Apparatus and method for measuring drag force of nanoparticles by air flow

Abstract

The application provides a device and method for measuring the drag force of nanoparticles by airflow, and belongs to the field of nanoparticle monitoring. The device for measuring the drag force comprises a test chamber, an airflow generating component for sending supersaturated vapor airflow into the test chamber, a nanoparticle generating component for sending nanoparticles into the test chamber, a laser generating component for emitting first laser to the test chamber to generate an optical trap in the test chamber, the nanoparticles are suspended in the test chamber after being captured by the optical trap, the first laser forms second laser after passing through the nanoparticles, a detection component for determining the position of the nanoparticles according to the second laser, and a drag force determining component for determining the drag force of the supersaturated vapor airflow on the nanoparticles according to the position of the nanoparticles and the power of the first laser. The optical tweezer technology is used to non-contact capture the nanoparticles that occur heterogeneous condensation, the contact between the mechanical arm and the nanoparticles is avoided, and the measurement accuracy of the drag force of the airflow on the nanoparticles that occur heterogeneous condensation is improved.

Description

Technical Field

[0001] This invention relates to the field of nanoparticle monitoring, and in particular to a device and method for measuring the drag force of airflow on nanoparticles accompanied by heterogeneous condensation. Background Technology

[0002] Heterogeneous particle condensation is widespread in nature and industrial life. Nanoparticles accompanied by heterogeneous condensation are dragged by airflow during their movement with airflow. Since the interior of the nanoparticles accompanied by heterogeneous condensation is solid and the exterior is liquid, it is different from the drag force of traditional single-phase particles. Therefore, it is necessary to study the force and influencing factors of airflow on the nanoparticles that undergo heterogeneous condensation.

[0003] Traditional measurements of the force exerted by airflow on particles are based on nanorobotic arms. The nanorobotic arm manipulates the particles to a specific position, causing airflow to blow towards the particles at a specific speed and direction. Mechanical sensors placed on the robotic arm measure the force exerted by the robotic arm on the particles, and then analyze the drag force of the airflow on the particles.

[0004] However, this method is not suitable for measuring the force exerted by airflow on particles undergoing heterogeneous condensation. The reasons are as follows: First, the contact between the robotic arm and the particles affects the distribution of liquid outside the particles, thus affecting the drag force of the airflow on the particles. Second, the contact between the robotic arm and the particles prevents the airflow at the contact point from exerting a force on the particles, further affecting the measurement of the drag force. Therefore, nanorobotic arms cannot accurately measure the drag force of airflow on heterogeneous condensed nanoparticles. Summary of the Invention

[0005] The purpose of this invention is to provide a device and method for measuring the drag force of nanoparticles under airflow, which can improve the measurement accuracy of the drag force of heterogeneous condensed nanoparticles under airflow.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A device for measuring the drag force of nanoparticles under airflow, comprising:

[0008] Experimental chamber;

[0009] An airflow generating component, connected to the test chamber, is used to generate a supersaturated steam flow and send the supersaturated steam flow into the test chamber;

[0010] A nanoparticle generating component, connected to the test chamber, is used to generate nanoparticles and deliver the nanoparticles into the test chamber;

[0011] A laser generating component is disposed on one side of the test chamber and is used to emit a first laser into the test chamber to generate an optical trap within the test chamber; the nanoparticles in the test chamber are captured by the optical trap, causing the nanoparticles to suspend within the test chamber; the first laser passes through the nanoparticles and forms a second laser.

[0012] A detection component is disposed on the side of the test chamber opposite to the laser generating component, for detecting the second laser and determining the position of the nanoparticles in the test chamber based on the second laser.

[0013] The drag force determining component is connected to the detection component and the laser generating component respectively, and is used to determine the force exerted by the optical trap on the nanoparticle based on the position of the nanoparticle and the power of the first laser, so as to determine the drag force of the supersaturated steam flow on the nanoparticle.

[0014] Optionally, the airflow generating component includes:

[0015] Gas storage tanks are used to store supersaturated steam.

[0016] A flow meter, connected to the gas storage tank, is used to control the speed of the supersaturated steam flow.

[0017] An air delivery pipeline is connected to the flow meter and the test chamber respectively, and is used to deliver supersaturated steam gas flow into the test chamber.

[0018] Optionally, the airflow generating component further includes:

[0019] A temperature-controlled water bath is connected to the gas storage tank and is used to control the temperature inside the gas storage tank.

[0020] Optionally, the airflow generating component further includes:

[0021] A humidity controller, connected to the gas storage tank, is used to control the humidity inside the gas storage tank.

[0022] Optionally, the airflow generating component further includes:

[0023] An air compressor, connected to the air storage tank, is used to compress air and deliver the compressed air to the air storage tank to control the pressure of the supersaturated vapor in the air storage tank.

[0024] Optionally, the nanoparticle generating component includes:

[0025] Aerosol generators are used to produce nanoparticles;

[0026] The particle delivery pipeline is connected to both the aerosol generator and the test chamber, and is used to deliver the nanoparticles into the test chamber.

[0027] Optionally, the laser generating component includes:

[0028] A laser, used to generate the first laser beam;

[0029] A laser controller, connected to the laser, is used to control the wavelength and power of the first laser.

[0030] A microscope objective is placed in the optical path of the first laser to focus the first laser into the test chamber to form an optical trap.

[0031] Optionally, the detection component includes: a condenser lens, a lens, and a position detector;

[0032] The condenser lens is disposed on the side of the test chamber opposite to the laser generating component. The condenser lens is used to shape the second laser to obtain a shaped laser.

[0033] The lens is disposed in the optical path of the shaping laser, and the lens is used to focus the shaping laser onto the surface of the position detector;

[0034] The position detector is used to detect the position information of micro- and nano-particles.

[0035] Optionally, the device for measuring the drag force of the nanoparticles under airflow further includes:

[0036] A microscope is used to observe the particle size changes of micro- and nano-particles and the distribution characteristics of the outer liquid in the test chamber under the action of supersaturated steam flow.

[0037] To achieve the above objectives, the present invention also provides the following solution:

[0038] A method for measuring the drag force of nanoparticles on airflow, comprising:

[0039] Supersaturated steam flow is delivered into the test chamber via airflow generating components;

[0040] Nanoparticles are generated by a nanoparticle generating component and then delivered into the test chamber.

[0041] A first laser is emitted into the test chamber through a laser generating component to create an optical trap within the test chamber; nanoparticles are captured by the optical trap, causing the nanoparticles to suspend within the test chamber; the first laser then passes through the nanoparticles to form a second laser.

[0042] The location of nanoparticles inside the test chamber is detected in real time using a detection component.

[0043] The drag force determining component determines the force exerted by the optical trap on the nanoparticles based on the position of the nanoparticles and the power of the first laser, thereby determining the drag force of the supersaturated steam flow on the nanoparticles.

[0044] According to specific embodiments provided by the present invention, the following technical effects are disclosed: An airflow generating component delivers supersaturated steam gas into the test chamber; a nanoparticle generating component delivers nanoparticles into the test chamber; a laser generating component emits a first laser beam into the test chamber to create an optical trap within the chamber; the nanoparticles within the test chamber are captured by the optical trap, causing them to suspend; the first laser beam passes through the nanoparticles to form a second laser beam; a detection component detects the second laser beam and determines the position of the nanoparticles within the test chamber based on it; a drag force determining component determines the force exerted by the optical trap on the nanoparticles based on the position of the nanoparticles and the power of the first laser beam, thereby determining the drag force of the supersaturated steam gas flow on the nanoparticles. Using optical tweezers technology for non-contact capture of heterogeneously condensed nanoparticles avoids contact between the robotic arm and the nanoparticles, thereby improving the measurement accuracy of the drag force of the airflow on heterogeneously condensed nanoparticles. Attached Figure Description

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0046] Figure 1 This is a schematic diagram of the structure of the nanoparticle drag force measuring device of the present invention.

[0047] Figure 2 This is a flowchart of the method for measuring the drag force of nanoparticles under airflow according to the present invention.

[0048] Symbol explanation:

[0049] Test chamber-1, airflow generating component-2, air compressor-21, temperature-controlled water bath-22, humidity controller-23, air storage tank-24, flow meter-25, air delivery pipe-26, nanoparticle generating component-3, aerosol generator-31, particle delivery pipe-32, laser generating component-4, laser controller-41, laser-42, beam expander-43, first dichroic beam splitter-44, microscope objective-45, detection component-5, condenser lens-51, second dichroic beam splitter-52, lens-53, position detector-54, microscope-6, illumination source-7, illumination beam-8, nanoparticles-9. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] The purpose of this invention is to provide a device and method for measuring the drag force of nanoparticles under airflow. The device uses optical tweezers technology to capture heterogeneous condensed nanoparticles non-contactly, avoiding contact between the robotic arm and the particles, thereby improving the measurement accuracy of the drag force of airflow on heterogeneous condensed nanoparticles.

[0052] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0053] Example 1

[0054] like Figure 1 As shown, the device for measuring the drag force of nanoparticles under airflow according to the present invention includes: a test chamber 1, an airflow generating component 2, a nanoparticle generating component 3, a laser generating component 4, a detection component 5, and a drag force determining component.

[0055] The airflow generating component 2 is connected to the test chamber 1. The airflow generating component 2 is used to generate supersaturated steam flow and send the supersaturated steam flow into the test chamber 1.

[0056] Specifically, the airflow generating component 2 includes: a gas storage tank 24, a flow meter 25, and an air delivery pipe 26. The gas storage tank 24 is used to store supersaturated steam. The flow meter 25 is connected to the gas storage tank 24 and is used to control the speed of the supersaturated steam flow. The air delivery pipe 26 is connected to both the flow meter 25 and the test chamber 1, and is used to deliver the supersaturated steam flow into the test chamber 1. In this embodiment, the flow meter 25 is a high-precision moisture-resistant flow meter. The air delivery pipe 26 is a moisture-resistant air delivery pipe.

[0057] Furthermore, the airflow generating component 2 also includes a temperature-controlled water bath 22, a humidity controller 23, and an air compressor 21. The temperature-controlled water bath 22 is connected to the gas storage tank 24 and is used to control the temperature inside the gas storage tank 24. The humidity controller 23 is connected to the gas storage tank 24 and is used to control the humidity inside the gas storage tank 24. The air compressor 21 is connected to the gas storage tank 24 and is used to compress air and deliver the compressed air to the gas storage tank 24 to control the pressure of the supersaturated vapor inside the gas storage tank 24.

[0058] In this embodiment, the gas storage tank 24 is a moisture-resistant gas storage tank that stores supersaturated steam at a specific temperature, pressure, and humidity. The temperature-controlled water bath 22 is a high-precision temperature-controlled water bath. The humidity controller 23 is a high-precision humidity controller. Under the action of the air compressor 21, the temperature-controlled water bath 22, and the humidity controller 23, the gas storage tank 24 generates supersaturated steam at a specific pressure, temperature, and humidity. Under the control of the flow meter 25, the supersaturated steam enters the test chamber 1 at a certain speed through the air delivery pipe 26.

[0059] The nanoparticle generating component 3 is connected to the test chamber 1. The nanoparticle generating component 3 is used to generate nanoparticles and send the nanoparticles into the test chamber 1.

[0060] Specifically, the nanoparticle generating component 3 includes an aerosol generator 31 and a particle delivery pipe 32. The aerosol generator 31 is used to generate aerosol nanoparticles of a specific size and material. The particle delivery pipe 32 is connected to both the aerosol generator 31 and the test chamber 1, and is used to deliver the nanoparticles into the test chamber 1. In this embodiment, the particle delivery pipe 32 is an anti-particle adhesion pipe.

[0061] The nanoparticles generated by the aerosol generator 31 enter the test chamber 1 through the anti-particle adhesion pipe. The nanoparticles move with the airflow in the test chamber 1 and undergo heterogeneous condensation. They are captured when passing through the optical trap.

[0062] A laser generating component 4 is disposed on one side of the test chamber 1. The laser generating component 4 is used to emit a first laser beam into the test chamber 1 to generate an optical trap within the test chamber. The nanoparticles 9 within the test chamber 1 are captured by the optical trap, causing the nanoparticles 9 to suspend within the test chamber 1. The first laser beam passes through the nanoparticles and then forms a second laser beam.

[0063] Specifically, the laser generating component 4 includes a laser 42, a laser controller 41, and a microscope objective 45. The laser 42 generates a first laser beam. The laser controller 41 is connected to the laser 42 and controls the wavelength and power of the first laser beam. The microscope objective 45 is positioned in the optical path of the first laser beam and focuses the first laser beam into the test chamber 1 to form an optical trap.

[0064] Furthermore, the laser generating component 4 also includes a beam expander 43. The beam expander 43 is disposed between the laser 42 and the microscope objective 45, and is located in the optical path of the first laser. The beam expander 43 is used to expand the first laser beam.

[0065] Furthermore, when the laser 42 and the microscope objective 45 are not on the same straight line, the laser generating component 4 also includes a first dichroic beam splitter 44. The first dichroic beam splitter 44 is disposed between the beam expander 43 and the microscope objective 45, and is used to adjust the direction of the first laser so that the first laser is transmitted to the microscope objective 45.

[0066] Under the control of the laser controller 41, the laser 42 generates two first laser beams with specific wavelengths and specific power. The two first laser beams are adjusted by the first dichroic beam splitter 44 and enter the microscope objective 45, converging at the center of the test chamber 1, and generating a light trap of a certain intensity at that position.

[0067] The detection component 5 is disposed on the side of the test chamber 1 opposite to the laser generating component 4. The detection component 5 is used to detect the second laser and determine the position of the nanoparticle in the test chamber 1 based on the second laser.

[0068] Specifically, the detection component 5 includes a condenser lens 51, a lens 53, and a position detector 54. The condenser lens 51 is disposed on the side of the test chamber 1 opposite to the laser generating component 4, and is used to shape the second laser beam to obtain a shaped laser beam. The lens 53 is disposed in the optical path of the shaped laser beam, and is used to focus the shaped laser beam onto the surface of the position detector 54. The position detector 54 is used to detect the position information of micro / nano particles. In this embodiment, the position detector 54 is a four-quadrant position detector.

[0069] Furthermore, when the condenser lens 51 and the lens 53 are not on the same straight line, the detection component 5 also includes a second dichroic beam splitter 52. The second dichroic beam splitter 52 is disposed between the condenser lens 51 and the lens 53, and is used to adjust the direction of the shaping laser so that the shaping laser is transmitted to the lens 53.

[0070] That is, the second laser enters the condenser lens 51, and the laser direction is adjusted by the second dichroic beam splitter 52 before entering the lens 53 and converging, and then it is detected by the four-quadrant position detector.

[0071] In this embodiment, the test chamber 1 has transparent walls on both sides corresponding to the laser generating component 4 and the detection component 5, so that the laser can enter the test chamber 1.

[0072] The drag force determining component is connected to the detection component 5 and the laser generating component 4 respectively. The drag force determining component is used to determine the force exerted by the optical trap on the nanoparticle based on the position of the nanoparticle and the power of the first laser, so as to determine the drag force of the supersaturated steam gas flow on the nanoparticle.

[0073] Furthermore, the device for measuring the drag force of nanoparticles under airflow in this invention also includes a microscope 6. The microscope 6 is used to observe the particle size changes of micro- and nanoparticles that undergo heterogeneous condensation under the action of supersaturated steam airflow in the test chamber 1, as well as the distribution characteristics of the outer liquid.

[0074] In this embodiment, microscope 6 is a high-speed microscopic observation microscope.

[0075] The drag measuring device also includes an illumination source 7. The illumination source 7 is located on the same side of the test chamber 1 as the detection component 5. The illumination source 7 is used to generate an illumination beam 8. The first dichroic beam splitter 44 and the second dichroic beam splitter 52 are also used to transmit the illumination beam 8 to facilitate observation by the microscope 6.

[0076] Specifically, the illumination beam 8 generated by the illumination source 7 passes through the second dichroic beam splitter 52, the condenser lens 51, the microscope objective lens 45, and the first dichroic beam splitter 44 to illuminate the microscope 6.

[0077] To overcome the influence of existing particle manipulation methods on the liquid distribution outside heterogeneous condensation nanoparticles, this invention employs optical tweezers technology to non-contactly capture heterogeneous condensation nanoparticles. Two first laser beams are focused to generate an optical trap of a certain intensity. Nanoparticles accompanying heterogeneous condensation near the optical trap, which move with the airflow, are bound under the action of optical pressure. The supersaturated steam flow exerts a certain drag force on the bound accompanying heterogeneous condensation nanoparticles. The force exerted by the optical trap on the nanoparticles by the optical tweezers varies with the drag force on the nanoparticles. The magnitude of the drag force is related to parameters such as airflow velocity, original particle size and density, and particle size and density after heterogeneous condensation. Therefore, by calculating the force exerted by the optical trap on the particles based on the magnetic scattering model, the drag force of the supersaturated steam flow on the accompanying heterogeneous condensation nanoparticles can be obtained.

[0078] like Figure 2 As shown, the method for measuring the drag force of nanoparticles under airflow according to the present invention includes:

[0079] S1: Supersaturated steam flow is delivered into the test chamber through the airflow generating component.

[0080] Specifically, under the action of an air compressor, a temperature-controlled water bath, and a high-precision humidity controller, the gas storage tank generates supersaturated steam with a certain pressure, temperature, and humidity. The supersaturated steam enters the test chamber at a certain speed under the control of a flow meter.

[0081] S2: Nanoparticles are generated by a nanoparticle generating component and then sent into the test chamber.

[0082] Specifically, an aerosol generator produces an airflow carrying nanoparticles of specific components and sizes, which are then delivered into the experimental chamber through an anti-particle adhesion pipe. The nanoparticles are surrounded by a supersaturated steam flow, where they undergo heterogeneous condensation, resulting in an increase in particle size.

[0083] S3: A first laser beam is emitted into the test chamber via a laser generating component to create an optical trap within the chamber. Nanoparticles are captured by the optical trap, causing them to suspend within the chamber. The first laser beam then passes through the nanoparticles to form a second laser beam.

[0084] Specifically, a laser positioned outside the test chamber generates a first laser beam with a specific wavelength and power under the control of a laser controller. After passing through a dichroic beam splitter, the first laser beam converges at the center of the test chamber via a microscope objective, creating a light trap of a certain intensity at that location. The laser wavelength is selected based on the particle composition and the composition of the coagulating medium, avoiding the absorption bands of the particles and the coagulating medium to prevent the laser from being absorbed by the particles and generating heat, which could lead to the evaporation of liquid on the particle surface.

[0085] When the heterogeneously condensed nanoparticles pass through the optical trap in the experimental chamber, they are captured by the optical trap due to the light pressure.

[0086] The aerosol generator is shut down, and the speed of the supersaturated steam flow is adjusted to subject the captured nanoparticles to the dynamic drag force of the supersaturated steam flow. During the condensation and growth process, the mass of the nanoparticles continuously increases. As the drag force of the supersaturated steam flow on the nanoparticles changes, the power of the first laser is adjusted by the laser controller to ensure the nanoparticles are continuously and stably captured.

[0087] S4: The position of nanoparticles in the test chamber is detected in real time by the detection component.

[0088] S5: The drag force determining component determines the force exerted by the optical trap on the nanoparticles based on the position of the nanoparticles and the power of the first laser, so as to determine the drag force of the supersaturated steam flow on the nanoparticles.

[0089] Specifically, based on data such as the power of the first laser, the intensity of the optical trap, and the position of the nanoparticles, the force exerted on the nanoparticles by the optical trap is calculated using a magnetic scattering model, thereby obtaining the drag force of the supersaturated steam flow on the accompanying heterogeneous condensed nanoparticles.

[0090] The specific calculation method is as follows:

[0091] The particle in the optical trap receives both scattering force and gradient force. The force exerted by the airflow on the particle is the difference between the light gradient force and the scattering force. Treating the particle as an electric dipole, and approximating that the electric field strength remains constant within the small space occupied by the particle, for a particle with diameter d, the scattering force F... scattIt can be represented as:

[0092]

[0093] Where I0 is the incident light intensity, n m Let be the refractive index of the medium surrounding the particle, and c be the speed of light in a vacuum. σ represents the scattering cross-section of the particle.

[0094]

[0095] Where m is the ratio of the particle's refractive index to the refractive index of the surrounding gas, and λ is the laser wavelength.

[0096] Gradient force F grad for:

[0097]

[0098] Where α is the polarizability of the particle:

[0099]

[0100] The drag force of the airflow on the particles is:

[0101] F = F grad -F satt .

[0102] In addition, drag force measurement methods also include:

[0103] S6: The particle size of nanoparticles and the distribution of liquid on the outer side under airflow, as observed in real time using a microscope.

[0104] S7: By changing the original size of the nanoparticles, the humidity and velocity of the supersaturated steam flow, etc., the influence of the supersaturated steam flow on the drag force of the nanoparticles accompanied by heterogeneous condensation under each parameter is determined.

[0105] This invention proposes a method for measuring the drag force of airflow on nanoparticles undergoing heterogeneous condensation, based on optical tweezers. An optical tweezers system creates an optical trap of a certain intensity within a test chamber, enabling non-contact capture of nanoparticles that are moving with the airflow and undergoing heterogeneous condensation. The laser power is dynamically adjusted according to the change in the drag force of the airflow on the particles. Based on a magnetic scattering model, the force exerted by the optical trap on the particles is calculated in real time, which is the drag force of the airflow on the particles. This method achieves non-contact measurement of the drag force of airflow on nanoparticles undergoing heterogeneous condensation, overcoming the problems of inaccurate drag force measurements caused by the influence of liquid distribution outside the particles and the drag force of the airflow on the particles in traditional methods.

[0106] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0107] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A device for measuring the drag force of nanoparticles under airflow, characterized in that, The device for measuring the drag force of the nanoparticles on the airflow includes: Experimental chamber; An airflow generating component, connected to the test chamber, is used to generate a supersaturated steam flow and send the supersaturated steam flow into the test chamber; A nanoparticle generating component, connected to the test chamber, is used to generate nanoparticles and deliver the nanoparticles into the test chamber; A laser generating component is disposed on one side of the test chamber and is used to emit a first laser into the test chamber to generate an optical trap within the test chamber; the nanoparticles in the test chamber are captured by the optical trap, causing the nanoparticles to suspend within the test chamber; the first laser passes through the nanoparticles and forms a second laser. A detection component is disposed on the side of the test chamber opposite to the laser generating component, for detecting the second laser and determining the position of the nanoparticles in the test chamber based on the second laser. The drag force determining component is connected to the detection component and the laser generating component respectively, and is used to determine the force exerted by the optical trap on the nanoparticle based on the position of the nanoparticle and the power of the first laser, so as to determine the drag force of the supersaturated steam gas flow on the nanoparticle.

2. The device for measuring the drag force of nanoparticles under airflow according to claim 1, characterized in that, The airflow generating component includes: Gas storage tanks are used to store supersaturated steam. A flow meter, connected to the gas storage tank, is used to control the speed of the supersaturated steam flow. An air delivery pipeline is connected to the flow meter and the test chamber respectively, and is used to deliver supersaturated steam gas flow into the test chamber.

3. The device for measuring the drag force of nanoparticles under airflow according to claim 2, characterized in that, The airflow generating component further includes: A temperature-controlled water bath is connected to the gas storage tank and is used to control the temperature inside the gas storage tank.

4. The device for measuring the drag force of nanoparticles under airflow according to claim 2, characterized in that, The airflow generating component further includes: A humidity controller, connected to the gas storage tank, is used to control the humidity inside the gas storage tank.

5. The device for measuring the drag force of nanoparticles under airflow according to claim 2, characterized in that, The airflow generating component further includes: An air compressor, connected to the air storage tank, is used to compress air and deliver the compressed air to the air storage tank to control the pressure of the supersaturated vapor in the air storage tank.

6. The device for measuring the drag force of nanoparticles under airflow according to claim 1, characterized in that, The nanoparticle generating component includes: Aerosol generators are used to produce nanoparticles; The particle delivery pipeline is connected to both the aerosol generator and the test chamber, and is used to deliver the nanoparticles into the test chamber.

7. The device for measuring the drag force of nanoparticles under airflow according to claim 1, characterized in that, The laser generating component includes: A laser, used to generate the first laser beam; A laser controller, connected to the laser, is used to control the wavelength and power of the first laser. A microscope objective is placed in the optical path of the first laser to focus the first laser into the test chamber to form an optical trap.

8. The device for measuring the drag force of nanoparticles under airflow according to claim 1, characterized in that, The detection components include: a condenser lens, a lens, and a position detector; The condenser lens is disposed on the side of the test chamber opposite to the laser generating component. The condenser lens is used to shape the second laser to obtain a shaped laser. The lens is disposed in the optical path of the shaping laser, and the lens is used to focus the shaping laser onto the surface of the position detector; The position detector is used to detect the position information of micro- and nano-particles.

9. The device for measuring the drag force of nanoparticles under airflow according to claim 1, characterized in that, The device for measuring the drag force of the nanoparticles by the airflow also includes: A microscope is used to observe the particle size changes of micro- and nano-particles and the distribution characteristics of the outer liquid in the test chamber under the action of supersaturated steam flow.

10. A method for measuring the drag force of nanoparticles under airflow, using the device for measuring the drag force of nanoparticles under airflow as described in any one of claims 1-9, characterized in that, The method for measuring the drag force of the nanoparticles on the airflow includes: Supersaturated steam flow is delivered into the test chamber via airflow generating components; Nanoparticles are generated by a nanoparticle generating component and then delivered into the test chamber. A first laser is emitted into the test chamber through a laser generating component to create an optical trap within the test chamber; nanoparticles are captured by the optical trap, causing the nanoparticles to suspend within the test chamber; the first laser then passes through the nanoparticles to form a second laser. The location of nanoparticles inside the test chamber is detected in real time using a detection component. The drag force determining component determines the force exerted by the optical trap on the nanoparticles based on the position of the nanoparticles and the power of the first laser, thereby determining the drag force of the supersaturated steam flow on the nanoparticles.

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