Disclosure of Invention
Based on the problems existing in the prior art, the invention aims to provide a micro-droplet active preparation device and method based on liquid drive flow focusing jet disturbance, which are used for preparing micro-droplets through active control.
The invention aims at realizing the following technical scheme:
the embodiment of the invention provides a micro-droplet active preparation device based on liquid drive flow focusing jet disturbance, which comprises the following components:
a piezoelectric device and a probe; wherein,,
the piezoelectric device is arranged above the jet flow column container, the probe is arranged on the piezoelectric device, the front end of the probe stretches into liquid in the jet flow column container and is positioned above the jet flow column in the jet flow column container, and the piezoelectric device can vibrate and drive the probe to vibrate to interfere with uncrushed jet flow column micro drops.
The embodiment of the invention also provides a micro-droplet active preparation method based on the disturbance of the liquid-driven flow focusing jet flow, which adopts the active preparation device provided by the invention and comprises the following steps:
the size and the generation frequency of micro liquid drops generated by the probe interfering with the breaking of the jet flow column are controlled by controlling the driving voltage, the driving frequency or the driving waveform of the piezoelectric device of the active preparation device, wherein the driving voltage is smaller than the breakdown voltage of the piezoelectric device, the driving frequency is the vibration frequency of the piezoelectric device and the probe in the liquid, and the driving waveform is any one of sine waves, square waves or saw-tooth waves.
According to the technical scheme provided by the invention, the micro-droplet active preparation device and method based on liquid-driven flow focusing jet disturbance provided by the embodiment of the invention have the beneficial effects that:
the disturbance process can be accurately controlled, and micro-droplets with required size and generation frequency can be conveniently prepared through active control.
Detailed Description
The following description of the embodiments of the present invention will clearly and fully describe the technical solutions of the embodiments of the present invention in conjunction with the specific contents of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to fall within the scope of the invention.
As shown in fig. 1, an active preparation device for micro-droplets based on disturbance of liquid-driven flow focusing jet flow according to an embodiment of the present invention can actively control preparation of micro-droplets, including:
a piezoelectric device and a probe; wherein,,
the piezoelectric device is arranged above the jet flow column container, the probe is arranged on the piezoelectric device, the front end of the probe stretches into liquid in the jet flow column container and is positioned above the jet flow column in the jet flow column container, and the piezoelectric device can vibrate and drive the probe to vibrate to interfere with uncrushed jet flow column micro drops. In the container with the structure, the jet flow column is formed by focusing based on liquid driving flow, driving liquid flows through the round hole from the driving liquid inlet, shearing force is provided for micro-droplet phases introduced by the needle tube to form a stable cone shape, the micro-droplet phases further pass through the round hole to form the jet flow column, and liquid in the container flows out through the outlet.
Referring to fig. 1, in the preparation apparatus, the piezoelectric device adopts a piezoelectric cantilever beam with one end fixed and the other end being a free end, the rear end of the probe is connected to the free end of the piezoelectric cantilever beam, and the specific probe is adhered near the free end of the piezoelectric cantilever beam.
Referring to fig. 4, in the above-mentioned preparation apparatus, the piezoelectric device is a piezoelectric simply supported beam with two fixed ends, and the rear end of the probe is connected to the middle part of the piezoelectric simply supported beam, which may specifically be disposed at the midpoint of the piezoelectric simply supported beam.
In the preparation device, the probe is made of an insulating material;
or the probe is made of insulating materials, the front end of the probe is provided with a circular opening (see figure 3) for the jet flow column to pass through, the jet flow column and the circular opening of the probe are concentric in the initial state, and the piezoelectric device drives the probe to disturb the jet flow column when vibrating.
In the above-mentioned preparation facilities, the jet column container includes:
the container body is provided with a driving liquid inlet at the upper end of the container body;
a droplet phase inlet arranged on the container body below the driving liquid inlet, a needle tube is arranged in the droplet phase inlet, the front end outlet of the needle tube corresponds to a round hole correspondingly arranged on the container body, and the needle tube can output liquid focused in the container body based on liquid driving flow to form a jet flow column;
and an outlet is correspondingly arranged on the container body behind the jet flow column.
In the preparation device, the needle tube is a single tube body or a coaxial wrapped tube body;
the container body adopts a transparent shell.
The embodiment of the invention provides a micro-droplet active preparation method based on liquid drive flow focusing jet disturbance, which adopts the active preparation device provided by the invention and comprises the following steps:
the size and the generation frequency of micro liquid drops generated by the probe interfering with the breaking of the jet flow column are controlled by controlling the driving voltage, the driving frequency or the driving waveform of the piezoelectric device of the active preparation device, wherein the driving voltage is smaller than the breakdown voltage of the piezoelectric device, the driving frequency is the vibration frequency of the piezoelectric device and the probe in the liquid, and the driving waveform is any one of sine waves, square waves or saw-tooth waves.
In the method, the micro-droplet phase can be formed by a core phase and a shell phase, the core phase can also be of a multi-core structure, further a jet column with a core-shell structure is formed, and the micro-droplet with the core-shell structure is formed through the disturbance of a piezoelectric device;
the preparation device provided by the invention has the advantages that the probe positioned right above the jet flow column is driven by the vibrating piezoelectric cantilever beam to interfere the uncrushed jet flow column to form micro-droplets, so that micro-droplets with uniform size and generation frequency required by preparation are actively controlled, the problems that the change amplitude of micro-droplets formed by controlling flow is limited, the flow is too large and too small, the taper shape with stable process is not easy to implement, the response time is long, usually a few seconds, the size uniformity of the generated micro-droplets is poor, satellite droplets are often accompanied, and the like are avoided.
Embodiments of the present invention are described in detail below.
As shown in fig. 1, the embodiment of the invention provides a micro-droplet active preparation device based on liquid-driven flow focusing jet disturbance, which mainly uses a piezoelectric cantilever beam 8 as a piezoelectric device to drive a probe 7 to interfere an uncrushed jet column 1, wherein the probe 7 on the piezoelectric cantilever beam 8 is positioned right above the jet column 1, and the probe 7 is adhered near the free end of the piezoelectric cantilever beam 8; the jet flow column 1 is formed by focusing based on liquid driving flow, driving liquid flows through the round hole 6 from the driving liquid inlet 5, a stable cone 4 is formed by providing shearing force for the micro-droplet phase 3 introduced by the needle tube 2, the micro-droplet phase 3 further passes through the round hole 6 to form the jet flow column 1, and liquid in the container 10 flows out through the outlet 9.
Only the probe 7 is stretched into the liquid, so that the insulation problem of the piezoelectric cantilever beam 8 is solved, and the liquid resistance is reduced.
When the electric cantilever beam 8 is not pressurized, the jet column 1 is prolonged under the liquid environment and is crushed due to surface tension, the size of the crushed liquid drops can be controlled only according to the flow, the response time is long, usually a few seconds, and the generated liquid drops are uneven in size and often occur with satellite liquid drops; when the piezoelectric cantilever beam 8 is pressurized to disturb, the vibration of the piezoelectric cantilever beam 8 drives the probe 7 to disturb the jet flow column 1, and the micro-droplet size and the generation frequency generated by the breaking of the jet flow column 1 are controlled by controlling the driving voltage, the driving frequency or the driving waveform of the piezoelectric cantilever beam 8.
As shown in fig. 2, the needle tube 2 may be two coaxial needle tubes, that is, the micro-droplet phase 3 may be formed by a core phase 31 and a shell phase 32, and the core phase 3-1 may be of a multi-core structure, so as to form a jet column with a core-shell structure, and the micro-droplet with the core-shell structure is formed by the disturbance of a piezoelectric cantilever beam.
As shown in fig. 3, the probe 7 may also have a circular opening 71, and in the initial state, the jet column 1 is concentric with the circular opening 71, and when the piezoelectric cantilever beam 8 vibrates, the probe 7 is driven to disturb the jet column 1.
As shown in fig. 4, the piezoelectric cantilever beam 8 as the piezoelectric device may be replaced by a piezoelectric simple beam 11, and the probe 7 is adhered to the middle point of the piezoelectric simple beam 11, so that the up-down swing of the probe 7 is purer.
The invention aims at the liquid-driven flow focusing device, introduces the energy of piezoelectric vibration after the jet flow column is formed, can intuitively and clearly observe the disturbance process, and prepares micro-droplets with required size and generation frequency by active control.
The foregoing is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions easily contemplated by those skilled in the art within the scope of the present invention should be included in the scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.