| Diamond circular saw blade is an efficient cutting tool,which is used widely in hard and brittle materials processing,such as stone,concrete,ceramics and so on.However,the transverse vibration of a circular saw blade in processing can affect machining accuracy of stone and bring severe noise pollution.According to the research status and existing problems of vibration and noise control technology of the diamond circular saw blade in sawing process,the mechanical,acoustics and other disciplines of knowledge were used to solve the problems,the noise and vibration in cutting process optimization design of the dynamic characteristics of the diamond saw blade.The creative contributions can be summarized as follows:1.The modal analysis model of a saw blade based on finite element method was established,and the results were also verified by modal test.The influence of the thickness,the clamp diameter ratio and the speed of the saw blade on the inherent characteristics of the circular saw blade was determined by finite element modal analysis.The model of regenerative chatter of the circular saw blade was also established.According to the model,the lateral regenerative chatter of the circular saw could be calculated,which provided a theoretical support for reasonable design of a circular saw blade.2.The dynamic simulation model of the diamond circular saw blade-stone sawing system was constructed by FEM,FEM-SPH fixed coupling method,FEM-SPH adaptive coupling method.According to the simulation results,the pros and cons of each algorithm were analyzed,the feasibility and application scope of each algorithm in sawing machining were determined.The stone removal process was divided into three stages:small scale fracturing stage,large scale fracturing stage and repeated large-scale fracturing stage.According to the distribution of the equivalent stress on the surface of the saw blade and in the stone,the most vulnerable area of the model was determined and the influence of different sawing parameters on sawing force was obtained.3.The multi-physical coupling model of a circular saw blade sawing system was constructed,which was verified to be true by simulation analysis and experiment.The complex load excitation,the surrounding flow and the complex acoustic boundary conditions were taken into account existing in the actual sawing process.The acoustic response of the sawing system in complex environment was calculated,and the noise level of the saw blade was estimated based on the boundary element technique.Then the characteristics of flow field around the rotating saw blade were achieved as well as the influence of fluid-structure interaction on sound pressure level of cutting noise and vibration area of the saw blade on cutting noise,distribution of sound field in sawing noise.The method was verified to be effective by the experimental noise measurement.4.The method of sequence response surface method and hybrid optimization algorithm was used to optimize the size of a saw blade in order to reduce the sawing noise.The effectiveness of the method was verified by sawing experiment,which was then used to optimize the conventional circular saw with a diameter of 350 mm and an optimal result was obtained.The influence of design variables on the acoustic,deformation and stress of the saw blade could be received based on statistical analysis.Then the optimized circular saw blade was made and the correctness of the optimization results was verified by experiments.5.The dynamic topological optimization model of a circular saw blade was established based on the hybrid cellular automata algorithm and verified to be correct by experiment.The saw blade vibration attenuation and noise reduction were set as the design goal and the specific position load force response,displacement response as the multiple constraints,based on above results,the optimal slotted form was obtained.The feasibility of the optimization method in saw blade with slots was then determinded by comparison with the conventional one,which provided a new idea and theoretical support for the dynamic topology optimization design of the low noise saw blade. |
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