Finite Element Analysis Of The Flow Field Of A S-Shaped Rotor Farrel Continuous Mixer

Nowadays the trend of rubber and plastic industry is to be massive,automatic, continuous and intensive. In order to meet the requirement ofnew products and manufacture, extruders are expected to be more efficientin melting, generate higher mixing quality and output quantity with lessenergy consumed. But the traditional twin-screw extruders are not providedwith these properties, so improvement is necessary. The improvement anddevelopment of unconventional screw has been the focus. RGS, LGS byW.P. and FAMME, FCM, LCM by Farrel are some of the most famousmixing elements. As a new type of mixer, LCM not only maintains excellentcompounding properties of internal mixer, but also can productcontinuously. It has some merits such as many controllable variables, goodadaptability and faster rotating speed so it is applied widely in plastic andrubber mixing and pelletizing. Rotor is the core part of this kind of machine III北 京 化 工 大 学 硕 士 学 位 论 文that is composed of several screw sections with different angle anddirection. Because of rotors' complex geometry configure the flow patternunder the action of rotors is greatly complicate. In this paper, the simulation of the flow field of LCM is presented, andunder different operating conditions, the analysis of velocity and pressuredistribution is obtained. According to the results of velocity distributionanalysis, there are backward flows happening on rotor pushing surface andbetween barrel and screw flight, which is propitious to form a moreturbulent state and in favor of improvement of mixing quality. Results ofpressure analysis present that in high-pressure areas, because of the pushand press of rotors, material get melting and dispersed; though tiny gapbetween barrel and screw flight, material is forced into low-pressure areasbecause of the pressure difference, forming a circular flow pattern. Also thenet flow and axial pressure distribution are presented under differentoperating conditions and material properties. In our lab mixing experiments with PP/ nano-CaCO3 have be done.Electron microscope photos presented that when content is 10% and 20%,the dispersive effect is good, particle diameter less than 100nm.