Research Of Polymer Melt Volume Transportation Dynamic Model And The Analytical Solution

Traditional polymer processing equipment with a symbol of screw exist the problems oflong thermal history and high consumption, the vane extruder based on elongation rheology isa completely new theory and machinery for polymer processing. At present, the research ofthe single-screw melt conveying has been formed a relatively complete theoretical system, thework ways and plasticizing and conveying mechanism of the vane extruder are fully differentwith the screw extruder, thus, the screw melt conveying is not suitable for the vane conveyingprocess. The researches on the vane melt conveying are benefit for the optimization design ofthe vane extruder and have important scientific and practical significance to the developmentand improvement of the polymer processing theory based on elongation rheology.Vane plasticizing and conveying unite (VPCU) is the basic unit in polymer processingmachine, in this paper, the whole melt conveying process is studied systematically for the firsttime and the theory of melt volume conveying has been presented. Based on the vaneplasticizing and convey theory, melt conveying mathematical model and the energyconsumption model are developed to study the melt radical velocity, the circumferentialvelocity and the axial velocity in the VPCU, the experiment results are consistent with thepredictions of energy consumption models.The radical, the circumferential and the axial strain rate of the polymer have been studiedby the melt conveying mathematical model, the results shows that, the cavity volume ofperiodic change has important influences on the melt conveying and the polymer melt endureelongation strain both in the axial and the circumferential direction in the chamber, and anormal stress field in the axial direction formed in the chamber can help to convey the meltwith positive displacement and not depending on the properties of the materials.Through building the energy consumption model in the melt conveying process, theenergy consumption characteristic is analyzed in the paper. The research shows that, thehigher the temperature, the smaller energy consumption of polymer melt conveying is; energyconsumption in the polymer melt conveying press is proportional to the rotational speed of therotor; energy consumption in the polymer melt conveying press is inversely proportional tothe rotational speed of the rotor.Finally, energy consumption characteristics in polymer solids conveying process, meltconveying process and the whole plasticizing and conveying process including solidsconveying, melting and melt conveying in vane extrusion system have been studied experimentally by means of the compositional vane experimental device and the vaneextruder. The experiment results are consistent with the predictions of energy consumptionmodels.The method and equipment of polymer plasticizing and conveying based on elongationrheology is a completely new theory and machinery for polymer processing. The proposedmodels of polymer melt conveying process in VPCU and the energy consumption in theprocess laid a good foundation for further study of polymer vane plasticizing extrusionprocess and its mechanism. This study provided an important theoretical basis for thepromotion of the vane plasticization equipment for polymer processing.