A numerical simulation method for double-stranded jet impingement atomization and related device

Abstract

The application discloses a double-jet impinging atomization numerical simulation method and a related device, and belongs to the technical field of cold-state atomization; a calculation domain is established, and a three-dimensional pipeline model is established according to pipeline parameters; then, explicit calculation and implicit calculation are performed on the three-dimensional pipeline model; finally, particle information in the calculation process is exported and post-processing analysis is performed. The application can analyze and three-dimensionally visually display the liquid breaking process, breaking mechanism, particle distribution state, atomization angle and average droplet size in the atomization field of double-jet impinging atomization, and the accuracy of the result is determined through three-dimensional numerical simulation research, thereby providing an intuitive theoretical basis for the prediction of the atomization field of double-jet impinging atomization and the in-depth analysis of atomization results.

Description

Technical Field

[0001] This invention belongs to the field of cold atomization technology and relates to a numerical simulation method and related apparatus for dual-jet impact atomization. Background Technology

[0002] Dual-jet impingement atomizing nozzles are widely used in liquid rocket engines due to their simple structure and excellent atomization characteristics. The mixing and atomization characteristics of oxidizer and propellant have a significant impact on combustion stability and thrust characteristics within the engine. The quality of atomization directly affects ignition, combustion efficiency, and flame stability. Therefore, research on the atomization mechanism of dual-jet impingement atomization is of great significance for engine design.

[0003] Existing research methods can be broadly categorized into three types: experimental simulation, meshed numerical simulation, and meshless numerical simulation. However, experimental methods suffer from poor accuracy in analyzing atomization field characteristics, and meshed methods are prone to convergence issues when dealing with large deformation problems such as impact atomization. Meshless methods, on the other hand, offer high accuracy in post-processing and do not exhibit convergence issues due to mesh limitations when calculating large deformation problems. In the numerical simulation of dual-jet impact atomization using the semi-implicit moving particle method, the physical quantities of each fluid particle are obtained by weighted averaging the physical quantities of other fluid particles within a spherical region centered on that particle and with a radius equal to 1.2 times the interparticle spacing. There are no fixed topological relationships between particles, which is a fundamental condition for this method to easily simulate large deformation flows.

[0004] However, current experimental and numerical simulation methods struggle to accurately obtain the distribution characteristics and droplet size variation patterns of droplets within the fog field during post-processing, hindering engine design. Summary of the Invention

[0005] The purpose of this invention is to solve the technical problem that it is difficult to accurately obtain the distribution characteristics and droplet size variation law of droplets in the fog field in the prior art, and to provide a numerical simulation method and related device for dual-jet impact atomization.

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

[0007] In a first aspect, the present invention provides a numerical simulation method for dual-jet impact atomization, comprising the following steps:

[0008] Establish the computational domain and build a three-dimensional pipeline model based on the pipeline parameters;

[0009] Perform explicit and implicit calculations on the 3D pipeline model;

[0010] The particle information from the calculation process is exported and then post-processed for analysis.

[0011] Secondly, the present invention provides a numerical simulation system for dual-jet impact atomization, comprising:

[0012] The modeling module is used to establish the computational domain and create a 3D pipeline model based on the pipeline parameters.

[0013] The calculation module is used to perform explicit and implicit calculations on the 3D pipeline model;

[0014] The analysis module is used to export particle information from the calculation process and perform post-processing analysis.

[0015] Thirdly, the present invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the numerical simulation method for dual-jet impact atomization as described above.

[0016] Fourthly, the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the numerical simulation method for dual-jet impact atomization as described above.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] This invention discloses a numerical simulation method and related apparatus for dual-jet impact atomization. Using a meshless numerical simulation method, it realizes the entire process in three-dimensional space from the formation of a liquid film after jet atomization, the breakup of the liquid film into liquid filaments, and the further formation of liquid droplets. The established numerical model can calculate dual-jet impact atomization with different mass flow rates and impact angles, and analyzes and visualizes the liquid breakup process, breakup mechanism, particle distribution, atomization angle, and average droplet size within the atomization field. This invention, through three-dimensional numerical simulation, confirms the accuracy of the results, achieving accurate prediction and post-processing analysis of the liquid breakup atomization process based on a dual-jet impact atomization nozzle. It provides an intuitive theoretical basis for fog field prediction and in-depth analysis of atomization results in dual-jet impact atomization. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a flowchart of the method of the present invention;

[0021] Figure 2 This is a schematic diagram of the system of the present invention;

[0022] Figure 3 This is a comparison chart of numerical simulation results and experimental results under the same working conditions, calculated by the present invention under the conditions of an impact angle of 60° and a mass flow rate of 10g / s.

[0023] Figure 4 The steady-state fog field diagram calculated for this invention is shown under the conditions of an impact angle of 60° and a mass flow rate of 25 g / s.

[0024] Figure 5 This is a diagram showing the distribution of droplets of different volumes in a steady-state fog field under the conditions of an impact angle of 60° and a mass flow rate of 25 g / s, as calculated in this invention.

[0025] Figure 6 This is the post-processing result of the present invention under the condition of different jet velocities at the same impact angle;

[0026] Figure 7 This is a steady-state fog field diagram calculated for an impact angle of 45° and a mass flow rate of 10 g / s, as per the present invention.

[0027] Figure 8 This diagram shows the distribution of droplets of different volumes in a steady-state fog field under the conditions of an impact angle of 45° and a mass flow rate of 10 g / s, as calculated in this invention.

[0028] Figure 9 This is the post-processing result of the present invention under the condition of different impact angles at the same jet velocity;

[0029] Figure 10 This invention provides post-processing calculations for the droplet size across the entire fog field under all stable operating conditions.

[0030] Figure 11 This is a schematic diagram illustrating the principle of droplet particle staining based on a recursive method in this invention.

[0031] Figure 12 This is a schematic diagram of the computer device structure of the present invention. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0033] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0034] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0035] In the description of the embodiments of the present invention, it should be noted that if terms such as "upper," "lower," "horizontal," or "inner" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, terms such as "first" and "second" are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0036] Furthermore, the use of the term "horizontal" does not imply that the component must be absolutely horizontal, but rather that it can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal than "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0037] In the description of the embodiments of the present invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention according to the specific circumstances.

[0038] The present invention will now be described in further detail with reference to the accompanying drawings:

[0039] See Figure 1 This invention provides a numerical simulation method for dual-jet impact atomization, comprising the following steps:

[0040] S1. Establish the computational domain and build a three-dimensional pipeline model based on the pipeline parameters;

[0041] S2 performs explicit and implicit calculations on the three-dimensional pipeline model;

[0042] S3 exports the particle information from the calculation process and performs post-processing analysis.

[0043] In one feasible embodiment of the present invention, the computational domain includes a liquid film region, a liquid filament region, and a fully developed region when the fog field is stable.

[0044] In one feasible embodiment of the present invention, the step of establishing a three-dimensional pipeline model based on pipeline parameters includes: determining the pipeline inner diameter r1, pipeline outer diameter r2, pipeline length L, pipeline axis normal vector a, pipeline axis starting point coordinate b, and particle spacing r, and setting the inlet boundary velocity condition, inlet boundary position, and outlet boundary position based on actual needs.

[0045] In one feasible embodiment of the present invention, the explicit and implicit calculations in the three-dimensional pipeline model include:

[0046] S201, set the import boundary conditions and export boundary conditions, set parameters and initialize variables;

[0047] S202, solve the viscous and volume force terms in the basic governing equations of fluid mechanics, and perform explicit calculations;

[0048] S203, construct a matrix to solve the pressure Poisson equation;

[0049] S204 calculates the pressure gradient and implicitly corrects the particle position information.

[0050] In one feasible embodiment of the present invention, the step of exporting particle information from the calculation process and performing post-processing analysis includes:

[0051] S301, export the particle information from the calculation processes of S202, S203 and S204;

[0052] S302 uses the exported particle information to perform post-processing analysis on the calculation results, determines the stabilization time and stabilization state of the fog field, and analyzes the atomization angle, average droplet size, and spatial distribution and trend of droplet size in the atomization field of the dual-jet impact atomization.

[0053] In one feasible embodiment of the present invention, S302 specifically includes:

[0054] (1) The droplets in the fog field are distinguished by recursion and the state information of each droplet is obtained;

[0055] (2) Based on the state information of each droplet, analyze the volume, position and atomization angle of each droplet;

[0056] (3) Based on the volume, position and atomization angle of the droplets, the fog field characteristics at stable times under multiple working conditions are statistically analyzed to obtain the variation law of particle size and fog field characteristics under each working condition.

[0057] The principle behind the recursive idea is as follows:

[0058] Figure 11 (a) represents the relative positions of the particles, where the radius of action of the kernel function is r. e Let be the search radius. Taking particle a in Figure (a) as an example, and particles b and c within the search range, then a, b, and c are considered to be particles within the same droplet. Figure 11 (b) is a schematic diagram of the staining process. First, a recursive search is performed on particle a to find neighboring particles b and c, and these are then stained. Next, a recursive search is performed on neighboring particles d and e of particle b, and these are stained as well. Once the recursive search for particle b is complete, the same recursive search is performed on particle c until the search ends, thus completing the staining process for particle a. Other particles are stained in the same way. Finally, particles with the same color are determined to be within the same droplet; thus, the states of all droplets in the fog field are obtained.

[0059] See Figure 2 This invention provides a numerical simulation system for dual-jet impact atomization, comprising:

[0060] The modeling module is used to establish the computational domain and create a 3D pipeline model based on the pipeline parameters.

[0061] The calculation module is used to perform explicit and implicit calculations on the 3D pipeline model;

[0062] The analysis module is used to export particle information from the calculation process and perform post-processing analysis.

[0063] See Figure 12 This invention provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. The device is characterized in that the processor executes the computer program to implement the steps of the numerical simulation method for dual-jet impact atomization.

[0064] This invention provides a computer-readable storage medium storing a computer program, characterized in that the computer program, when executed by a processor, implements the steps of the numerical simulation method for dual-jet impact atomization.

[0065] Example:

[0066] Establish the computational domain; the computational domain for dual-jet impact atomization should be able to include the liquid film region, liquid filament region, and fully developed region when the fog field is stable. The physical parameters of the medium water in this numerical simulation are shown in the table below:

[0067] Table 1

[0068]

[0069] The coordinates of the computational domain in this embodiment are shown in the table below:

[0070] Table 2

[0071]

[0072] The computational domain cannot be too large, otherwise the computational efficiency will be greatly reduced; nor can it be too small, otherwise the particles will be deleted because they exceed the computational domain.

[0073] 3D pipeline modeling.

[0074] 3D pipeline modeling requires determining six specific parameters: pipeline inner diameter r1, pipeline outer diameter r2, pipeline length L, pipeline axis normal vector a, pipeline axis starting point coordinates b, and particle spacing r. The pipeline modeling data in this embodiment is as follows:

[0075] Table 3

[0076]

[0077] Set inlet and outlet boundary conditions, set parameters, and initialize variables;

[0078] The import boundary conditions are set at the fully developed speed of imports, with a maximum speed of u. max The velocity formula is R is the inner diameter of the pipe, and d is the distance between the fluid particles in the inlet region and the pipe axis.

[0079] Solve the viscous and volume force terms in the fundamental governing equations of fluid mechanics by performing explicit calculations;

[0080] Construct a matrix to solve the pressure Poisson equation;

[0081] Solve for the pressure gradient and perform implicit calculations to correct information such as particle position.

[0082] Export particle information during the calculation process;

[0083] The calculation results are post-processed and analyzed to determine the stabilization time and stabilization state of the fog field. The atomization cone angle, average droplet size, and spatial distribution and variation trend of the droplet size of the atomization field of the dual jet impact atomization are analyzed.

[0084] When calculating the average droplet diameter within the atomization field, the entire atomization field is divided into segments every 5 mm along the direction of atomization development, starting from the pipe inlet. The Sottle average diameter within each segment is calculated using equation (1):

[0085]

[0086] When analyzing the distribution of droplet size, it is necessary to first divide the droplets in the entire fog field into several parts according to their volume, and then obtain the positional distribution of droplets within different volume ranges.

[0087] Based on the droplet size distribution and droplet volume distribution under different operating conditions, the distribution characteristics of droplets in the dual-jet impact atomization field can be obtained.

[0088] The numerical simulation results under the conditions of an impact angle of 60° and a mass flow rate of 10 g / s are shown in [reference]. Figure 3 (b) and Figure 3 (d); See the experimental results under the same working conditions. Figure 3 (a) and Figure 3 (c);

[0089] The steady-state fog field diagram under the conditions of an impact angle of 60° and a mass flow rate of 25 g / s is shown in the figure. Figure 4 ;

[0090] When the impact angle is 60° and the mass flow rate is 25 g / s, the steady-state droplet distribution diagram of different volumes in the fog field is shown below. Figure 5 ;in Figure 5 (a) represents a volume of 0.000524 mm. 3 ~0.031mm 3 A diagram showing the distribution of droplets. Figure 5 (b) is a volume of 0.032 mm. 3 ~0.058mm 3 A diagram showing the distribution of droplets. Figure 5 (c) represents a volume of 0.064 mm. 3 ~0.067mm 3 A diagram showing the distribution of droplets. Figure 5 (d) represents a volume of 0.11 mm. 3 A diagram showing the distribution of droplets. Figure 5 (e) represents a volume of 6.26 mm. 3 The droplet distribution diagram is shown below. Numerical simulation results and experimental quantitative results are shown in the table below:

[0091] Table 4

[0092]

[0093] For post-processing results under the same impact angle but different jet velocities, please refer to [link / reference]. Figure 6 ;

[0094] The steady-state fog field diagram under the conditions of an impact angle of 45° and a mass flow rate of 10 g / s is shown below. Figure 7 ;

[0095] The distribution of droplets of different volumes in the steady-state fog field under the condition of an impact angle of 45° and a mass flow rate of 10 g / s is shown in the figure. Figure 8 ;in Figure 8 (a) represents a volume of 0.000524 mm. 3 -0.195mm 3 A diagram showing the distribution of droplets. Figure 8 (b) is a volume of 0.238 mm. 3 -0.325mm 3 A diagram showing the distribution of droplets. Figure 8 (c) represents a volume of 0.460 mm. 3 -0.551mm 3 A diagram showing the distribution of droplets. Figure 8 (d) represents a volume of 1.382 mm. 3 A diagram showing the distribution of droplets. Figure 8 (e) represents a volume of 10.866 mm. 3 The droplet distribution location diagram.

[0096] For post-processing results under the same jet velocity but different impact angles, see [link / reference]. Figure 9 ;

[0097] Figure 10 This invention provides post-processing calculations for the droplet size across the entire fog field under all stable operating conditions.

[0098] This invention utilizes a meshless numerical simulation method to realize the entire process of liquid film formation, liquid film breakup into liquid filaments, and further liquid filament formation into droplets in three-dimensional space after jet atomization. The established numerical model can calculate the impact atomization of dual jets with different mass flow rates and impact angles, and analyzes and visualizes the liquid breakup process, breakup mechanism, particle distribution, atomization angle, and average droplet size within the atomization field. The established numerical model provides a theoretical basis for accurate prediction and intuitive analysis of the breakup process and results of flows under different inlet and outlet boundary conditions.

[0099] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0100] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0101] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0102] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A numerical simulation method for dual-jet impact atomization, characterized in that, Includes the following steps: Establish the computational domain and build a three-dimensional pipeline model based on the pipeline parameters; Explicit and implicit calculations are performed on the 3D pipeline model; specifically including: S201, set the import boundary conditions and export boundary conditions, set parameters and initialize variables; S202, solve the viscous and volume force terms in the basic governing equations of fluid mechanics, and perform explicit calculations; S203, construct a matrix to solve the pressure Poisson equation; S204, solve for the pressure gradient and perform implicit calculations to correct the particle position information; The particle information from the calculation process is exported and post-processed for analysis; specifically including: S301, export the particle information from the calculation processes of S202, S203 and S204; S302, using the exported particle information, performs post-processing analysis on the calculation results to determine the stabilization time and stable state of the fog field, and analyzes the atomization angle, average droplet size, and spatial distribution and trend of the droplet size in the atomization field of the dual-jet impact atomization; specifically including: (1) The droplets in the fog field are distinguished by recursion and the state information of each droplet is obtained; (2) Based on the state information of each droplet, analyze the volume, position and atomization angle of each droplet; (3) Based on the volume, position and atomization angle of the droplets, the fog field characteristics at stable times of multiple working conditions are statistically analyzed to obtain the variation law of particle size and fog field characteristics under each working condition.

2. The numerical simulation method for dual-jet impact atomization according to claim 1, characterized in that, The computational domain includes the liquid film region, the liquid filament region, and the fully developed region when the fog field is stable.

3. The numerical simulation method for dual-jet impact atomization according to claim 2, characterized in that, The process of establishing a three-dimensional pipeline model based on pipeline parameters includes: determining the pipeline inner diameter r1, pipeline outer diameter r2, pipeline length L, pipeline axis normal vector a, pipeline axis starting point coordinate b, and particle spacing r; and setting the inlet boundary velocity conditions, inlet boundary position, and outlet boundary position based on actual needs.

4. A numerical simulation system for dual-jet impact atomization, characterized in that, include: The modeling module is used to establish the computational domain and create a 3D pipeline model based on the pipeline parameters. The calculation module is used to perform explicit and implicit calculations on the 3D pipeline model; specifically, it includes: S201, set the import boundary conditions and export boundary conditions, set parameters and initialize variables; S202, solve the viscous and volume force terms in the basic governing equations of fluid mechanics, and perform explicit calculations; S203, construct a matrix to solve the pressure Poisson equation; S204, solve for the pressure gradient and perform implicit calculations to correct the particle position information; The analysis module is used to export particle information from the calculation process and perform post-processing analysis; specifically, it includes: S301, export the particle information from the calculation processes of S202, S203 and S204; S302, using the exported particle information, performs post-processing analysis on the calculation results to determine the stabilization time and stable state of the fog field, and analyzes the atomization angle, average droplet size, and spatial distribution and trend of the droplet size in the atomization field of the dual-jet impact atomization; specifically including: (1) The droplets in the fog field are distinguished by recursion and the state information of each droplet is obtained; (2) Based on the state information of each droplet, analyze the volume, position and atomization angle of each droplet; (3) Based on the volume, position and atomization angle of the droplets, the fog field characteristics at stable times of multiple working conditions are statistically analyzed to obtain the variation law of particle size and fog field characteristics under each working condition.

5. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method as described in any one of claims 1-3.

6. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1-3.

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