Study Of Flow Field In Hot Cutting Pelletizing Die

With the rapidly growing national economy, the demand of plastic product is constantly increasing. Plastic pelleting is the important preparation for production of various plastic products, in the production line of extrusion pelleting, pelleting die is one of the most important parts. Generally, the design of flow channel was based on experience, so the decision often has a fault of blindness. Trial run and die repair would cost more time and resources, which cause the waste of human, material and financial resource. Therefore, the finite element simulating calculation of the flow field for pelleting flow channel was of great significance.In this study, the mathematical, physical and finite element models of hot cutting pelleting die which has the20million tons processing of PP every year were built. By using the CFD software, POLYFLOW, based on the three-dimensional isothermal FEM, the flow field in pelleting die was simulated and analyzed, and the profiles of pressure, velocity and viscosity were obtained.In order to study on the influence of main geometric parameters on the flow channel characteristics in the hot cutting pelleting die, the mathematical, physical and finite element models in which one of the geometric parameters was changed were rebuilt and analyzed. Based on simulation, analysis and research, the geometry parameters such as the distribution mode for the pre-distribution section, the length of the pre-distribution section and the molding section were optimized.In addition, the influence of the operating parameter and the material parameters on the pressure, velocity, viscosity field was analyzed and discussed.Generally, with the simulation and the analysis by the professional post-processor software FIELDVIEW and EXCEL which has the powerful functions of data analysis and drawing, some conclusions which have guiding significance on production practice were drawn.