Numerical Simulation And Field Synergy Analysis Of Heat Transfer Enhancement In Screw Plasticizing System

Plastic products are widely used in all aspects of production and life,playing an important role in today's society.The plastic products are different from the metal products.In the process of processing,the polymer materials have experienced the process of heating,melting and curing.The quality of the plasticized products and the efficiency of the heat transfer are two important indexes in the process of plastic processing.The traditional screw plasticizing system has not considered enhancing heat transfer by enhancing mass transfer in improving plasticized product quality and enhancing heat transfer efficiency.For this reason,based on the new idea of polymer melt calculus to strengthen convective heat transfer and high efficiency plasticization,a new type of screw which called field synergetic screw,and analysis of its field synergy,in order to improve the uniformity and heat transfer efficiency of plasticizing process.The application of field synergy theory is extended to the field of high viscosity non Newtonian fluid heat transfer enhancement.On the basis of the previous research results,this paper uses the field synergy theory and numerical calculation method to further analyze the heat transfer performance of the new type screw and the traditional screw structure during the plasticizing process,and optimize the structure of new type of enhanced heat transfer screw.The results obtained in this paper are as follows:(1)The mechanism of torsional components of field synergy screw is studied:The structure design principle of the new type of heat transfer element and the mechanism analysis of heat and mass transfer are analyzed,and it expounds various indicators which are used to evaluate the flow and heat transfer performance of the screw.Through the analysis of fluid streamline diagram,velocity vector graph,temperature distribution diagram,heat transfer performance and field synergy,it is concluded that the torsional components can enhance the radial convection flow and heat transfer,enhance the heat transfer performance and the synergism of the uniform temperature field and the velocity field.It is obvious to enhance the heat transfer performance and field synergy of the plasticizing process.(2)Enhanced heat transfer effect of field synergetic screw in plasticizing and metering section:By comparing the difference of flow heat transfer and field synergy between the common screw and field synergetic screw in the melting section and the metering section of the plasticizing system,it is found that the new type screw has obvious effect on the convective heat transfer in the radial direction,the melting process of the melting section and the reduction of the synergetic angle of the field during the plasticizing and melting process.And in the measuring section,there is a more uniform temperature distribution in the new screw flow channel,and the temperature variance of the fluid is smaller,and the synergistic angle of the temperature gradient and the velocity vector in the new screw flow field is smaller than the ordinary screw channel,which means that there has better field covariance and heat transfer effect.(3)Structural optimization of field synergetic screw:Based on the above conclusion,by putting the torsional components into the ordinary screw in the form of inserts,the field synergetic screws with different embedding positions and numbers are obtained.Then study the difference of heat transfer performance during each field synergetic screw in the plasticizing and melting process.At last,a field synergetic screw with the best position and quantity of the new screw embedded in the screw is obtained.