Method and System for Evaluating the Machining Performance of Structured Grinding Wheels for Grinding Optical Components

Abstract

This invention provides a method and system for evaluating the machining performance of structured grinding wheels used in the grinding of optical components. The method includes: constructing a structured grinding wheel model with multiple groove configurations and an overall geometric model of the grinding system based on the target machining object and machining environment of fused silica optical components; then converting these models into a three-dimensional airflow field simulation model to screen candidate grinding wheel configurations with the highest air barrier weakening strength among the various groove configurations; updating the grinding wheel configurations in the overall geometric model to the candidate configurations; adding a grinding fluid nozzle model to the replaced overall geometric model of the grinding system and converting it into a gas-liquid two-phase flow simulation model; in the gas-liquid two-phase flow simulation model, setting multiple groove size parameters based on the candidate grinding wheel configurations and using a preset grinding fluid injection speed for simulation calculation; selecting the target groove parameter with the largest effective flow rate; and finally, verifying the performance of the grinding wheel with the target groove parameter. This method improves the accuracy of machining performance simulation evaluation.

Description

Technical Field

[0001] This invention relates to the field of data processing technology, and more specifically to a method and system for evaluating the machining performance of structured grinding wheels used for grinding optical components. Background Technology

[0002] Optical components are the core foundational parts of precision optical equipment, widely used in major scientific and technological projects such as aerospace, defense, high-power laser systems, and space observation. Their manufacturing precision and surface quality directly determine the performance of high-end optical equipment. Fused silica, as a typical hard, brittle, and difficult-to-machine material, is the core substrate for high-end optical components. Grinding is a key process in the precision and ultra-precision manufacturing of fused silica optical components, directly determining the surface accuracy, surface quality, and processing efficiency of subsequent polishing processes.

[0003] During high-speed rotary grinding, traditional grooveless grinding wheels form a stable air barrier layer on their surface, severely hindering the entry of grinding fluid into the grinding zone. This results in insufficient cooling and lubrication, leading to defects such as high grinding force, high grinding temperature, and surface scratches and chipping on the workpiece. This fails to meet the low-damage, high-precision machining requirements of fused silica optical components. Surface-structured grinding wheels, by machining grooves of specific geometries on their surface, can effectively disturb the airflow field, weaken the air barrier layer, and provide circulation channels for the grinding fluid. Simultaneously, they improve chip removal capacity and reduce grinding force and heat, representing a core technological approach to solving the defects in fused silica grinding.

[0004] Current research on structured grinding wheels relies heavily on empirical parameter optimization for groove parametric design. There is a lack of systematic and complete quantitative simulation and evaluation methods for machining performance. This makes it impossible to accurately reveal the influence of groove structure on the weakening of the air barrier layer in the grinding zone and the characteristics of grinding fluid supply. It also makes it impossible to achieve gradient optimization design of grinding wheel structure, which restricts the engineering application of structured grinding wheels in the field of precision grinding of fused silica optical components. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for evaluating the machining performance of structured grinding wheels used in the grinding of optical components. The specific technical solution adopted is as follows: In a first aspect, embodiments of the present invention provide a method for evaluating the machining performance of a structured grinding wheel used for grinding optical components, the method comprising: Based on the target processing object and processing environment of fused silica optical element grinding, a structured grinding wheel model with multiple groove configurations and an overall geometric model of the grinding system are constructed. The overall geometric model of the grinding system is meshed and its physical parameters are set to convert the overall geometric model of the grinding system into a three-dimensional airflow field simulation model that can be used for mathematical calculations. Based on the three-dimensional airflow field simulation model, the air barrier weakening strength of each group of groove configurations is calculated, and the groove configuration with the highest air barrier weakening strength is determined as the candidate grinding wheel configuration. The grinding wheel configuration in the overall geometric model of the grinding system is updated to the candidate grinding wheel configuration to obtain the replaced overall geometric model of the grinding system; A grinding fluid nozzle model was added to the overall geometric model of the replaced grinding system, and mesh generation and physical parameter settings were performed to obtain a gas-liquid two-phase flow simulation model. In the gas-liquid two-phase flow simulation model, multiple sets of groove size parameters are set based on the candidate grinding wheel configuration, and the effective flow rate of the grinding fluid is obtained by simulation calculation using a preset grinding fluid injection speed. Based on the effective flow rate, select the target trench parameter corresponding to the largest effective flow rate from the multiple sets of trench size parameters; The performance of a grinding wheel with the target groove parameters was verified in an experimental platform using preset grinding process parameters.

[0006] Secondly, a structured grinding wheel machining performance evaluation system for grinding optical elements is provided, the system comprising: The model building module is used to construct a structured grinding wheel model with multiple groove configurations and an overall geometric model of the grinding system based on the target processing object and processing environment of fused silica optical element grinding. The model conversion module is used to perform mesh generation and physical parameter setting on the overall geometric model of the grinding system, so as to convert the overall geometric model of the grinding system into a three-dimensional airflow field simulation model that can be used for mathematical calculations. The configuration screening module is used to calculate the air barrier weakening strength of each group of groove configurations based on the three-dimensional airflow field simulation model, and to determine the groove configuration with the highest air barrier weakening strength as the candidate grinding wheel configuration. The configuration replacement module is used to update the grinding wheel configuration in the overall geometric model of the grinding system to the candidate grinding wheel configuration, so as to obtain the replaced overall geometric model of the grinding system; The parameter setting module is used to add a grinding fluid nozzle model to the overall geometric model of the replaced grinding system, and to perform mesh generation and physical parameter setting to obtain a gas-liquid two-phase flow simulation model. The simulation calculation module is used to set multiple sets of groove size parameters based on the candidate grinding wheel configuration in the gas-liquid two-phase flow simulation model, and to perform simulation calculations using a preset grinding fluid injection speed to obtain the effective flow rate of the grinding fluid. The parameter selection module is used to select the target trench parameter corresponding to the largest effective flow rate from the multiple sets of trench size parameters based on the effective flow rate. The performance verification module is used to verify the performance of a grinding wheel with the target groove parameters in an experimental platform using preset grinding process parameters.

[0007] Thirdly, a computer program product is provided, comprising: computer program code, which, when run on a computer, causes the computer to perform the method described in the first aspect or any possible implementation thereof.

[0008] Fourthly, a computer-readable storage medium is provided that stores computer program code, which, when executed on a computer, causes the computer to perform the methods described in the first aspect or any possible implementation thereof.

[0009] The present invention has the following beneficial effects: by analyzing the target processing object and processing environment of fused silica optical element grinding, it is possible to quickly construct a structured grinding wheel model with multiple groove configurations and an overall geometric model of the grinding system; by meshing and setting physical parameters of the overall geometric model of the grinding system, the overall geometric model of the grinding system can be converted into a three-dimensional airflow field simulation model that can be used for mathematical calculation, which facilitates more accurate simulation evaluation through the three-dimensional airflow field simulation model. Subsequently, based on the three-dimensional airflow field simulation model, the air barrier weakening strength of each group of groove configurations was calculated. The groove configuration with the highest weakening strength was determined as the candidate grinding wheel configuration, and the grinding wheel configuration in the overall geometric model was updated to the candidate grinding wheel configuration, resulting in the overall geometric model of the replaced grinding system. A grinding fluid nozzle model was added to the overall geometric model of the replaced grinding system, and meshing and physical parameter settings were performed to obtain a gas-liquid two-phase flow simulation model. In the gas-liquid two-phase flow simulation model, multiple sets of groove size parameters were set based on the candidate grinding wheel configurations, and simulation calculations were performed using a preset grinding fluid injection speed to obtain the effective flow rate of the grinding fluid. In this way, the initial selection of the grinding wheel configuration was completed first with the air barrier weakening effect as an indicator, and then the parameter optimization was completed with the effective flow rate of the grinding fluid as the core. This not only revealed the influence mechanism of the groove structure on the flow field characteristics of the grinding zone, but also avoided the blindness of traditional empirical design, greatly improving the accuracy and rationality of the structured grinding wheel design. Finally, based on the effective flow rate, a target groove parameter is selected from the multiple sets of groove size parameters; and the performance of the grinding wheel with the target groove parameter is verified in the experimental platform using preset grinding process parameters. In this way, by combining the flow field simulation results with the measured data from the grinding experiment, a multi-dimensional comprehensive evaluation system is constructed, realizing a quantitative evaluation of the processing performance of structured grinding wheels. Simultaneously, the accuracy and reliability of the simulation evaluation method are verified. The research results can directly guide the engineering practice of precision grinding of fused silica optical components, effectively improving the grinding quality and processing efficiency of large-size, complex curved fused silica components. Attached Figure Description

[0010] To more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0011] Figure 1 This is a schematic diagram illustrating the implementation process of a structured grinding wheel machining performance evaluation method for optical element grinding, provided in an embodiment of the present invention. Figure 2 The structured grinding wheel models for different structured grinding wheels provided in the embodiments of the present invention; Figure 3 This is a schematic diagram illustrating another implementation of the structured grinding wheel processing performance evaluation method for grinding optical components provided in this embodiment of the invention; Figure 4 This is a schematic diagram of the three-dimensional airflow field simulation model of the grinding zone provided in an embodiment of the present invention; Figure 5 This is a pressure field distribution cloud map of the workpiece surface under the action of different grinding wheels, provided in an embodiment of the present invention. Figure 6 These are air pressure variation curves along the centerline of different grinding wheel workpieces provided in embodiments of the present invention; Figure 7 The effective flow rate under different trench parameter variations provided in the embodiments of the present invention; Figure 8 This is a schematic diagram of the grinding experiment provided in an embodiment of the present invention; Figure 9 This is a comparison chart of grinding forces at different grinding wheel speeds and grinding depths provided in an embodiment of the present invention; Figure 10 This is a comparison chart of grinding temperatures at different grinding wheel speeds and grinding depths provided in an embodiment of the present invention; Figure 11 This is a comparison chart of workpiece roughness under different grinding wheel speeds and grinding depths provided in an embodiment of the present invention; Figure 12 This is a schematic diagram of the composition of a structured grinding wheel performance evaluation system for grinding optical components, provided in an embodiment of the present invention. Figure 13 This is a schematic diagram of the structure of a computer block device provided in an embodiment of the present invention. Detailed Implementation

[0012] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, the following, in conjunction with the accompanying drawings and preferred embodiments, details the specific implementation, structure, features, and effects of a structured grinding wheel machining performance evaluation method for optical element grinding proposed according to the present invention. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. Furthermore, specific features, structures, or characteristics in one or more embodiments may be combined from any suitable form.

[0013] In the description of the embodiments of the present invention, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present invention, "multiple" means two or more.

[0014] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature.

[0015] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0016] The following description, in conjunction with the accompanying drawings, details a specific scheme for evaluating the machining performance of a structured grinding wheel for grinding optical components, provided by this invention. For example... Figure 1 The diagram shown is a schematic flowchart of a method for evaluating the machining performance of a structured grinding wheel for grinding optical components, provided by an embodiment of the present invention. The method includes: 101. Based on the target processing object and processing environment of fused silica optical element grinding, a structured grinding wheel model with multiple groove configurations and an overall geometric model of the grinding system are constructed.

[0017] Here, a structured grinding wheel model with multiple groove configurations is as follows: Figure 2 As shown, these include: straight grooves, inclined grooves, and V-grooves, etc. In Figure 2 middle, The groove angle is represented by TD, the groove width by d, and the groove depth by d. The target object to be processed is the workpiece to be processed, such as a fused silica optical element. The processing environment includes processing tools and processing parameters. The processing tools are structured grinding wheels, which have grooves of specific geometric shapes (such as straight grooves, inclined grooves, and V-grooves) designed on their surfaces to improve grinding performance. Processing parameters include: grinding clearance, which is the minimum clearance between the grinding wheel and the workpiece, set in the range of 0.1 to 1 mm, a key geometric parameter for flow field simulation; and process variables, which are the effects of different grinding wheel speeds (e.g., 500 to 2000 rpm) and grinding depths (e.g., 100 to 400 micrometers) on the processing effect in subsequent experimental verification. In a specific example, the machining environment includes: a grinding wheel with a diameter of 400 mm and a width of 25 mm; a minimum grinding clearance between the grinding wheel and the target workpiece set to 0.1~1 mm; the target workpiece being located directly below the grinding wheel; and a computational domain measuring 500 mm × 450 mm × 25 mm. This configuration allows for better performance of the constructed simulation model.

[0018] In some possible implementations, the above steps can be achieved through... Figure 3 The steps shown are to be implemented as follows: 301. Obtain a baseline model that satisfies the target processing object and processing environment.

[0019] Here, the reference model is the physical model of the workpiece (i.e., the target machining object) and the grinding wheel that meets the specific parameters set for the target machining object and the machining environment.

[0020] In some possible implementations, the grinding wheel diameter is set to 400 mm and the width to 25 mm, based on parameters in the machining environment. Finally, a geometric model of the workpiece (representing a fused silica optical element) is created beneath the grinding wheel to obtain the workpiece model. The workpiece is then placed directly beneath the grinding wheel. The positions of the workpiece and the grinding wheel are adjusted to maintain a minimum grinding clearance between the wheel and the workpiece between 0.1 and 1 mm; this clearance is the core area for subsequent fluid simulation.

[0021] 302. Based on the groove parameters corresponding to the multiple sets of groove configurations, the reference model is parametrically configured to obtain the structured grinding wheel model.

[0022] Here, the groove configuration of the structured grinding wheel includes three basic configurations: straight groove, inclined groove, and V-groove; the core geometric parameters of the groove include groove width, groove angle, groove depth, and groove coefficient, wherein the groove coefficient is defined as the percentage of the effective area of ​​the grinding wheel participating in grinding to the total surface area of ​​the grinding wheel.

[0023] In this way, a cylinder (i.e., a reference model) is first built, and then an array of cuts is performed on the surface according to the defined parameters (width, depth, angle, coefficient) to generate straight / oblique / V-shaped grooves. Finally, it is assembled with the workpiece and a 500×450×25mm computational domain. By changing the parameter combination in the second step, a variety of different structured grinding wheel models can be quickly generated for subsequent comparative simulation.

[0024] 303. Based on each structured grinding wheel model, the target machining object, and the machining environment, construct the overall geometric model of the grinding system.

[0025] In some possible implementations, firstly, a computational domain is obtained that surrounds the grinding wheel and covers the grinding area of ​​the target object being processed; then, the computational domain, any structured grinding wheel model, and the reference model corresponding to the processing environment are assembled to obtain the overall geometric model of the grinding system.

[0026] Here, a cuboid space (fluid domain) surrounding the grinding wheel and workpiece is created. This cuboid space is then sized to 500mm × 450mm × 25mm to ensure complete coverage of the grinding area, thus obtaining the computational domain that surrounds the grinding wheel and covers the grinding area of ​​the target object. Specifically, a three-dimensional airflow simulation model is built using Fluent software, with the grinding wheel diameter set to 400mm and width to 25mm, the workpiece positioned directly below the grinding wheel, and the minimum grinding clearance between the grinding wheel and workpiece fixed at 0.3mm. The computational domain size is set to 500mm × 450mm × 25mm, completely covering the grinding area of ​​the grinding wheel and workpiece. Then, based on the baseline model, the computational domain and various structured grinding wheel models are assembled to obtain the overall geometric model of the grinding system. During assembly, one structured grinding wheel model is replaced each time, while other parameters remain unchanged. In this way, by assembling the optimized structured grinding wheel model, workpiece model, and computational domain, a relatively accurate overall geometric model of the grinding system can be obtained.

[0027] 102. Mesh the overall geometric model of the grinding system and set the physical parameters to convert the overall geometric model of the grinding system into a three-dimensional airflow field simulation model that can be used for mathematical calculations.

[0028] Here, for the grinding conditions of fused silica optical elements, a structured grinding wheel with various groove configurations and corresponding three-dimensional geometric models are designed. At the same time, combined with the target processing object and grinding conditions, an overall geometric model of the grinding system including the workpiece, the computing domain and the grinding fluid supply unit is constructed. In some possible implementations, firstly, multiple pre-defined unstructured meshes of different densities are used to fill the overall geometric model of the grinding system. The minimum grinding clearance between the grinding wheel and the target workpiece in the overall geometric model of the grinding system is then refined, resulting in multiple refined overall geometric models corresponding to the pre-defined unstructured meshes. For example, unstructured meshes are used to fill the model to adapt to the complex shape of the computational domain of the overall geometric model of the grinding system, and local refinement is performed in the region of the minimum grinding clearance (0.1~1mm) between the grinding wheel and the workpiece (i.e., the target workpiece). Then, boundary layer processing is performed, setting five boundary layer meshes on the grinding wheel surface and the workpiece wall to accurately capture the fluid velocity gradient and viscous effects near the wall.

[0029] Secondly, in the multiple encrypted overall geometric models, the rotating fluid domain and the surrounding fluid domain that rotate synchronously with the grinding wheel are obtained respectively; wherein, the surrounding fluid domain is used to characterize the spatial region occupied and flowing by fluid in the overall geometric model of the grinding system; Next, error and complexity calculations are performed on the rotating domain and surrounding fluid domain under different preset grids to obtain the calculation results corresponding to each preset grid. For example, airflow field simulation calculations are performed on each of the above-mentioned grid models using the same physical model and boundary conditions. It is ensured that the turbulence model, boundary conditions (such as grinding wheel linear velocity of 60 m / s, pressure outlet, etc.), and convergence criteria corresponding to all grids are completely consistent. The physical quantity most sensitive to the grid is selected as the monitoring object. In this embodiment of the invention, the core monitoring index is the sum of the absolute values ​​of the peak positive and negative pressures on the workpiece surface (i.e., the weakening strength of the air barrier layer).

[0030] Next, among the preset grids, the optimal preset grid that satisfies the preset conditions is selected. Finally, the optimal preset grid and preset physical parameters are encapsulated to obtain the three-dimensional airflow field simulation model. For example, the sum of the absolute values ​​of the positive and negative pressure peaks calculated under different grid numbers is plotted as a curve to observe its changing trend. In a specific example, when the grid is sparse (e.g., 200,000), the calculation results fluctuate greatly and the accuracy is insufficient. As the number of grids increases (e.g., from 300,000 to 450,000), the values ​​gradually tend to stabilize. When the number of grids continues to increase (e.g., from 450,000 to 600,000 or 800,000), if the change in the key indicators (relative error) is less than the preset threshold (usually 1% to 5% in engineering), it is considered that the calculation results are no longer significantly affected by the grid density. Finally, the number of grids that meets the accuracy requirements and has the lowest calculation cost is selected. For example, when the number of grids reaches 450,000, the value of the peak pressure of the air barrier layer has already tended to stabilize (i.e., grid independence has been achieved). Continuing to increase the number of grids may slightly improve the accuracy, but it will significantly increase the calculation time, resulting in low cost-effectiveness. Therefore, the preset unstructured grid of 450,000 grids was determined as the optimal preset grid for all subsequent airflow field simulations and gas-liquid two-phase flow simulations.

[0031] In some possible implementations, a gas-liquid two-phase flow simulation model is established based on the volume of fluid (VOF) fraction method. Physical parameters and grinding fluid supply boundary conditions are set, and the distribution law of grinding fluid in the grinding zone under different grinding wheel action is simulated and analyzed. The effective flow rate of grinding fluid is used as the core index to complete the quantitative evaluation of the cooling and lubrication performance of the grinding wheel to be evaluated and the optimization of groove parameters.

[0032] The rotating fluid domain is the fluid (air) region in the overall geometric model of the grinding system that is set to rotate along with the grinding wheel. The surrounding fluid domain is used to characterize the spatial region occupied and flowing by fluid in the overall geometric model of the grinding system. After obtaining the rotating fluid domain and the surrounding fluid domain, a mesh generation strategy of "overall unstructured mesh + local refinement of grinding gap" is adopted to set boundary layer meshes near the grinding wheel and workpiece wall to complete mesh independence verification and determine the optimal preset mesh.

[0033] In some possible implementations, firstly, multiple sets of preset unstructured meshes with different densities are constructed; secondly, simulation calculations are performed under identical conditions, using the same physical model (i.e., the overall geometric model of the grinding system), boundary conditions (such as grinding wheel speed, pressure outlet, etc.), and solver settings, respectively, to calculate the above three sets of preset unstructured meshes; thirdly, key simulation results are compared, and one or more physical quantities crucial to the research are selected as evaluation indicators. In this embodiment of the invention, key indicators may include: peak positive and negative pressure on the workpiece surface, airflow velocity at a specific location in the grinding zone, thickness or distribution pattern of the air barrier layer, etc. Finally, the optimal preset mesh is determined by error analysis, and the relative errors of key indicators between meshes of different densities are calculated.

[0034] In a specific example, at least three preset unstructured meshes are created. These preset unstructured meshes are based on the same geometry and meshing strategy, but differ in the total number of meshes, including: Coarse mesh: the fewest meshes, fastest computation speed, but potentially insufficient accuracy; Medium mesh: moderate number of meshes; Fine mesh: the most meshes, longest computation time, usually used as a benchmark for accuracy comparison.

[0035] Calculating the relative error of key metrics between grids of different densities can be done by comparing the results of calculating "medium-density" grids with those of "fine-density" grids. The criteria for judgment include: if the error between the calculation results of "medium-density" and "fine-density" grids is very small (e.g., less than 1% to 5%), the calculation results can be considered to have achieved "grid independence," and the medium-density grid can be ultimately selected as the "optimal grid" for all subsequent simulations. This is because the medium-density grid maximizes the saving of computational resources and time costs while ensuring computational accuracy.

[0036] In some possible implementations, after determining the optimal preset mesh, the optimal preset mesh is applied to the overall geometric model of the grinding system, and boundary conditions (i.e., preset physical parameters) are set, including: setting the workpiece surface as a stationary, non-slip wall, setting the outer surface of the computational domain as a standard atmospheric pressure outlet, setting the grinding wheel surface as a moving wall rotating about its central axis, and setting the groove region as a rotating fluid domain that rotates synchronously with the grinding wheel; finally, the solver is set, including: using a renormalization group (RNG). The turbulence model, pressure-based solver, and SIMPLE (SIMPLEConsistent, SIMPLE) consistent algorithm are used to obtain the geometric model of the airflow field simulation in the grinding zone (i.e., the three-dimensional airflow field simulation model).

[0037] Among some possible implementations, a strategy of "overall unstructured mesh + local fine-tuning of grinding gap" is adopted. The computational domain is filled with an unstructured mesh, and the minimum clearance region between the grinding wheel and the workpiece is locally fine-tuned. Five boundary layer meshes are set on the grinding wheel and workpiece walls. After mesh independence verification, the optimal preset mesh size is determined to be 450,000. The workpiece surface is set as a stationary, non-slip wall, and the five outer surfaces of the computational domain are all set as standard atmospheric pressure (101325 Pa) pressure outlets. The grinding wheel surface is set as a moving wall rotating around its central axis, with a linear velocity of 60 m / s. The groove region is set as a rotating fluid domain that rotates synchronously with the grinding wheel. A turbulence model and a pressure-based steady-state solver are used. The pressure-velocity coupling uses the SIMPLEC algorithm. The momentum equation, turbulent kinetic energy k-equation, and turbulent dissipation rate equation are all discretized using a second-order upwind scheme. The convergence criterion is set as the residuals of all variables decreasing to 10. -6 The following is how the three-dimensional airflow field simulation model is obtained; the three-dimensional airflow field simulation model of the grinding zone is as follows: Figure 4 As shown, in Figure 4 The image shows the grinding wheel, the air barrier layer, and preset physical parameters (such as pressure outlet, workpiece wall, etc.).

[0038] 103. Based on the three-dimensional airflow field simulation model, the air barrier weakening strength of each group of groove configurations is calculated, and the groove configuration with the highest air barrier weakening strength is determined as the candidate grinding wheel configuration.

[0039] Here, the weakening strength of the air barrier layer is the sum of the absolute values ​​of the positive and negative pressure peaks on the workpiece surface. The weakening strength of the air barrier layer characterizes the degree to which the grinding wheel corresponding to each groove configuration weakens the air barrier layer. The high-speed rotating grinding wheel forms a high-pressure air film (i.e., the air barrier layer) in the grinding zone, hindering the entry of grinding fluid. The smaller the sum of the positive and negative pressure peaks, the weaker the air barrier layer, meaning a higher weakening strength, and thus a more stable airflow. The groove configuration with the highest weakening strength is the weakest air barrier layer, indicating that the grinding wheel corresponding to this groove configuration has a superior weakening effect on the air barrier layer. Therefore, the groove configuration with the highest weakening strength is identified as the candidate grinding wheel configuration.

[0040] After constructing a three-dimensional airflow field simulation model, the pressure and velocity field characteristics of different grinding wheels were analyzed using Computational Fluid Dynamics (CFD) airflow field simulation to complete the initial selection of grinding wheel configurations, thereby screening out candidate grinding wheel configurations with the highest weakening strength. A three-dimensional airflow field simulation model of the grinding zone was established based on the CFD method, completing mesh generation and independence verification, boundary conditions and solver settings. The pressure and velocity field characteristics of the grinding zone under the action of different grinding wheels were obtained through simulation calculations. Using the air barrier weakening effect as the core indicator, the airflow field performance of the grinding wheel to be evaluated was quantitatively evaluated and the initial configuration was selected. The pressure field of the grinding zone under the action of different grinding wheels is shown below. Figure 5 As shown, Figure 5 Figure (a) shows the pressure field distribution cloud map of the workpiece surface under the action of a grooveless grinding wheel, Figure (b) shows the pressure field distribution cloud map of the workpiece surface under the action of a straight groove grinding wheel, Figure (c) shows the pressure field distribution cloud map of the workpiece surface under the action of a slanted groove grinding wheel, and Figure (d) shows the pressure field distribution cloud map of the workpiece surface under the action of a V-groove grinding wheel.

[0041] In some possible implementations, within the three-dimensional airflow field simulation model, based on the same mesh density, each group of groove configurations is compared and analyzed. Airflow field calculations are then performed on each group of groove configurations in the three-dimensional airflow field simulation model to obtain the air barrier weakening intensity of each group of groove configurations. For example, after constructing the three-dimensional airflow field simulation model, during the simulation process, the mesh density is kept constant, and the groove configurations are replaced one by one to calculate the air barrier weakening intensity under each groove configuration. In this way, only the groove configuration is a variable during the simulation process, while other parameters are fixed, enabling accurate calculation of the air barrier weakening intensity of each group of groove configurations, thus facilitating more accurate selection of candidate grinding wheel configurations.

[0042] In some possible implementations, a replaced three-dimensional airflow field simulation model is obtained by replacing the current groove configuration in the three-dimensional airflow field simulation model with any groove configuration; and in the replaced three-dimensional airflow field simulation model, the absolute values ​​of the peak positive and negative pressures on the surface of the target processing object are calculated; finally, the absolute values ​​of the peak positive and negative pressures are summed to obtain the air barrier weakening strength of each group of groove configurations.

[0043] Here, the quantitative evaluation index of the air barrier weakening performance includes the sum of the absolute values ​​of the peak values ​​of positive and negative pressure on the workpiece surface. The smaller the sum of the absolute values ​​of the peak values ​​of positive and negative pressure on the workpiece surface, the better the weakening effect of the grinding wheel on the air barrier.

[0044] In some possible implementations, the airflow velocity distribution curve and airflow pressure distribution curve along the radial direction of the grinding wheel in the grinding zone are extracted; the maximum airflow velocity value and boundary layer thickness at the center of the grinding zone under each configuration are calculated; the groove configuration with the smallest maximum airflow velocity value and the thinnest boundary layer thickness is determined as the configuration with the highest air barrier weakening strength, and this is identified as the structured grinding wheel model. The air pressure variation curves along the workpiece centerline for different grinding wheels are shown below. Figure 6 As shown, curve 601 is the air pressure change curve of the center line of the workpiece of the straight groove grinding wheel, curve 602 is the air pressure change curve of the center line of the workpiece of the ungrooved grinding wheel, curve 603 is the air pressure change curve of the center line of the workpiece of the inclined groove grinding wheel, and curve 604 is the air pressure change curve of the center line of the workpiece of the V-groove grinding wheel.

[0045] 104. Update the grinding wheel configuration in the overall geometric model of the grinding system to the candidate grinding wheel configuration to obtain the replaced overall geometric model of the grinding system.

[0046] Here, keeping the geometric position of the grinding area and the workpiece unchanged, the current grinding wheel model in the overall geometric model of the grinding system is replaced with the candidate grinding wheel configuration to obtain the replaced overall geometric model of the grinding system.

[0047] 105. A grinding fluid nozzle model is added to the overall geometric model of the replaced grinding system, and mesh generation and physical parameter settings are performed to obtain a gas-liquid two-phase flow simulation model.

[0048] Here, a nozzle geometric model is established at the tangential or normal position of the grinding wheel (i.e., a grinding fluid nozzle model is added). The grinding fluid nozzle model includes the nozzle orifice diameter and the distance from the nozzle to the workpiece. Boolean operations are performed on the obtained model to remove overlapping areas, forming a deduplicated model that includes the grinding wheel, workpiece, nozzle, and fluid domain. Then, the deduplicated model is mathematically transformed to obtain a gas-liquid two-phase flow simulation model that can be used for simulation calculations.

[0049] In some possible implementations, firstly, a grinding fluid nozzle model is established at the tangential or normal position of the grinding wheel in the replaced overall geometric model of the grinding system to obtain an updated model; wherein, the grinding fluid nozzle model includes: nozzle orifice diameter and nozzle-to-workpiece distance parameters; then, overlapping areas are removed from the updated model to form a deduplicated model including the grinding wheel, the target machining object, the nozzle, and the fluid domain; finally, the deduplicated model is meshed and physical parameters are set to obtain a gas-liquid two-phase flow simulation model.

[0050] Here, based on the geometric model of the airflow field simulation, a grinding fluid nozzle structure is added and placed at the minimum clearance inlet of the grinding zone to establish the model. Next, mesh generation is performed, following the mesh generation strategy used in the airflow field simulation. Secondary local refinement is applied to the nozzle outlet and grinding clearance regions to verify mesh independence. Then, boundary conditions are set, including: the grinding fluid nozzle is set as a velocity inlet with an inlet velocity of 3 m / s; the grinding fluid integral number at the inlet is 1; the outer surface of the computational domain is set as a standard atmospheric pressure outlet; and the workpiece and grinding wheel wall settings are consistent with the airflow field simulation. Finally, a pressure-based unsteady double-precision solver is used, and the turbulence model is selected from the RNG. The turbulence model and enhanced wall function were used to realize the mesh generation and physical parameter setting of the deduplicated model, resulting in a gas-liquid two-phase flow simulation model.

[0051] In some possible implementations, the interaction between the grinding fluid and air is defined using an Euler-Euler multiphase flow model or a discrete phase model. Then, the grinding fluid is set as the discrete phase and the air as the continuous phase, and the density, viscosity, and surface tension coefficient of the grinding fluid are set. Finally, the nozzle outlet is defined as the velocity inlet boundary, and the initial injection velocity vector and volume fraction of the grinding fluid are set, so that the gas-liquid two-phase flow simulation model can be obtained quickly and accurately.

[0052] 106. In the gas-liquid two-phase flow simulation model, multiple sets of groove size parameters are set based on the candidate grinding wheel configuration, and the effective flow rate of the grinding fluid is obtained by simulation calculation using a preset grinding fluid injection speed.

[0053] Here, the controlled variable method is used. Based on the candidate grinding wheel configuration, multiple sets of combined parameters (i.e., multiple sets of groove size parameters) are set between groove width, groove depth, and groove spacing. Then, under each set of parameters, the motion trajectory of grinding fluid particles in the flow field is tracked, and the number or volume of grinding fluid particles entering the grinding contact area between the grinding wheel and the workpiece is counted. Finally, the effective flow rate of the grinding fluid is calculated, which is the ratio of the grinding fluid flow rate entering the grinding contact area to the total flow rate of the nozzle. The effective flow rate under different groove size parameters is shown in the figure. Figure 7 As shown, curve 701 represents the effective flow rate under different trench widths, curve 702 represents the effective flow rate under different trench angles, curve 703 represents the effective flow rate under different trench depths, and curve 704 represents the effective flow rate under different trench coefficients.

[0054] 107. Based on the effective flow rate, select the target trench parameter corresponding to the largest effective flow rate from the multiple sets of trench size parameters.

[0055] Here, the effective flow rate is the ratio of the mass flow rate of the grinding fluid passing through the minimum grinding gap to the mass flow rate at the nozzle inlet. A higher effective flow rate indicates better cooling and lubrication performance of the grinding wheel. For the multiple sets of effective grinding fluid flow rates obtained, the highest effective flow rate is selected, and the groove size parameter corresponding to this highest effective flow rate is determined as the target groove parameter.

[0056] In some embodiments, the cooling and lubrication performance of the grinding wheel is evaluated by the effective flow rate of the grinding fluid in the grinding zone and the uniformity of the grinding fluid distribution in the grinding zone. In some possible implementations, any set of groove size parameters and a preset grinding fluid injection velocity are input into the gas-liquid two-phase flow simulation model to obtain the distribution map of the grinding fluid in the grinding zone, the mass flow rate of the grinding fluid at the minimum grinding gap, and the mass flow rate at the nozzle inlet under the given groove size parameters. The ratio between the mass flow rate of the grinding fluid at the minimum grinding gap and the mass flow rate at the nozzle inlet is then determined as the effective flow rate of the grinding fluid. Subsequently, the cooling and lubrication performance of the candidate grinding wheel configuration is evaluated by the ratio between the mass flow rate of the grinding fluid at the minimum grinding gap and the mass flow rate at the nozzle inlet, as well as the uniformity index of the grinding fluid in the grinding zone represented by the distribution map.

[0057] The quantitative evaluation indicators of cooling and lubrication performance include the effective flow rate of grinding fluid in the grinding zone and the uniformity of grinding fluid distribution in the grinding zone. The effective flow rate is the ratio of the mass flow rate of grinding fluid through the minimum grinding gap to the mass flow rate at the nozzle inlet. A higher effective flow rate indicates better cooling and lubrication performance of the grinding wheel.

[0058] 108. The performance of the grinding wheel with the target groove parameters is verified in the experimental platform using preset grinding process parameters.

[0059] First, an experimental platform was built based on a CNC precision grinding machine. A three-dimensional force sensor was used to collect grinding force signals, and a T-type thermocouple was used to collect the temperature in the grinding zone. The surface roughness of the workpiece after machining was measured using a confocal white light interferometer. Second, multiple sets of grinding process parameters were designed with wheel speed and grinding depth as variables. Parallel comparative experiments were conducted using grooveless grinding wheels and optimized structured grinding wheels. Each set of experiments was repeated three times and the average value was taken. Finally, the grinding performance of different grinding wheels was compared using the core indicators of grinding force reduction, grinding temperature reduction, and workpiece surface roughness to verify the accuracy of the flow field simulation results and the effectiveness of the simulation evaluation method.

[0060] In some possible implementations, the experimental principles in the embodiments of the present invention, such as Figure 8 As shown in Figure (a), a force measuring instrument is placed on the experimental platform. A fixture, workpiece, thermocouple, grinding wheel, transmitter, data acquisition card and computer are placed on the force measuring instrument in sequence. The force measuring instrument and the data acquisition card are linearly connected. Figure 8Figure (b) shows the physical connection between the workpiece, the force gauge, the thermocouple, and the grinding wheel.

[0061] In a specific example, the sum of the absolute values ​​of the peak positive and negative pressures on the workpiece surface was used as the core evaluation index to compare the air barrier weakening effects of four types of grinding wheels. Simulation results show that the skewed groove grinding wheel has the smallest sum of the absolute values ​​of the peak positive and negative pressures, and the air barrier weakening effect is the best. Therefore, the skewed groove grinding wheel is selected as the core configuration for subsequent optimization research. Based on the three-dimensional airflow field simulation model, a grinding fluid nozzle with a rectangular cross-section of the same width as the grinding wheel was added, and the nozzle was placed at the minimum gap inlet of the grinding zone; the nozzle outlet and the grinding gap area were locally refined a second time, and the number of grids was determined to be 450,000 after the grid independence verification. The nozzle inlet is set as a velocity inlet with an inlet velocity of 3 m / s, and the grinding fluid integral is set to 1. The outer surface of the calculation domain is set as a standard atmospheric pressure outlet, the workpiece surface is set as a stationary, non-slip wall, the grinding wheel surface is set as a rotating wall, and the linear velocity is fixed at 30 m / s. A pressure-based unsteady double-precision solver was used, and the turbulence model was the RNG k-ε model with enhanced wall function. Air was defined as the main phase and 20℃ water-based grinding fluid as the second phase. A gravitational acceleration of 9.81 m / s² was set along the negative Y-axis. The gas-liquid interface was tracked by the volume fraction equation. The time step was set to (1e-5) s, and the total calculation time was 0.2 s until the flow field stabilized. Using the effective flow rate of grinding fluid as the core indicator, the influence of groove parameters on the distribution of grinding fluid was systematically analyzed, and the optimal parameter combination for the skewed groove grinding wheel was finally determined: groove width 3mm, groove angle 45°, groove depth 3mm, and groove coefficient 70%; under these parameters, the effective flow rate of grinding fluid reached 16.5%, which was the best among all parameter groups.

[0062] An experimental platform was built based on a UPG60 CNC precision grinding machine. An LZ-SWL6 three-dimensional force sensor was used to collect grinding force, and a set-screw method combined with a T-type thermocouple was used to collect temperature in the grinding zone. A Sensofar confocal white light interferometer was used to measure the surface roughness of the ground workpiece. Figure 9 As shown, Figure 9 In the figure, (a) represents the grinding force of the fluteless grinding wheel and the skewed grinding wheel at different grinding wheel speeds. Figure 9 (b) in the figure represents the grinding force of the grooveless grinding wheel and the skewed grinding wheel at different grinding depths.

[0063] The experimental workpiece was JSG2 fused silica optical glass with dimensions of 50mm×50mm×50mm; the experimental grinding wheels were a grooveless grinding wheel and a grooved grinding wheel with optimized parameters, and the abrasive was 120# diamond; multiple sets of experiments were designed with grinding wheel speed of 500~2000 rpm and grinding depth of 100~400 micrometers as variables, and each set of experiments was repeated 3 times and the average value was taken.

[0064] Using the reduction in grinding force, the reduction in grinding temperature, and the surface roughness of the workpiece as core indicators, the grinding performance of different grinding wheels was compared. Test results showed that the optimized skewed groove grinding wheel reduced the normal grinding force by 28.7% to 41.5% compared to the ungrooved grinding wheel, and achieved a maximum temperature reduction of 27.5% in the grinding zone. After fine grinding of planar components, the PV value converged to 7 micrometers and the RMS value to 1.29 micrometers, demonstrating the best overall machining performance. This result highly matched the simulation evaluation results, verifying the effectiveness of the embodiments of the present invention. Grinding temperatures at different grinding wheel speeds and grinding depths are as follows: Figure 10 As shown, Figure 10 In the figure, (a) represents the grinding temperature of fluteless grinding wheels and skewed grinding wheels at different grinding wheel speeds. Figure 10 (b) represents the grinding temperature of fluteless and skewed flute grinding wheels at different grinding depths. The workpiece surface roughness at different wheel speeds and grinding depths is shown in the figure. Figure 11 As shown, Figure 11 In the figure, (a) represents the workpiece roughness of the fluteless grinding wheel and the skewed grinding wheel at different grinding wheel speeds. Figure 11 (b) in the figure represents the workpiece roughness of the grooveless grinding wheel and the skewed grinding wheel at different grinding depths.

[0065] This invention provides a structured grinding wheel machining performance evaluation system for optical element grinding, such as... Figure 12 As shown, the system 1200 includes: Model building module 1201 is used to build a structured grinding wheel model with multiple groove configurations and an overall geometric model of the grinding system based on the target processing object and processing environment of fused silica optical element grinding. The model conversion module 1202 is used to perform mesh generation and physical parameter setting on the overall geometric model of the grinding system, so as to convert the overall geometric model of the grinding system into a three-dimensional airflow field simulation model that can be used for mathematical calculations. The configuration screening module 1203 is used to calculate the air barrier weakening strength of each group of groove configurations based on the three-dimensional airflow field simulation model, and to determine the groove configuration with the highest air barrier weakening strength as the candidate grinding wheel configuration. Configuration replacement module 1204 is used to update the grinding wheel configuration in the overall geometric model of the grinding system to the candidate grinding wheel configuration, so as to obtain the replaced overall geometric model of the grinding system; The parameter setting module 1205 is used to add a grinding fluid nozzle model to the overall geometric model of the replaced grinding system, and to perform mesh generation and physical parameter setting to obtain a gas-liquid two-phase flow simulation model. The simulation calculation module 1206 is used to set multiple sets of groove size parameters based on the candidate grinding wheel configuration in the gas-liquid two-phase flow simulation model, and to perform simulation calculations using a preset grinding fluid injection speed to obtain the effective flow rate of the grinding fluid. The parameter selection module 1207 is used to select the target trench parameter corresponding to the largest effective flow rate from the multiple sets of trench size parameters based on the effective flow rate. The performance verification module 1208 is used to verify the performance of a grinding wheel with the target groove parameters in an experimental platform using preset grinding process parameters.

[0066] In some possible implementations, the model building module 1201 is further configured to obtain a reference model that satisfies the target machining object and the machining environment; to parametrically configure the reference model based on the groove parameters corresponding to the multiple sets of groove configurations to obtain the structured grinding wheel model; and to construct the overall geometric model of the grinding system based on each structured grinding wheel model, the target machining object, and the machining environment.

[0067] In some possible implementations, the model building module 1201 is further configured to obtain a computational domain that surrounds the grinding wheel and covers the grinding area of ​​the target machining object; and to assemble the computational domain, any structured grinding wheel model, and the reference model corresponding to the machining environment to obtain the overall geometric model of the grinding system.

[0068] In some possible implementations, the model conversion module 1202 is further configured to fill the overall geometric model of the grinding system with multiple preset unstructured meshes of different densities, and to refine the minimum grinding gap between the grinding wheel and the target workpiece in the overall geometric model of the grinding system, thereby obtaining multiple refined overall geometric models corresponding to the multiple preset unstructured meshes; in the multiple refined overall geometric models, the rotating fluid domain and the surrounding fluid domain that rotate synchronously with the grinding wheel are obtained respectively; wherein, the surrounding fluid domain is used to characterize the spatial region occupied and flowing by fluid in the overall geometric model of the grinding system; the error and complexity are calculated for the rotating domain and the surrounding fluid domain under different preset meshes, respectively, to obtain the calculation results corresponding to each preset mesh; among the preset meshes, the optimal preset mesh whose calculation results meet preset conditions is selected; the optimal preset mesh and preset physical parameters are encapsulated to obtain the three-dimensional airflow field simulation model.

[0069] In some possible implementations, the configuration screening module 1203 is also used to compare and analyze each group of groove configurations in the three-dimensional airflow field simulation model based on the same grid density; and to perform airflow field calculations on each group of groove configurations in the three-dimensional airflow field simulation model to obtain the air barrier weakening strength of each group of groove configurations.

[0070] In some possible implementations, the configuration screening module 1203 is further configured to replace the current groove configuration in the three-dimensional airflow field simulation model with any groove configuration to obtain a replaced three-dimensional airflow field simulation model; in the replaced three-dimensional airflow field simulation model, calculate the absolute values ​​of the peak positive and negative pressures on the surface of the target processing object; sum the absolute values ​​of the peak positive and negative pressures to obtain the air barrier weakening strength of each group of groove configurations.

[0071] In some possible implementations, the parameter setting module 1205 is further configured to establish a grinding fluid nozzle model at the tangential or normal position of the grinding wheel in the replaced overall geometric model of the grinding system, thereby obtaining an updated model; wherein, the grinding fluid nozzle model includes: nozzle orifice diameter and nozzle-to-workpiece distance parameters; the updated model is subjected to overlapping region removal to form a deduplicated model including the grinding wheel, the target machining object, the nozzle, and the fluid domain; the deduplicated model is subjected to mesh generation and physical parameter setting to obtain a gas-liquid two-phase flow simulation model.

[0072] In some possible implementations, the simulation calculation module 1206 is further configured to input any set of groove size parameters and a preset grinding fluid injection velocity into the gas-liquid two-phase flow simulation model to obtain, under the given set of groove size parameters, the distribution map of the grinding fluid in the grinding zone, the mass flow rate of the grinding fluid at the minimum grinding gap, and the mass flow rate at the nozzle inlet; the ratio between the mass flow rate of the grinding fluid at the minimum grinding gap and the mass flow rate at the nozzle inlet is determined as the effective flow rate of the grinding fluid; based on the ratio between the mass flow rate of the grinding fluid at the minimum grinding gap and the mass flow rate at the nozzle inlet, and the uniformity index of the grinding fluid in the grinding zone represented by the distribution map, the cooling and lubrication performance of the candidate grinding wheel configuration is evaluated.

[0073] In some possible implementations, the machining environment includes: a grinding wheel with a diameter of 400 mm and a width of 25 mm; a minimum grinding clearance between the grinding wheel and the target workpiece set to 0.1~1 mm; the target workpiece being located directly below the grinding wheel; and the computational domain having dimensions of 500 mm × 450 mm × 25 mm.

[0074] Optionally, the transmission medium can be a wired link (e.g., but not limited to, coaxial cable, optical fiber, and Digital Subscriber Line (DSL)) or a wireless link (e.g., but not limited to, Wireless Fidelity (WIFI), Bluetooth, and mobile block device networks). It should be noted that the control block device provided in the above embodiments is only an example illustrating the division of the above functional modules. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the computer block device can be divided into different functional modules to complete all or part of the functions described above. Furthermore, the method embodiments provided in the above embodiments belong to the same concept, and their specific implementation processes are detailed in the method embodiments, and will not be repeated here.

[0075] Figure 13 This is a schematic diagram of the structure of a computer block device provided in an embodiment of the present invention. For example, as shown... Figure 13 As shown, the computer block device 1300 includes: a memory 1301, a processor 1302, and a computer program 1303 stored in the memory 1301 and running on the processor 1302, wherein when the processor 1302 executes the computer program 1303, the computer block device can execute any of the aforementioned methods for evaluating the machining performance of structured grinding wheels for grinding optical elements.

[0076] Furthermore, embodiments of the present invention also protect a control block device, which may include a memory and a processor. The memory stores executable program code, and the processor is used to call and execute the executable program code to perform a method for evaluating the machining performance of a structured grinding wheel for grinding optical elements provided in this embodiment of the present invention. Embodiments of the present invention can divide the control block device into functional modules based on the above method examples. For example, each module may correspond to a specific function, or two or more functions may be integrated into a processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment of the present invention is illustrative and only represents a logical functional division; in actual implementation, there may be other division methods. It should be noted that all relevant content of each step involved in the above method embodiments can be referenced to the functional description of the corresponding functional module, and will not be repeated here. It should be understood that the control block device provided in this embodiment of the present invention is used to execute the above-mentioned method for evaluating the machining performance of a structured grinding wheel for grinding optical elements, and therefore can achieve the same effect as the above-described implementation method. When using integrated units, the control block device may include a processing module and a storage module. When the control block device is applied to a block device, the processing module can be used to control and manage the actions of the block device. The storage module can be used to support the block device in executing mutual program code, etc. The processing module can be a processor or a controller, which can implement or execute various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this invention. The processor can also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of Digital Signal Processing (DSP) and a microprocessor, etc., and the storage module can be a memory.

[0077] Furthermore, the control block device provided in the embodiments of the present invention may specifically be a chip, component, or module. The chip may include a connected processor and a memory. The memory stores instructions, and when the processor calls and executes the instructions, the chip can execute the structured grinding wheel machining performance evaluation method for optical element grinding provided in the above embodiments. The embodiments of the present invention also provide a computer-readable storage medium storing computer program code. When the computer program code is run on a computer, the computer executes the aforementioned method steps to implement the structured grinding wheel machining performance evaluation method for optical element grinding provided in the above embodiments.

[0078] This invention also provides a computer program product. When the computer program product is run on a computer, it causes the computer to execute the aforementioned steps to achieve the structured grinding wheel machining performance evaluation method for optical element grinding provided in the above embodiments. The control block device, computer-readable storage medium, computer program product, or chip provided in this invention are all used to execute the corresponding methods provided above. Therefore, the beneficial effects they achieve can be referred to in the beneficial effects of the corresponding methods provided above, and will not be repeated here. Through the description of the above embodiments, those skilled in the art will understand that, for the sake of convenience and brevity, only the division of the above functional modules is used as an example. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the control block device can be divided into different functional modules to complete all or part of the functions described above. In the embodiments provided by this invention, it should be understood that the disclosed control block device and method can be implemented in other ways. For example, the control block device embodiments described above are merely illustrative. For instance, the division of modules or units is only a logical functional division; in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another control block device, or some features may be ignored or not executed. Furthermore, the shown or discussed mutual couplings, direct couplings, or communication connections may be through some interfaces; indirect couplings or communication connections between control block devices or units may be electrical, mechanical, or other forms.

[0079] It should be noted that the order of the above embodiments of the present invention is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. The processes depicted in the accompanying drawings do not necessarily require a specific or sequential order to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous. The various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. The above content is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for evaluating the machining performance of structured grinding wheels used in grinding optical components, characterized in that, The method includes: Based on the target processing object and processing environment of fused silica optical element grinding, a structured grinding wheel model with multiple groove configurations and an overall geometric model of the grinding system are constructed. The overall geometric model of the grinding system is meshed and its physical parameters are set to convert the overall geometric model of the grinding system into a three-dimensional airflow field simulation model that can be used for mathematical calculations. Based on the three-dimensional airflow field simulation model, the air barrier weakening intensity of each group of groove configurations is calculated, and the groove configuration with the highest air barrier weakening intensity is determined as the candidate grinding wheel configuration; wherein, the air barrier weakening intensity is used to characterize the degree of weakening of the air barrier layer by the grinding wheel corresponding to each group of groove configurations. The grinding wheel configuration in the overall geometric model of the grinding system is updated to the candidate grinding wheel configuration to obtain the replaced overall geometric model of the grinding system; A grinding fluid nozzle model was added to the overall geometric model of the replaced grinding system, and mesh generation and physical parameter settings were performed to obtain a gas-liquid two-phase flow simulation model. In the gas-liquid two-phase flow simulation model, multiple sets of groove size parameters are set based on the candidate grinding wheel configuration, and the effective flow rate of the grinding fluid is obtained by simulation calculation using a preset grinding fluid injection speed. Based on the effective flow rate, select the target trench parameter corresponding to the largest effective flow rate from the multiple sets of trench size parameters; The performance of a grinding wheel with the target groove parameters was verified in an experimental platform using preset grinding process parameters.

2. The method according to claim 1, characterized in that, The target machining object and machining environment based on fused silica optical element grinding are used to construct a structured grinding wheel model with multiple groove configurations and an overall geometric model of the grinding system, including: Obtain a baseline model that satisfies the target processing object and processing environment; Based on the groove parameters corresponding to the multiple sets of groove configurations, the reference model is parametrically configured to obtain the structured grinding wheel model. Based on the structured grinding wheel models, the target machining object, and the machining environment, an overall geometric model of the grinding system is constructed.

3. The method according to claim 2, characterized in that, The construction of the overall geometric model of the grinding system based on each structured grinding wheel model, the target machining object, and the machining environment includes: Obtain the computational domain that surrounds the grinding wheel and covers the grinding area of ​​the target workpiece; The computational domain, any structured grinding wheel model, and the reference model corresponding to the machining environment are assembled to obtain the overall geometric model of the grinding system.

4. The method according to claim 1, characterized in that, The step of meshing and setting physical parameters for the overall geometric model of the grinding system to convert it into a three-dimensional airflow field simulation model suitable for mathematical calculations includes: The overall geometric model of the grinding system is filled with multiple preset unstructured meshes of different densities, and the minimum grinding gap between the grinding wheel and the target workpiece in the overall geometric model of the grinding system is refined to obtain multiple refined overall geometric models corresponding to the multiple preset unstructured meshes. In the multiple encrypted overall geometric models, the rotating fluid domain and the surrounding fluid domain that rotate synchronously with the grinding wheel are obtained respectively; wherein, the surrounding fluid domain is used to characterize the spatial region occupied and flowed by fluid in the overall geometric model of the grinding system; Error and complexity calculations were performed on the rotation domain and surrounding fluid domain under different preset grids to obtain the calculation results corresponding to each preset grid. Among the preset grids, the optimal preset grid whose calculation results satisfy the preset conditions is selected; The optimal preset mesh and preset physical parameters are encapsulated to obtain the three-dimensional airflow field simulation model.

5. The method according to claim 1, characterized in that, The calculation of the air barrier weakening intensity of each group of trench configurations based on the three-dimensional airflow field simulation model includes: In the three-dimensional airflow field simulation model, based on the same grid density, the groove configurations of each group are compared and analyzed. The airflow field is calculated for each group of groove configurations in the three-dimensional airflow field simulation model to obtain the air barrier weakening strength of each group of groove configurations.

6. The method according to claim 5, characterized in that, The step of performing airflow field calculations on each group of trench configurations in the three-dimensional airflow field simulation model to obtain the air barrier weakening intensity of each group of trench configurations includes: Replace the current groove configuration in the three-dimensional airflow field simulation model with any groove configuration to obtain the replaced three-dimensional airflow field simulation model. In the replaced three-dimensional airflow field simulation model, calculate the absolute values ​​of the peak positive and negative pressures on the surface of the target processing object; The air barrier weakening intensity of each group of trench configurations is obtained by summing the absolute values ​​of the positive and negative pressure peaks.

7. The method according to claim 1, characterized in that, The grinding fluid nozzle model is added to the overall geometric model of the replaced grinding system, and mesh generation and physical parameter settings are performed to obtain a gas-liquid two-phase flow simulation model, including: A grinding fluid nozzle model is established at the tangential or normal position of the grinding wheel in the replaced overall geometric model of the grinding system to obtain the updated model; wherein, the grinding fluid nozzle model includes: nozzle orifice diameter and nozzle-to-workpiece distance parameters; The overlapping areas of the updated model are removed to form a deduplicated model that includes the grinding wheel, the target object being processed, the nozzle, and the fluid domain; The deduplicated model is meshed and its physical parameters are set to obtain a gas-liquid two-phase flow simulation model.

8. The method according to claim 1, characterized in that, In the gas-liquid two-phase flow simulation model, multiple sets of groove size parameters are set based on the candidate grinding wheel configuration, and simulation calculations are performed using a preset grinding fluid injection speed to obtain the effective flow rate of the grinding fluid, including: Input any set of groove size parameters and preset grinding fluid injection speed into the gas-liquid two-phase flow simulation model to obtain the distribution map of grinding fluid in the grinding zone, the distribution map of grinding fluid in the grinding zone, the mass flow rate of grinding fluid at the minimum grinding gap and the mass flow rate of nozzle inlet under any set of groove size parameters. The ratio between the mass flow rate of the grinding fluid at the minimum grinding gap and the mass flow rate at the nozzle inlet is determined as the effective flow rate of the grinding fluid. Correspondingly, in the gas-liquid two-phase flow simulation model, after setting multiple sets of groove size parameters based on the candidate grinding wheel configuration, and performing simulation calculations using a preset grinding fluid injection speed to obtain the effective flow rate of the grinding fluid, the method further includes: The cooling and lubrication performance of the candidate grinding wheel configuration is evaluated based on the ratio between the mass flow rate of the grinding fluid at the minimum grinding gap and the mass flow rate at the nozzle inlet, as well as the uniformity index of the grinding fluid in the grinding zone as characterized in the distribution map.

9. The method according to claim 3, characterized in that, The processing environment includes: a grinding wheel with a diameter of 400 mm and a width of 25 mm; a minimum grinding clearance between the grinding wheel and the target object being processed set to 0.1~1 mm; the target object being processed is located directly below the grinding wheel; and the size of the calculation domain is 500 mm × 450 mm × 25 mm.

10. A structured grinding wheel performance evaluation system for grinding optical components, characterized in that, The system includes: The model building module is used to construct a structured grinding wheel model with multiple groove configurations and an overall geometric model of the grinding system based on the target processing object and processing environment of fused silica optical element grinding. The model conversion module is used to perform mesh generation and physical parameter setting on the overall geometric model of the grinding system, so as to convert the overall geometric model of the grinding system into a three-dimensional airflow field simulation model that can be used for mathematical calculations. The configuration screening module is used to calculate the air barrier weakening strength of each group of groove configurations based on the three-dimensional airflow field simulation model, and to determine the groove configuration with the highest air barrier weakening strength as the candidate grinding wheel configuration. The configuration replacement module is used to update the grinding wheel configuration in the overall geometric model of the grinding system to the candidate grinding wheel configuration, so as to obtain the replaced overall geometric model of the grinding system; The parameter setting module is used to add a grinding fluid nozzle model to the overall geometric model of the replaced grinding system, and to perform mesh generation and physical parameter setting to obtain a gas-liquid two-phase flow simulation model. The simulation calculation module is used to set multiple sets of groove size parameters based on the candidate grinding wheel configuration in the gas-liquid two-phase flow simulation model, and to perform simulation calculations using a preset grinding fluid injection speed to obtain the effective flow rate of the grinding fluid. The parameter selection module is used to select the target trench parameter corresponding to the largest effective flow rate from the multiple sets of trench size parameters based on the effective flow rate. The performance verification module is used to verify the performance of a grinding wheel with the target groove parameters in an experimental platform using preset grinding process parameters.

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