| At present,the mixer is still the most widely used batch mixing equipment in the rubber industry.With the continuous development of the rubber and other polymer processing industries,the mixing performance requirements of the internal mixer are getting higher and higher.Synchronous rotor internal mixers are developed under this background,which has high production efficiency and good uniformity of rubber mixing,and is often used for processing rubber products with high uniformity.The rubber mixing process is very complicated,and the final properties of rubber products are also affected by multiple factors,such as process conditions,human factors and rotor configuration.As the core component of the mixer,the rotor has a great influence on the mixing effect of the mixer.At present,there are many researches on the rotor structure design,but most of these reaseach are still in the experience design stage.Therefore,it is extremely important to optimize the synchronous rotor.The specific work and research results completed in this paper are as follows:1.On the basis of extensive literature review,the first part of the thesis mainly introduces the mixing characteristics,development history,rotor configuration and the progress of numerical simulation and rotor optimization at domestic and foreign.Aiming at the problem that the current rotor design is too dependent on experience,a method of optimizing the rotor by using the optimization algorithm combined with numerical simulation technology is proposed in the paper.2.The parametric design program of synchronous rotor is programmed by MATLAB software,and the parametric design geometric model of synchronous rotor is established by CREO software.The corresponding mathematical solution model and material constitutive model are determined for the numerical simulation process,and assumereasonable boundary conditions;the finite element mesh model of synchronous rotor internal mixer is established by MST grid overlap technology,and the overall idea of simulation and optimization process is introduced.3.Based on the existing mixing theory of synchronous rotor mixer,the synchronous rotor mechanics model is constructed and its mixing characteristics are studied.The influence of rotor tip clearance and width,wedge angle,rib angle and length,and phase angle on mixing is analyzed clearly in the paper.4.The whole set of PSO algorithm optimization program is written.The global distribution index is used as the fitness function to optimize the synchronous rotor configuration.Compared with the optimization,the length of the long rib is reduced by8 mm,the length of the short rib is increased by 8mm,and the long-edge spiral angle is reduced by 1°,the short-edge spiral angle is increased by 12°;four gray correlation calculation programs are written by MATLAB,and the correlation analysis between the rotor rib structure parameters and the hybrid performance evaluation index is carried out.The results show that the effect of long and short rib helix angle on mixing is significantly greater than that of long and short rib ratios.The short-edge spiral angle has a great influence on the dispersion mixing and distribution mixing.The gray correlation evaluation method combined with the subjective weighting method and the entropy weight method are used to comprehensively evaluate the rotors in each group.The rotor structure with the best mixing effect is obtained,and the rotor structural parameters are consistent with the PSO optimized rotor structural parameters.5.Geometric model analysis,flow field cloud image comparison,numerical analysis comparison and necessary experimental comparison studies are carried out on the rotor before and after optimization.The results of comparative analysis show that the optimized synchronous rotor has better distribution and mixing effect than before,and its dispersion effect is superior to the optimized pre-synchronous rotor,indicating that the optimization process is feasible and the reliability of the optimization result.It provides a new idea for rotor design and development,it also has certain guiding significance for the development of mixing technology. |
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