away from the mixing channel, and the electromagnetic microvalve is provided in the valve slot.

8. The multiphase composite micromixer according to claim 7, characterized in that: The electromagnetic microvalve is provided with a spring, and the spring is used to push the electromagnetic microvalve which is not energized to cover the liquid outlet.

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