Mixed-phase ice crystal particle ground generation and icing experiment apparatus

Abstract

The utility model provides a kind of mixed phase ice crystal particle ground generation and icing experimental device, water droplet particle group is generated by water nozzle, ice crystal particle group is generated by ice crystal particle generation device, controllable proportion mixing is ice-water mixed phase, namely mixed phase icing experiment can be realized.The experimental device includes air duct system, water droplet atomization generation system, ice crystal particle generation system, impact surface system and measurement system;Air duct system includes axial flow fan, air duct and experimental cavity;Impact surface system includes impact surface assembly, water droplet atomization generation system and ice crystal particle generation system are respectively used to provide water droplet and ice crystal, axial flow fan provides high-speed airflow, water droplet and ice crystal are transported via air duct to high-speed impact impact surface assembly, and the impact of mixed phase is realized icing experiment;Measurement system is used to measure wind speed, temperature, humidity in air duct, and measure ice layer thickness, temperature to impact surface assembly.

Description

Technical Field

[0001] This invention relates to an experimental device for the generation and freezing of mixed-phase ice crystal particles on the ground. Background Technology

[0002] High-altitude ice crystals are a major cause of surge, shutdown, and even engine failure in commercial turbofan engines. After partial melting within the first few stages of the compressor, ice crystals form an "ice-water mixture," which, upon impacting the compressor blades, may either bounce off, break apart, or adhere to the airframe. Currently, there is no unified critical adhesion criterion, resulting in a lack of repeatable experimental evidence for airworthiness certification. While large facilities such as NASA-PSL and NRC-ICE-MACR have the capability to generate high-altitude ice crystals, their large size, high operating costs, and inability to independently adjust key parameters such as ice crystal size distribution, wet-bulb temperature, and impact kinetic energy make it difficult to systematically study the adhesion-icing coupling mechanism of ice crystal particle swarms.

[0003] Existing ice crystal experiments primarily focus on "single-particle impact on a static plate" or "continuous spray-wind tunnel icing," lacking ground-based facilities capable of simultaneously simulating "particle swarm-impacting surface-dynamic thermal environment." Due to the lack of controllable particle swarm generators, online synchronous measurement methods for particle size / velocity / temperature, and repeatable rapid de-icing / heating boundary conditions, the fragmentation, splashing, and refreezing processes of ice crystals within real compressor channels remain unmonitored quantitatively. Therefore, there is an urgent need for a ground-based ice crystal particle swarm experimental facility that can operate stably in a laboratory, with independently adjustable parameters, and capable of high spatiotemporal resolution measurements of the entire process from "generation-transport-impact-adhesion-icing," to support the development of airworthiness standards for engine ice crystal formation and the optimized design of anti-icing systems. Summary of the Invention

[0004] To address the problems existing in the background technology, this utility model proposes a mixed-phase ice crystal particle ground generation and icing experimental device. The entire device is placed in an environmental chamber with controllable ambient temperature and humidity to ensure that the entire experimental environment is adjustable and controllable. In the air duct, water droplet particle groups are generated by water nozzles, and ice crystal particle groups are generated by ice crystal particle generation devices. The two are mixed in a controllable ratio to form an ice-water mixed phase, which can realize the mixed-phase icing experiment.

[0005] The technical solution of this utility model to solve the above problems is:

[0006] This invention proposes an experimental device for ground generation and icing of mixed-phase ice crystal particles, which is characterized by including a wind duct system, a water droplet atomization generation system, an ice crystal particle generation system, an impact surface system, and a measurement system; the wind duct system, the water droplet atomization generation system, the ice crystal particle generation system, the impact surface system, and the measurement system are located inside a constant temperature environment chamber.

[0007] The air duct system includes an axial flow fan, an air duct, and an experimental chamber; the axial flow fan and the experimental chamber are located at opposite ends of the air duct; the impact surface system is located inside the experimental chamber; the impact surface system includes impact surface components.

[0008] The ice crystal particle generation system includes a quick-freezing chamber, a liquid nitrogen source, and a high-pressure nitrogen source. The quick-freezing chamber is an insulated cavity. The liquid nitrogen source is connected to the interior of the quick-freezing chamber through a supply pipeline and a recovery pipeline, respectively, to inject liquid nitrogen into the quick-freezing chamber and recover liquid nitrogen. The inlet of the recovery pipeline is connected to the bottom of the quick-freezing chamber, and a liquid nitrogen submersible pump is installed at the inlet of the liquid nitrogen submersible pump. A filter screen is installed at the inlet of the liquid nitrogen submersible pump. A replaceable gas-assisted atomizing water nozzle is installed in the upper part of the quick-freezing chamber. The gas-assisted atomizing water nozzle is connected to both the high-pressure nitrogen source and a water pipe through a pipeline. A liquid supply valve is installed on the water pipe. High-pressure nitrogen and water are delivered to the gas-assisted atomizing water nozzle. With the assistance of high-pressure nitrogen, the water sprayed from the gas-assisted atomizing water nozzle is atomized into a group of tiny water droplets. After entering the liquid nitrogen pool, the water droplets freeze rapidly to form a group of ice crystal particles.

[0009] The water droplet atomization generation system and the ice crystal particle generation system are used to provide water droplets and ice crystals, respectively. The axial flow fan provides high-speed airflow, which transports water droplets and ice crystals through the air duct to impact the surface components at high speed, realizing the impact icing experiment of the mixed phase. The measurement system is used to measure the wind speed, temperature and humidity in the air duct, as well as to measure the ice layer thickness and temperature of the impact surface components.

[0010] Furthermore, the aforementioned gas-assisted atomizing water nozzle is equipped with a heating structure to increase the temperature of the gas-assisted atomizing water nozzle and prevent the gas-assisted atomizing water nozzle from freezing due to excessively low local temperatures.

[0011] Furthermore, the heating structure described above includes a heating wire and a wire. The heating wire is wound around the outer layer of the gas-assisted atomizing water nozzle, and the heating wire is connected to a power source via the wire.

[0012] Furthermore, the bottom of the aforementioned quick-freezing chamber is equipped with a valve, and below the valve is a multi-layer vibrating screen to screen ice crystal particles.

[0013] Furthermore, the lower part of the above-mentioned multi-layer vibrating screen is provided with a movable sampling window, and the lower part of the movable sampling window is provided with a collection chamber. The bottom of the collection chamber is connected to a solenoid valve. By controlling the opening degree of the solenoid valve, the content of ice crystal particles conveyed into the pipeline can be controlled.

[0014] Furthermore, the aforementioned liquid supply pipeline is equipped with a low-temperature liquid supply valve, and the outlet of the liquid supply pipeline is connected to the middle of the quick-freezing chamber.

[0015] Furthermore, the above also includes a water storage tank and a water pump. The gas-assisted atomizing water nozzle is connected to the water pump through a pipe, and the water pump is located inside the water storage tank.

[0016] Furthermore, the liquid nitrogen source is a liquid nitrogen tank, which is positioned higher than the quick-freezing chamber. The high-pressure nitrogen source is a nitrogen cylinder, and a gas supply valve is provided on the pipe connecting the gas-assisted atomizing water nozzle and the high-pressure nitrogen source.

[0017] Furthermore, the aforementioned ice crystal particle cluster preparation device also includes a water storage tank and a water pump. The gas-assisted atomizing water nozzle is connected to the water pump through a pipe, and the water pump is located inside the water storage tank.

[0018] Furthermore, the aforementioned water droplet atomization generation system includes a gas-assisted atomizing water nozzle, which is connected to a water source and a high-pressure nitrogen source, respectively, and sprays out a group of tiny water droplet particles.

[0019] Furthermore, the aforementioned impact surface system includes an impact surface assembly and an impact angle control device; the impact surface assembly comprises a three-layer structure, consisting of a top aluminum plate, an adjustable constant heat flow heating film, and a bottom heat-insulating bakelite layer. The surface temperature of the top impact aluminum plate can be controlled by adjusting the voltage of the heating film.

[0020] Furthermore, the aforementioned measurement system includes two aspects: first, it uses temperature and humidity sensors and wind speed sensors installed in the air duct to measure the wind speed, temperature, and humidity inside the air duct; second, it uses a light source, a high-speed camera, and an infrared camera to measure the thickness and temperature of the ice layer on the impact surface components.

[0021] Advantages of this utility model:

[0022] 1. This utility model can achieve the large-scale, rapid, uniform and stable generation of ice crystal particle groups. It utilizes water spray to directly immerse and freeze in a liquid nitrogen pool, which can prepare a large number of ice crystal particles in a short time.

[0023] 2. Liquid nitrogen immersion freezing allows for the recovery and reuse of liquid nitrogen, making its operation more energy-efficient and environmentally friendly.

[0024] 3. This invention achieves controllable generation of ice crystal particle size distribution through two-stage control. The first stage utilizes the adjustment of the water nozzle model to achieve primary control over a large particle size range, while the second stage utilizes a multi-layer vibrating screen to achieve secondary control over the particle size distribution.

[0025] 4. This utility model can realize the sampling and measurement of ice crystal particle groups. By using the moving sampling window, ice crystal subgroups can be sampled and the particle size, quantity and shape of ice crystal particle groups can be measured.

[0026] 5. This utility model has high stability under extreme low-temperature conditions. It uses a heating wire to heat the water nozzle to prevent the nozzle from freezing at low temperatures.

[0027] 6. This utility model proposes a closed experimental device with adjustable and controllable experimental environment temperature, humidity and wind speed. It can be coupled with a water spray and ice crystal particle generation device to realize multi-condition freezing experiments of ice crystal particles / ice-water mixed phase.

[0028] 7. The experimental apparatus proposed in this utility model has adjustable and controllable icing conditions, and can strictly control icing conditions such as the content of ice crystal particles, liquid water content, and ice-water ratio in the airflow.

[0029] 8. The experimental device proposed in this utility model is a visualization experimental device that can directly observe various micro-dynamic behaviors of ice crystal particle groups, such as impact, adhesion, freezing and erosion.

[0030] 9. The experimental device proposed in this utility model has the functions of mixing, moving, colliding, adhering and freezing ice and water particles, and can realize basic research on various ice crystals.

[0031] 10. The experimental apparatus proposed in this utility model can realize the large-scale, rapid, continuous and stable generation of ice crystal particle groups. By using liquid nitrogen immersion to quickly freeze water spray, a large number of ice crystal particles can be prepared in a short time and long-term freezing experiment observation can be achieved. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the experimental device for ground generation and icing of mixed-phase ice crystal particles proposed in this utility model;

[0033] Figure 2 This is a schematic diagram of the ice crystal particle generation system;

[0034] Figure 3 This is a schematic diagram of the impact surface system.

[0035] Among them, 1-Quick freezing chamber, 2-Gas-assisted atomizing water nozzle, 3-Liquid supply pipeline, 4-Heating wire, 5-Power supply, 6-Valve, 7-Multi-layer vibrating screen, 8-Moving sampling window, 9-Collection chamber, 10-Recovery pipeline, 11-Gas supply valve, 12-Water storage tank, 13-Water pump, 14-Liquid nitrogen tank, 15-Nitrogen cylinder, 16-Liquid supply valve, 17-Axial flow fan, 18-Air duct, 19-Experimental chamber, 20-Impact surface assembly, 21-Top aluminum plate, 2 2-Heating film, 23-Bottom insulation bakelite, 24-Temperature and humidity sensor, 25-Wind speed sensor, 26-High-speed camera, 27-Infrared camera, 28-Water storage tank, 29-Submersible pump, 30-Control valve I, 31-Control valve II, 32-Control valve, 33-Solenoid valve, 34-Light source, 35-Impact angle control device, 37-Constant temperature environment chamber, 38-Fan frequency converter, 40-Liquid nitrogen submersible pump, 41-Filter screen, 42-Cryogenic supply valve. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Therefore, the following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely to represent selected embodiments of this utility model.

[0037] See Figure 1 This invention proposes an experimental device for the ground generation and icing of mixed-phase ice crystal particles, comprising a wind duct system, a water droplet atomization generation system, an ice crystal particle generation system, an impact surface system, and a measurement system. The wind duct system, water droplet atomization generation system, ice crystal particle generation system, impact surface system, and measurement system are located within a constant-temperature environmental chamber 37. The wind duct system includes an axial flow fan 17, a wind duct 18, a fan and frequency converter 38, and an experimental chamber 19. The axial flow fan 17 and the experimental chamber 19 are located at opposite ends of the wind duct 18. The wind duct is an open-loop system within the environmental chamber. The circulating airflow is controlled by the constant-temperature environmental chamber 37, and the impact wind speed is controlled by the fan and frequency converter 38. The impact surface system is located within the experimental chamber 19 and includes an impact surface assembly 20.

[0038] Specifically, see Figure 2 The ice crystal particle generation system includes a quick-freezing chamber 1, a liquid nitrogen source, and a high-pressure nitrogen source. The quick-freezing chamber 1 is a double-layered vacuum insulated cavity. The liquid nitrogen source is connected to the inside of the quick-freezing chamber 1 through a liquid supply pipeline 3 and a recovery pipeline 10. Liquid nitrogen is injected into the quick-freezing chamber 1 through the liquid supply pipeline 3 to form a liquid nitrogen pool, and liquid nitrogen is recovered from the quick-freezing chamber 1 through the recovery pipeline 10.

[0039] The upper part of the quick-freezing chamber 1 is equipped with replaceable gas-assisted atomizing water nozzles 2. These nozzles are connected to both a high-pressure nitrogen source and a water pipe via pipelines. A liquid supply valve is installed on the water pipe. Both high-pressure nitrogen and water are supplied to the gas-assisted atomizing water nozzles 2. With the assistance of high-pressure nitrogen, the water sprayed from the nozzles 2 is atomized into tiny water droplets. These droplets enter the liquid nitrogen pool and freeze rapidly, forming ice crystals. Due to the liquid nitrogen pool, the quick-freezing chamber 1 maintains a low-temperature environment, rapidly freezing the water droplets and preventing them from sticking together as they melt. By changing the type of gas-assisted atomizing water nozzle 2, nozzles 1 to 10... 2The wide particle size distribution of μm is controlled at the primary level. The inlet of the recovery pipeline 10 is connected to the bottom of the quick-freezing chamber 1, and a liquid nitrogen submersible pump 40 is provided at the inlet. A filter screen 41 is provided at the inlet of the liquid nitrogen submersible pump 40. The liquid nitrogen submersible pump 40 at the bottom of the quick-freezing chamber 1 is used to draw liquid nitrogen from the quick-freezing chamber 1. The filter screen 41 can prevent ice crystals from being drawn into the liquid nitrogen submersible pump 40 and causing blockage.

[0040] The water droplet atomization system and the ice crystal particle generation system provide water droplets and ice crystals to the air duct 18, respectively. The axial flow fan 17 provides high-speed airflow, which transports the water droplets and ice crystals through the air duct 18 to impact the surface component 20 at high speed, thereby realizing the impact icing experiment of the mixed phase. The measurement system is used to measure the wind speed, temperature and humidity in the air duct 18, as well as to measure the ice layer thickness and temperature of the impact surface component 20.

[0041] Specifically, see Figure 2 The liquid nitrogen source is a liquid nitrogen tank 14, the high-pressure nitrogen source is a nitrogen cylinder 15, and the gas-assisted atomizing water nozzle 2 is connected to the high-pressure nitrogen source through a pipeline, and the pipeline is equipped with a gas supply valve 11.

[0042] As a preferred embodiment of this utility model, see [link to relevant documentation]. Figure 2 The gas-assisted atomizing water nozzle is located in a low-temperature quick-freezing chamber. To prevent the nozzle from freezing, the gas-assisted atomizing water nozzle 2 is equipped with a heating structure. The heating structure increases the temperature of the gas-assisted atomizing water nozzle 2 and prevents the gas-assisted atomizing water nozzle 2 from freezing due to excessively low local temperature.

[0043] Specifically, the heating structure includes a heating wire 4, a wire, and a power supply. The heating wire 4 is wound around the outer layer of the gas-assisted atomizing water nozzle 2, and the heating wire 4 is connected to the power supply 5 through the wire, thereby appropriately increasing the temperature of the water spray. The power supply 5 is a DC power supply.

[0044] As a preferred embodiment of this utility model, see [link to relevant documentation]. Figure 2 The quick-freezing chamber 1 is equipped with a valve 6 at its bottom, and a multi-layer vibrating screen 7 is located below the valve 6 to screen ice crystal particles. By replacing the multi-layer vibrating screen, two-stage control of the ice crystal particle size can be achieved. A movable sampling window 8 is located at the lower part of the multi-layer vibrating screen 7, and a collection chamber 9 is located below the movable sampling window 8. The collection chamber 9 is a heat-insulated chamber, which can collect and store the generated ice crystal particles at a suitable temperature.

[0045] For example, by using a combination of 75-mesh and 150-mesh sieves, two-stage separation of ice crystal particle groups with a particle size distribution of 100-200μm can be achieved. A movable sampling window is installed below the vibrating screen, which can be opened to sample ice crystal particles, enabling sampling and detection of particle morphology, number, and size. The movable sampling window 8 is similar to a drawer structure, from which ice crystal particles can be extracted.

[0046] As a preferred embodiment of this utility model, see [link to relevant documentation]. Figure 2 The liquid nitrogen source is a liquid nitrogen tank 14, which is positioned higher than the quick-freezing chamber 1. The high-pressure nitrogen source is a nitrogen cylinder 15. The liquid supply pipeline 3 is equipped with a cryogenic liquid supply valve 42. The outlet of the liquid supply pipeline 3 is connected to the middle of the quick-freezing chamber 1, and the liquid nitrogen flows into the quick-freezing chamber 1 by gravity.

[0047] As a preferred embodiment of this utility model, see [link to relevant documentation]. Figure 2 The ice crystal particle generation system also includes a water storage tank 12 and a water pump 13. The gas-assisted atomizing water nozzle 2 is connected to the water pump 13 through a pipe. The water pump 13 is located inside the water storage tank 12. A liquid supply valve 16 is also connected to the pipe.

[0048] The working principle of the ice crystal particle generation system is as follows:

[0049] 1) Before starting the preparation, replace the corresponding gas-assisted atomizing water nozzles and multi-layer vibrating screens in advance according to the required ice crystal particle size and quantity;

[0050] 2) To prevent the gas-assisted atomizing water nozzle from freezing, first turn on the nozzle heating wire and adjust the heating voltage to make the nozzle temperature higher than the freezing point of water.

[0051] 3) Open the cryogenic liquid supply valve to supply liquid to the quick-freezing chamber, and use liquid nitrogen to pre-cool the quick-freezing chamber, screening and sampling window and collection chamber as a whole;

[0052] 4) Once the pre-cooling temperature is reached, turn on the water pump and nitrogen supply valve. The gas-assisted atomizing water nozzle will start working, generating a group of water droplets. After entering the liquid nitrogen pool, the water droplets will freeze rapidly, forming a group of ice crystals that fall to the bottom of the quick-freezing chamber.

[0053] 5) Once a sufficient number of ice crystal particles have been generated, close the gas supply valve and water pump, and turn on the liquid nitrogen submersible pump to recover the liquid nitrogen.

[0054] 6) Open the valve and use a multi-layer vibrating screen to screen the ice crystal particles; during the screening process, the shape and particle size of the ice crystals can be observed and sampled using a moving sampling window;

[0055] 7) Collect the ice crystal particle clusters and store them in the collection chamber for later use.

[0056] See Figure 1The water droplet atomization generation system includes a water tank 28, a submersible pump 29, water pipes, control valve I30, control valve II31, a nitrogen cylinder 15, a reversing valve 10, and gas-assisted atomizing water nozzles 2. The submersible pump 29 and control valve I30 work together to regulate the water supply, while the nitrogen cylinder 15 and control valve II31 regulate the nitrogen supply. When water droplet particles are needed, control valve I30 is opened, and the gas-assisted atomizing water nozzles 2 form a cluster of tiny water droplets. By changing the nozzle type, a wide particle size range can be controlled. When the gas-assisted atomizing water nozzles 2 are closed, control valve II31 is opened to introduce nitrogen, preventing the pipes from freezing and clogging. Control valve 32 can distribute and regulate the water volume of multiple gas-assisted atomizing water nozzles 2.

[0057] In this invention, the surface of the gas-assisted atomizing water nozzle 2 of the water droplet atomization generation system is also equipped with a heating wire, thereby appropriately increasing the temperature of the water spray and preventing the nozzle from freezing due to excessively low local temperatures.

[0058] Specifically, see Figure 1 The impact surface system includes an impact surface assembly 20 and an impact angle control device 35; see also Figure 3 The impact surface assembly 20 comprises a three-layer structure, consisting of a top aluminum plate 21, an adjustable constant heat flow heating film 22, and a bottom heat-insulating bakelite 23. The surface temperature of the top aluminum plate 21 can be controlled by adjusting the voltage of the heating film 22. The impact surface assembly 20 is located on the impact angle control device 35, which can control the rotation of the impact surface assembly 20.

[0059] Specifically, see Figure 1 The measurement system mainly includes two aspects: first, it uses the temperature and humidity sensor 24 and wind speed sensor 25 installed in the air duct 18 to measure the wind speed, wind temperature and humidity in the duct; second, it uses the light source 34, high-speed camera 26 and infrared camera 27 to measure the thickness and temperature of the ice layer on the impact surface.

[0060] This invention also proposes an experimental method for the impact, adhesion, freezing, and erosion of ice crystal particles / ice-water mixed phases. Based on the above-mentioned experimental apparatus for the ground generation and freezing of mixed phase ice crystal particles, the method mainly includes the following steps:

[0061] 1) Pre-open the constant temperature environment chamber 37 and set the preset environment temperature (the temperature is below 0 degrees Celsius, such as -5℃, to prevent ice crystal particles from melting);

[0062] 2) Turn on the axial flow fan (17), set the wind speed value, and run it continuously for more than 10 minutes to make the entire environment in the constant temperature environment chamber 37 reach a steady state.

[0063] 3) Turn on the ice crystal particle generation system to quickly prepare an appropriate amount of ice crystal particle clusters and store them in the collection chamber 9;

[0064] 4) Turn on the heating film 22 of the impact surface system and set the impact surface temperature;

[0065] 5) Start the measurement system and control the solenoid valve 33 to achieve uniform and stable delivery of ice particles into the pipeline and carry out ice crystal particle impact, adhesion and icing test.

[0066] 6) To conduct an ice-water mixed phase freezing experiment, ice particles need to be introduced while water spray is turned on, and the ice and water particles will be impacted and frozen in a certain proportion.

[0067] 7) By using a high-speed camera (26) and an infrared camera (27) to obtain information on the collision, adhesion, freezing and erosion of the top aluminum plate (21) of ice crystal particles / ice-water mixture, the freezing phenomenon and thermodynamic behavior can be observed.

[0068] The above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Those skilled in the art can still adjust the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Therefore, if these modifications and variations of the present utility model fall within the scope of the claims of the present utility model and their equivalents, the present utility model also intends to include these modifications and variations.

Claims

1. An experimental apparatus for the ground generation and icing of mixed-phase ice crystal particles, characterized in that: It includes an air duct system, a water droplet atomization generation system, an ice crystal particle generation system, an impact surface system, and a measurement system; the air duct system, the water droplet atomization generation system, the ice crystal particle generation system, the impact surface system, and the measurement system are located inside a constant temperature environment chamber (37); The air duct system includes an axial flow fan (17), an air duct (18), and an experimental chamber (19); the axial flow fan (17) and the experimental chamber (19) are located at opposite ends of the air duct (18); the impact surface system is located inside the experimental chamber (19); the impact surface system includes an impact surface assembly (20); The ice crystal particle generation system includes a quick-freezing chamber (1), a liquid nitrogen source, and a high-pressure nitrogen source; The quick-freezing chamber (1) is an insulated cavity. The liquid nitrogen source is connected to the inside of the quick-freezing chamber (1) through the liquid supply pipeline (3) and the recovery pipeline (10). The liquid supply pipeline (3) and the recovery pipeline (10) respectively realize the injection of liquid nitrogen into the quick-freezing chamber (1) and the recovery of liquid nitrogen. The inlet of the recovery pipeline (10) is connected to the bottom of the quick-freezing chamber (1), and a liquid nitrogen submersible pump (40) is provided at the inlet. The upper part of the quick-freezing chamber (1) is equipped with a replaceable gas-assisted atomizing water nozzle (2). The gas-assisted atomizing water nozzle (2) is connected to a high-pressure nitrogen source and a water pipe through a pipeline. A liquid supply valve (16) is provided on the water pipe. High-pressure nitrogen and water are transported to the gas-assisted atomizing water nozzle (2). With the assistance of high-pressure nitrogen, the water sprayed by the gas-assisted atomizing water nozzle (2) is atomized into liquid water to form a group of tiny water droplets. After the water droplet group enters the liquid nitrogen pool, it freezes rapidly to form a group of ice crystal particles. The water droplet atomization system and the ice crystal particle generation system provide water droplets and ice crystals to the air duct (18) respectively. The axial flow fan (17) provides high-speed airflow, which transports water droplets and ice crystals through the air duct (18) to impact the surface component (20) at high speed, thereby realizing the impact icing experiment of the mixed phase. The measurement system is used to measure the wind speed, temperature and humidity in the air duct (18), as well as to measure the ice layer thickness and temperature of the impact surface component (20).

2. The experimental apparatus for ground generation and icing of mixed-phase ice crystal particles according to claim 1, characterized in that: The gas-assisted atomizing water nozzle (2) is provided with a heating structure to increase the temperature of the gas-assisted atomizing water nozzle (2) and prevent the gas-assisted atomizing water nozzle (2) from freezing due to local low temperature.

3. The experimental apparatus for ground generation and icing of mixed-phase ice crystal particles according to claim 2, characterized in that: The heating structure includes a heating wire (4) and a wire. The heating wire (4) is wound around the outer layer of the gas-assisted atomizing water nozzle (2). The heating wire (4) is connected to a power source (5) through the wire.

4. The experimental apparatus for ground generation and icing of mixed-phase ice crystal particles according to claim 3, characterized in that: The quick-freezing chamber (1) is equipped with a valve (6) at the bottom, and a multi-layer vibrating screen (7) is provided below the valve (6) to screen ice crystal particles.

5. The experimental apparatus for ground generation and icing of mixed-phase ice crystal particles according to claim 4, characterized in that: The lower part of the multi-layer vibrating screen (7) is provided with a collection chamber (9), and the bottom of the collection chamber (9) is connected to a solenoid valve (33). By controlling the opening degree of the solenoid valve (33), the amount of ice crystal particles conveyed can be controlled.

6. The experimental apparatus for ground generation and icing of mixed-phase ice crystal particles according to claim 5, characterized in that: The liquid supply pipeline (3) is equipped with a low-temperature liquid supply valve (42), and the outlet of the liquid supply pipeline (3) is connected to the middle of the quick-freezing chamber (1); it also includes a water storage tank (12) and a water pump (13), and a gas-assisted atomizing water nozzle (2) is connected to the water pump (13) through a pipeline, and the water pump (13) is located in the water storage tank (12).

7. The experimental apparatus for ground generation and icing of mixed-phase ice crystal particles according to claim 6, characterized in that: The liquid nitrogen source is a liquid nitrogen tank (14), which is positioned higher than the quick-freezing chamber (1). The high-pressure nitrogen source is a nitrogen cylinder (15). A gas supply valve (11) is provided on the pipeline connecting the gas-assisted atomizing water nozzle (2) and the high-pressure nitrogen source.

8. The experimental apparatus for ground generation and icing of mixed-phase ice crystal particles according to any one of claims 1-7, characterized in that: The water droplet atomization generation system includes a gas-assisted atomizing water nozzle (2), which is connected to a water source and a high-pressure nitrogen source respectively, and sprays out a group of tiny water droplet particles.

9. The experimental apparatus for ground generation and icing of mixed-phase ice crystal particles according to claim 8, characterized in that: The impact surface system includes an impact surface assembly (20) and an impact angle control device (35); the impact surface assembly (20) includes a three-layer structure, namely a top aluminum plate (21), an adjustable constant heat flow heating film (22), and a bottom heat-insulating bakelite (23). The surface temperature of the top aluminum plate (21) can be controlled by adjusting the voltage of the heating film (22).

10. The experimental apparatus for ground generation and icing of mixed-phase ice crystal particles according to claim 9, characterized in that: The measurement system includes a temperature and humidity sensor (24) and a wind speed sensor (25) installed in the air duct (18), as well as a light source (34), a high-speed camera (26) and an infrared camera (27).

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