Optimization method and device for nozzle angle in aerosol pool type washing system, computer program and storage medium

Abstract

The invention discloses a method and a device for optimizing a nozzle angle in an aerosol pool type washing system, a computer program and a storage medium, and relates to the field of research on aerosol behaviors of nuclear facilities, in particular to a method for optimizing sol pool type washing efficiency in a containment discharging and filtering system. The method comprises the following steps: S1, setting a nozzle and a water tank as a gas phase flow domain, and initializing the gas phase flow domain into a water phase; s2, carrying out grid division on the aqueous phase flow domain by adopting an unstructured grid; s3, setting boundary conditions and numerical calculation parameters; s4, simulating gas-liquid-solid three-phase flow; s5, when the jet flow angle is simulated to be 60 degrees, the pool depth is obtained, and it is ensured that jet flow does not impact the bottom of the pool; s6, after the depth of the pool is fixed, simulating washing effects of other jet flow angles; s7, calculating the aerosol washing efficiency under different jet flow angles according to the simulation result; and S8, selecting the jet flow angle with the highest washing efficiency as the angle of the nozzle. The system is suitable for a containment discharging and filtering system of a nuclear power station.

Description

Technical Field

[0001] The invention belongs to the field of nuclear facility aerosol behavior research, and in particular relates to a method for optimizing aerosol pool water washing efficiency in a containment emission filtration system. Background Art

[0002] The containment emission filtration system of a nuclear power plant plays an important role in responding to serious accidents. It is mainly used to control the pressure inside the containment and purify the emission gas to reduce the impact of harmful substances (especially radioactive aerosols and radioactive iodine) on the external environment. Through multi-stage filtration and adsorption devices, the system can effectively remove radioactive substances such as aerosols and radioactive iodine, prevent them from being discharged into the environment, and ensure public safety and ecological safety. At the same time, the system is also equipped with a decompression device and real-time monitoring function to ensure the safety and reliability of the emission process.

[0003] In the existing aerosol pool water washing technology, the aerosol enters the liquid pool through a pipe, and the aerosol particles are captured from the gas phase and retained in the liquid phase through a wet capture mechanism. Factors such as the depth of the liquid pool, the movement of bubbles, and the area of ​​the gas-liquid interface have a significant impact on the water washing effect of the aerosol. The research of the existing technology mainly focuses on the influence of parameters such as the depth of the liquid pool, the diameter of the aerosol particles, the liquid pool temperature, and the spraying pressure on the water washing efficiency. For example, increasing the submergence depth of the water pool can increase the residence time of the aerosol in the liquid phase, thereby enhancing the removal effect; increasing the spraying pressure can enhance the shear effect of the bubbles and improve the capture efficiency of aerosol particles. However, these methods are usually faced with practical space limitations. Increasing the depth of the water pool not only increases the engineering cost, but also leads to structural complexity and uneven liquid flow.

[0004] In the existing technology, the research direction often focuses on the optimization of the above parameters, ignoring the potential impact of nozzle design and jet angle on the water washing effect. In fact, there is a general technical bias in the existing technology, that is, it is believed that increasing the depth of the liquid pool and optimizing the fluid dynamics characteristics in the liquid pool are the main means to improve the water washing efficiency, and it relies too much on the adjustment of these parameters. However, this traditional idea fails to fully consider the role of the nozzle jet angle, resulting in the inability to effectively overcome space limitations and engineering cost issues.

[0005] The present invention is proposed in this context. In view of the limitations of the existing technology that focuses on factors such as liquid pool depth, aerosol diameter, and spray pressure, an innovative research direction starting from the nozzle jet angle is chosen. The present invention overcomes the limitations of traditional methods and proposes a method for optimizing the aerosol water washing efficiency by adjusting the nozzle jet angle rather than increasing the liquid pool depth. By optimizing the nozzle jet angle, the gas-liquid contact area of ​​the bubble and the capture efficiency of the aerosol particles can be significantly improved, thereby improving the water washing efficiency without changing the water pool depth or increasing other difficult-to-overcome parameters. This innovative idea not only breaks through traditional research biases, but also provides a more efficient and economical solution for the purification of nuclear power plant exhaust gases. Summary of the invention

[0006] The present invention optimizes the water washing efficiency by adjusting the jet angle of the nozzle without changing the parameters such as the depth of the liquid pool, the diameter of the aerosol particles, the liquid pool temperature, and the spraying pressure. The specific scheme is as follows:

[0007] A method for optimizing the nozzle angle in an aerosol pool water washing system, the water washing system comprising a pool and a nozzle, the nozzle being located on the inner side wall of the pool, the method comprising:

[0008] S1, setting the nozzle and the water pool as a gas phase flow domain, and initializing it to a water phase step;

[0009] S2, a step of meshing the water phase flow domain using an unstructured grid;

[0010] S3, step of setting boundary conditions and numerical calculation parameters;

[0011] S4, steps for simulating gas-liquid-solid three-phase flow;

[0012] S5, a step of obtaining a depth of the pool when the jet angle is 60° and the jet does not impact the bottom of the pool;

[0013] S6, when the depth of the water pool is fixed, obtaining the remaining jet angles and performing a water washing simulation step;

[0014] S7, a step of obtaining aerosol water washing efficiency by simulating water washing effects of other jet angles;

[0015] S8. Select the jet angle corresponding to the highest aerosol water washing efficiency as the nozzle angle.

[0016] Furthermore, when the unstructured grid is used to divide the water phase flow domain into grids, the grid division adopts an adaptive method, and the grid is encrypted in the nozzle area.

[0017] Furthermore, when setting the boundary conditions, the inlet condition is a mass flow inlet, the outlet condition is an open boundary with zero pressure, and the length of the nozzle is 100 mm, the wall thickness is 1 mm, and the aerosol particles are TiO 2 Solid powder, aerosol density is 4200kg / m3.

[0018] Furthermore, the VOF-coupled level set method is used to track the interface between the gas and liquid phases for water washing of aerosol particles, and is coupled with the DPM model to simulate the gas-liquid-solid three-phase flow in aerosol particle washing.

[0019] Furthermore, when the jet angle is 60°, the pressure cloud map at the bottom of the pool is used to ensure that the jet will not impact the bottom of the pool, and the depth of the pool without scouring is further determined, which is the optimal position of the pool depth when the jet angle is 60°.

[0020] Furthermore, the water washing effect at different jet angles was simulated to obtain the number of aerosol particles escaping at the outlet, thereby obtaining the aerosol water washing efficiency at different jet angles.

[0021] Based on the same inventive concept, the present invention proposes a device for optimizing the nozzle angle in an aerosol pool water washing system, the device comprising:

[0022] Set the nozzle and the pool as a gas phase flow domain and initialize it as a water phase module;

[0023] A module for meshing the water phase flow domain using unstructured grids;

[0024] Module for setting boundary conditions and numerical calculation parameters;

[0025] A module for simulating gas-liquid-solid three-phase flow;

[0026] A module to obtain the depth of the pool when the jet angle is 60° and the jet does not impact the bottom of the pool;

[0027] When the depth of the water pool is fixed, the remaining jet angles are obtained and a module for water washing simulation is performed;

[0028] A module to obtain aerosol water washing efficiency by simulating the water washing effects of other jet angles;

[0029] The module selects the jet angle corresponding to the highest aerosol water washing efficiency as the angle of the nozzle.

[0030] Based on the same inventive concept, the present invention proposes a computer storage medium for storing a computer program. When the computer program is read by a computer, the computer executes the method described in the present invention.

[0031] Based on the same inventive concept, the present invention proposes a computer, including a processor and a storage medium. When the processor reads a computer program stored in the storage medium, the computer executes the method described in the present invention.

[0032] Based on the same inventive concept, the present invention proposes a computer program product, which is a computer program. When the computer program is read, the method described in the present invention is implemented.

[0033] The present invention has the following beneficial effects:

[0034] The present invention reflects the inventor's bold innovation in the traditional research direction, overcoming the prejudice of the existing technology and proposing a new and optimized solution, thereby significantly improving the efficiency of aerosol water washing without increasing the depth of the water pool. Through this innovative research, the inventor not only provides a more cost-effective technical path for the safe emission of gas from nuclear power plants, but also opens up a new research direction in the field of aerosol wet capture technology, which has important innovative and practical value.

[0035] (1) The present invention can find the best water washing effect by optimizing the jet angle of the nozzle, especially under different aerosol mass flow rates. This optimization has significantly improved the removal efficiency of radioactive substances in aerosols, which helps to improve the performance of nuclear facility emission gas purification systems. During the research process, the team found that the interaction between the jet angle and the bubbles played a decisive role in the water washing efficiency. Therefore, by adjusting the jet angle, a more efficient removal effect can be achieved without increasing the depth of the water pool.

[0036] (2) The present invention avoids the engineering costs and technical difficulties caused by increasing the size of the water pool by adjusting the nozzle jet angle instead of increasing the depth of the water pool. In this way, the water washing efficiency can be further improved under the existing water pool conditions, which has high economy and practicality. During the research and development process, the team verified the coordination effect of the water pool depth and the jet angle through repeated experiments, and finally found a solution that can optimize the water washing effect without increasing the size of the water pool.

[0037] (3) When designing the jet angle, the present invention ensures that the jet will not impact the bottom of the pool, effectively avoiding possible scouring of the bottom of the pool. This not only protects the pool structure, but also ensures the stability and continuity of the water washing process. During this process, the invention team repeatedly adjusted the jet angle and analyzed it in combination with the pressure cloud map, and finally determined the optimal position of the pool depth when the jet angle is 60°, thereby avoiding the bottom scouring problem and ensuring the long-term stable operation of the equipment.

[0038] (4) The present invention can accurately evaluate the aerosol water washing efficiency by simulating the water washing effect under different jet angles, thereby providing a scientific basis for optimizing the containment emission filtration system of nuclear power plants. The invention team conducted multiple simulation experiments and repeatedly adjusted the jet angle and other parameters to ensure that the optimization of each design detail can maximize the water washing efficiency. This precise optimization method avoids the experimental blindness in traditional solutions, allowing the optimal solution to be determined during the design phase, improving R&D efficiency and accuracy.

[0039] (5) The method of the present invention is not only applicable to improving the water washing efficiency of the containment emission filtration system of a nuclear power plant, but can also be extended to other similar aerosol capture and purification systems, and has a wide range of applicable value for improving the purification efficiency of the overall system. During the research and development process, the invention team also found that the method can be effectively applied in different system configurations, providing a new technical solution for various aerosol purification systems.

[0040] (6) The present invention is supported by computer simulation and numerical calculation. The present invention can perform optimization analysis without actual experiments, making the design process more efficient and low-cost, and reducing the uncertainty in actual operation. Through this innovation, the invention team has made great efforts in optimizing the calculation model, ensuring the accuracy of the simulation results and avoiding possible errors in actual experiments.

[0041] The present invention is applicable to containment emission filtration systems of nuclear power plants, aerosol removal and purification technology, environmental protection and pollution control, and aerosol emission treatment in industries such as chemical, pharmaceutical and food. By optimizing the pool water washing efficiency, the technology can be widely used in multiphase fluid treatment and waste gas treatment where the aerosol removal efficiency needs to be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 is a flow chart of the optimization method described in Implementation Mode 1;

[0043] Figure 2 This is the calculation area grid structure diagram described in the second implementation mode. The dark long shadow in the figure is the nozzle.

[0044] Figure numerals: a) is a grid structure diagram with a jet angle of 0°; b) is a grid structure diagram with a jet angle of 30°; c) is a grid structure diagram with a jet angle of 45°; d) is a grid structure diagram with a jet angle of 60°;

[0045] Figure 3 This is a top view of the pressure distribution at the bottom of the pool at different jet angles.

[0046] Figure numerals: a) is a pressure distribution diagram of the bottom of the pool with a jet angle of 0°; b) is a pressure distribution diagram of the bottom of the pool with a jet angle of 30°; c) is a pressure distribution diagram of the bottom of the pool with a jet angle of 45°; d) is a pressure distribution diagram of the bottom of the pool with a jet angle of 60°;

[0047] Figure 4 The jet distribution cloud diagrams of 0.1 to 0.8S at different jet angles are shown in FIG. a) for jet distribution cloud diagrams with a jet angle of 0°; b) for jet distribution cloud diagrams with a jet angle of 30°; c) for jet distribution cloud diagrams with a jet angle of 45°; and d) for jet distribution cloud diagrams with a jet angle of 60°.

[0048] Figure 5 It is the water washing efficiency diagram corresponding to the particle size of aerosol particles with different mass fluxes when the jet angle is 0°;

[0049] Figure 6 It is the water washing efficiency diagram corresponding to different jet angles when the mass flux of aerosol particle size is the same;

[0050] Figure 7 It is the change of water washing efficiency at different jet angles. Implementation

[0052] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] Implementation Method 1

[0054] Combined with Figure 1 This embodiment is described. This embodiment provides a method for optimizing the nozzle angle in an aerosol pool water washing system. The water washing system includes a pool and a nozzle. The nozzle is located on the inner side wall of the pool. The method includes:

[0055] S9, setting the nozzle and the water pool as a gas phase flow domain, and initializing it to a water phase step;

[0056] S10, a step of meshing the water phase flow domain using an unstructured grid;

[0057] S11, step of setting boundary conditions and numerical calculation parameters;

[0058] S12, a step of simulating gas-liquid-solid three-phase flow;

[0059] S13, a step of obtaining a depth of the pool when the jet angle is 60° and the jet does not impact the bottom of the pool;

[0060] S14, when the depth of the water pool is fixed, obtaining the remaining jet angles and performing a water washing simulation step;

[0061] S15, a step of obtaining aerosol water washing efficiency by simulating water washing effects of other jet angles;

[0062] S16. Select the jet angle corresponding to the highest aerosol water washing efficiency as the nozzle angle.

[0063] This embodiment provides a method for optimizing the nozzle angle in an aerosol pool water washing system, which can effectively improve the evaluation accuracy of water washing efficiency by accurately simulating the gas-liquid-solid three-phase flow process. By setting the jet angle and pool depth in the aerosol pool, combined with the capture mechanism of different aerosol particles, it is ensured that the water washing effect can be maximized when the pool depth is fixed. This method not only optimizes the aerosol removal process in the pool, but also provides a theoretical basis for aerosol water washing systems in nuclear power plants and other fields, improving their safety and reliability.

[0064] Implementation Method 2

[0065] This embodiment is a further limitation of the first embodiment. Figure 2 To illustrate this embodiment, further, when the water phase flow domain is meshed using an unstructured grid, the meshing is performed using an adaptive method, and mesh encryption is performed in the nozzle area.

[0066] This embodiment improves the accuracy of meshing by using adaptive meshing and mesh encryption in the nozzle area, ensuring detailed simulation of the nozzle area. This helps to more accurately capture the changes in the flow field around the nozzle, thereby improving the reliability and accuracy of the water washing simulation results.

[0067] Implementation Method 3

[0068] This embodiment is a further limitation of the first embodiment. Further, when setting the boundary conditions, the inlet condition is a mass flow inlet, the outlet condition is an open boundary with zero pressure, and the length of the nozzle is 100 mm, the wall thickness is 1 mm, and the aerosol particles are TiO 2 Solid powder, aerosol density is 4200kg / m3.

[0069] This embodiment further improves the accuracy of the simulation by setting more precise boundary conditions and specifying specific parameters of the nozzle. The physical reality of the model is enhanced through precise aerosol particle settings, which helps to better simulate the aerosol water washing process in actual operation.

[0070] Implementation Method 4

[0071] This embodiment is a further limitation of the first embodiment. Furthermore, the VOF-coupled level set method is used to track the interface between the gas phase and the liquid phase for water washing of aerosol particles, and is coupled with the DPM model to simulate the gas-liquid-solid three-phase flow in the water washing of aerosol particles.

[0072] This implementation effectively simulates the gas-liquid-solid three-phase flow by using the VOF coupled level set method and the DPM model. This method can accurately track the changes in the gas-liquid interface and ensure the dynamic capture of aerosol particles during the water washing process, thereby improving the water washing efficiency and ensuring the accurate analysis of the aerosol particle removal effect.

[0073] Implementation Method 5

[0074] This embodiment is a further limitation of the first embodiment. Figure 3 To illustrate this embodiment, further, when the jet angle is 60°, the pressure cloud diagram at the bottom of the pool is used to ensure that the jet does not impact the bottom of the pool, and the depth of the pool without scouring is further determined, and the depth is the optimal position of the pool depth when the jet angle is 60°.

[0075] This embodiment analyzes the pressure cloud map at the bottom of the pool to ensure that the jet does not impact the bottom of the pool when the jet angle is 60°, and then determines the optimal pool depth without scouring. This depth corresponds to the position where the jet effect is best, effectively avoiding potential impact on the bottom of the pool and ensuring the stability and efficiency of the water washing process.

[0076] Implementation Method 6

[0077] This embodiment is a further limitation of the first embodiment. Figure 4-7 To illustrate the present embodiment, the water washing effect at different jet angles is further simulated to obtain the number of aerosol particles escaping at the outlet, thereby obtaining the aerosol water washing efficiency at different jet angles.

[0078] This embodiment simulates the water washing effect under different jet angles and accurately calculates the number of aerosol particles escaping at the outlet, thereby obtaining the aerosol water washing efficiency under different jet angles. Through this simulation analysis, the influence of different jet angles on the water washing effect can be clarified, thereby providing a theoretical basis for the optimization of aerosol water washing equipment. In practical applications, the optimal jet angle can be selected according to the characteristics and emission of the aerosol to ensure maximum removal efficiency. In addition, this method helps to improve the energy saving and economy of the equipment, optimize the design and operating conditions, and improve the overall performance of the water washing system.

[0079] Implementation Method 7

[0080] This embodiment provides an example, which is used to explain the above-mentioned embodiments 1 to 6. The specific example is as follows:

[0081] Due to the complex removal mechanism during the water washing process, it is difficult to achieve real-time video observation of the water washing process, and it is impossible to grasp parameters such as the shape and pressure of the water jet. However, by simulating the jet flow field through the CFD (Computational Fluid Dynamic) method, the jet flow structure and the factors affecting the water washing efficiency can be accurately and specifically obtained.

[0082] Combination Figure 1-6 This embodiment describes a method for safely improving the efficiency of pool-type immersion jet washing in a filtration system, including the following steps:

[0083] Step 1: Set the nozzle and the pool as a flow domain of the gas phase and initialize it to the water phase;

[0084] Step 2: Use unstructured grid to divide the flow domain and encrypt the grid at the nozzle;

[0085] Step 3, given boundary conditions and numerical calculation parameters, where the inlet condition is given as a mass flow inlet, and the outlet condition is given as an open boundary with zero pressure;

[0086] Step 4: Use the VOF coupled level set method to track the gas-liquid interface, and couple it with the DPM model (DiscretePhase Model is a model used to simulate the motion trajectory of a small number of discrete particles in the flow field and their interaction with the continuous phase (such as gas or liquid)) to study the gas-liquid-solid three-phase flow in the air immersion water washing process. When the turbulence model is selected, the SSTk-w model solves the gas-liquid two-phase flow of the jet flow field;

[0087] Step 5: Select a certain working condition with a maximum jet angle of 60° to analyze the jet flow structure. The conditions of the certain working condition are: the nozzle length is 100 mm and the wall thickness is 1 mm. The aerosol particles are TiO 2 Solid powder, aerosol density is 4200kg / m3. According to the above working conditions, the depth of the pool where the jet does not scour the bottom of the pool is obtained;

[0088] Step 7: Find the lowest nozzle position corresponding to the remaining jet angles under this working condition, and then perform water washing simulation analysis

[0089] Step 8: Obtain the water washing efficiency corresponding to different jet angles under the working condition and the incident angle with the highest water washing efficiency.

[0090] The present invention uses an air mass flux of 440kg / m2 The washing process of s is analyzed as an example to obtain the following results, and the specific implementation process is as follows:

[0091] Flow field simulation solution

[0092] The computational domain of the submerged jet flow is as follows: Figure 2 As shown in the figure, the overall unstructured grid is used, and the grid quality is above 0.76. Because it plays a key role in the subsequent high-speed jet flow, the grid of the nozzle part needs to be encrypted. Finally, the number of grids in this area is determined to be 3.28 million. The grids of each working condition are as follows: Figure 2 As shown in a)b)c)d).

[0093] The phase flow model selects the two-phase VOF model and chooses to use explicit volume fraction parameters. While using the VOF method, the Level Set method is inserted to track the gas-liquid two-phase interface, and the SSTk-w model is selected for calculation, which can better describe the motion morphology of the jet. The present invention selects the PISO algorithm (Pressure-Implicit with Splitting of Operators) to solve the pressure and velocity in the flow field. The volume fraction selects the Geo-Reconstruct method for discretization, the pressure selects the PRESTO! method, the gradient selects the Least Squares Cell Based method, and the rest selects the Second Order Upwind method. Choose to keep the default sub-relaxation factor, and the Courant number is 2.5.

[0094] The working media in the jet flow field are air and water at 20°C, the reference pressure is 1 standard atmosphere, the given inlet condition is mass flow rate, and the nozzle outlet mass flux is 440kg / m 2 s. The outlet is set as an open boundary with zero pressure. This setting does not require setting the flow direction on the boundary and has good stability and convergence. The jet angle of 0° to 60° (the angle between the jet exit direction and the centerline direction of the tube is defined as the jet angle) is selected for jet flow field analysis.

[0095] Immersion jet washing analysis

[0096] During the water washing process, the particle removal efficiency is mainly affected by the jet flow state. Therefore, four angles, 0°, 30°, 45° and 60°, are taken to describe the flow field characteristics when the jet angle changes.

[0097] like Figure 3 As shown in the figure, according to the stress conditions at the bottom of the pool under different nozzle jet angles, the pool depth under the mass flux is obtained by extracting the bottom pressure conditions when the jet angle is 60°. It is observed that the bottom pressure of the pool under all working conditions is within a reasonable range.

[0098] like Figure 4 As shown in the figure, according to the jet distribution cloud diagram at different jet angles, as the gas in the nozzle continues to enter, the jet continues to develop in the water and the volume increases. The momentum in the x direction of the front end of the jet gradually decreases, and the buoyancy effect is obvious at this time. The gas in the front end of the jet continues to gather to form a sac-like structure that continues to float up under the action of buoyancy. As the sac-like structure continues to rise, it gradually moves away from the momentum jet at the nozzle outlet in the y direction. Finally, the two separate and the sac-like structure moves independently. As the jet angle gradually increases, the penetration length of the jet decreases, and part of the gas flows back along the nozzle.

[0099] like Figure 5 As shown in the figure, according to the water washing efficiency diagram of different mass fluxes when the jet angle is 0°, it can be seen that in all different mass flux conditions, the water washing efficiency first decreases and then increases with the increase of particle size, and the aerosol decontamination factor first decreases and then increases with the increase of particle size. The aerosol particle size corresponding to the lowest point of the decontamination factor is between 0.5 and 0.8 m.

[0100] Depend on Figure 5 It can be seen that with the increase of particle size, for each carrier gas flow condition, the removal efficiency of aerosol particles does not increase monotonically linearly, but will pass through three different areas. For aerosol particles with a diameter less than 0.3, with the increase of particle size, the aerosol water washing efficiency changes very little, almost tending to a straight line, which shows that for aerosol particles in this area, the water washing purification efficiency is almost unaffected by the increase of carrier gas flow rate; and as the particle size gradually increases, for aerosol particles in the range of 0.3m-0.5m, when the particle size increases, the aerosol water washing purification efficiency decreases instead: and for aerosol particles with a particle size greater than 0.5m, with the increase of aerosol particle size, the aerosol water washing efficiency increases rapidly.

[0101] according to Figure 5From the changing trend of , we can know that the particle size has a very dramatic effect on the removal of aerosols. Aerosols of different particle sizes are affected by different factors. For small-particle aerosols, the aerosols are mainly affected by Brownian diffusion and other factors, which cause the aerosols to settle in the water. For aerosol particles with a particle size of less than about 0.3 microns, as the particle size increases, the effect of Brownian diffusion gradually weakens, which will lead to a decrease in the water washing efficiency of the aerosols: On the other hand, as the particle size increases, inertial collision and gravity cause the aerosols to settle more easily, which will lead to an increase in the water washing efficiency of the aerosols. Under the coupling of different mechanisms, it was observed that the water washing efficiency of aerosol particles in this area basically does not change with the increase of particle size. For aerosol particles with a particle size of 0.3-0.5 microns, the results show that the aerosol water washing efficiency gradually decreases with the increase of particle size. This may be because for aerosol particles in this particle size range, the decrease in aerosol water washing efficiency caused by Brownian dispersion is more dominant than the increase in aerosol water washing efficiency caused by gravity and inertial collision. Therefore, as the particle size increases, the aerosol water washing efficiency gradually decreases within this range. For large aerosol particles with a particle size greater than 0.5 microns, it is easy to observe in the figure that as the particle size increases, the water washing efficiency of aerosol particles in this range will gradually increase. This shows that within this range, the aerosol moves into the water mainly due to inertial collision and gravity. As the particle size increases, the effects of inertial collision and gravity are enhanced, and the aerosol is more likely to settle in the water.

[0102] Effect of different jet angles on water washing efficiency

[0103] like Figure 6 As shown in the figure, according to the water washing efficiency diagram of different jet angles at the same mass flux, the aerosol removal efficiency increases with the increase of the jet angle. The water washing efficiency of aerosols in the 0.3-0.5 micron range does not change much, and the water washing effect becomes more obvious as the particle size increases. The reason is that aerosols with large particles larger than 0.5 microns are mainly removed due to inertial collision and gravity, while the gas with the jet angle has a more intense effect on the water in the water tank, thereby improving the water washing efficiency.

[0104] Figure 7 The figure shows the change of water washing efficiency at different jet angles. The aerosol removal efficiency increases with the increase of the jet angle, which indicates that the water washing efficiency can be improved without changing the depth of the water pool by the method of the present invention.

[0105] The technical solution provided by the present invention is further described in detail through the above specific implementation modes in order to highlight the advantages and benefits of the technical solution provided by the present invention. However, the above specific implementation modes are not intended to limit the present invention. Any reasonable modification and improvement of the present invention, combination of implementation modes and equivalent substitution within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

[0106] Those skilled in the art will appreciate that the above are only preferred embodiments of the present invention, and the various embodiments of the present disclosure and / or the features described in the claims may be combined or combined in various ways, even if such combinations or combinations are not explicitly described in the present disclosure. It is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments, or perform equivalent substitutions on some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

[0107] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for optimizing the nozzle angle in an aerosol pool water washing system, the water washing system comprising a pool and a nozzle, the nozzle being located on the inner side wall of the pool, characterized in that: The method comprises: S1, setting the nozzle and the water pool as a gas phase flow domain, and initializing it to a water phase step; S2, a step of meshing the water phase flow domain using an unstructured grid; S3, step of setting boundary conditions and numerical calculation parameters; S4, steps for simulating gas-liquid-solid three-phase flow; S5, a step of obtaining the depth of the pool when the jet angle is 60° and the jet does not impact the bottom of the pool; S6, when the depth of the water pool is fixed, obtaining the remaining jet angles and performing a water washing simulation step; S7, a step of obtaining aerosol water washing efficiency by simulating water washing effects at different jet angles; S8, a step of selecting a jet angle corresponding to the highest aerosol water washing efficiency as the angle of the nozzle.

2. The detection method according to claim 1, characterized in that: In S2, when the water phase flow domain is meshed using an unstructured grid, the meshing is done using an adaptive method, and mesh encryption is performed in the nozzle area.

3. The detection method according to claim 1, characterized in that: In S3, when setting the boundary conditions, the inlet condition is a mass flow inlet, the outlet condition is an open boundary with zero pressure, the length of the nozzle is 100 mm, the wall thickness is 1 mm, the aerosol particles are TiO2 solid powder, and the aerosol density is 4200 kg / m 3 .

4. The detection method according to claim 1, characterized in that: In S4, the VOF-coupled level set method is used to track the interface between the gas phase and the liquid phase for water washing of aerosol particles, and is coupled with the DPM model to simulate the gas-liquid-solid three-phase flow in the water washing of aerosol particles.

5. The detection method according to claim 1, characterized in that: In S5, when the jet angle is 60°, the pressure cloud map at the bottom of the pool is used to ensure that the jet does not impact the bottom of the pool, and the depth of the pool without scouring is further determined, and the depth is the optimal position of the pool depth when the jet angle is 60°.

6. The detection method according to claim 1, characterized in that: In S7, the method for simulating the water washing effect under different jet angles is to obtain the number of aerosol particles escaping from the outlet after determining the jet angle, thereby obtaining the aerosol water washing efficiency corresponding to the jet angle.

7. An optimization device for nozzle angle in an aerosol pool water washing system, characterized in that: The device comprises: Set the nozzle and the pool as a gas phase flow domain and initialize it as a water phase module; A module for meshing the water phase flow domain using unstructured grids; Module for setting boundary conditions and numerical calculation parameters; A module for simulating gas-liquid-solid three-phase flow; A module to obtain the depth of the pool when the jet angle is 60° and the jet does not impact the bottom of the pool; When the depth of the water pool is fixed, the remaining jet angles are obtained and a module for water washing simulation is performed; A module to obtain aerosol water washing efficiency by simulating the water washing effects of other jet angles; The module selects the jet angle corresponding to the highest aerosol water washing efficiency as the angle of the nozzle.

8. A computer storage medium for storing a computer program, characterized in that: When the computer program is read by a computer, the computer executes the method according to any one of claims 1 to 6.

9. A computer, comprising a processor and a storage medium, characterized in that: When the processor reads the computer program stored in the storage medium, the computer executes the method according to any one of claims 1 to 6.

10. A computer program product, being a computer program, characterized in that When the computer program is read, the method according to any one of claims 1 to 6 is implemented.

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