机筒温度和螺杆转速对木塑挤出温度场影响的模拟分析

Simulation Analysis of the Influence of Barrel Temperature and Screw Speed on the Temperature Field of Wood-Plastic Extrusion

建立了木塑挤出加工过程流场的准三维模型,考虑相变潜热和黏性耗散热的影响,利用FLUENT软件分别对模型（在改变机筒加热温度和螺杆转速的条件下）进行了稳态传热模拟。通过分析模型的温度和液态分数分布情况,得到了木塑材料在挤出加工过程中的熔融变化规律,确定了机筒温度和螺杆转速对木塑挤出过程的影响。研究结果表明,木塑挤出过程中最适宜的机筒温度为使物料完全熔融的最低温度;机筒温度不变时,螺杆转速增加会使物料熔融效果变差,通过提高机筒的加热温度可以得到较好的效果。

A quasi 3 D-dimensional flow field model of wood-plastic extrusion process was established. Considering the influence of latent heat and viscous dissipation, steady-state heat transfer simulation was carried out by using the FLUENT software under the conditions of changing the barrel heating temperature and screw speed. By analyzing the distribution of temperature and liquid fraction in the model, the melting law of wood-plastic material in the process of extrusion process was obtained, and the influence of barrel temperature and screw speed on the extrusion process was determined. The results show that ： the most suitable barrel temperature for wood plastic extrusion is the minimum temperature to completely melt the material. When the barrel temperature is constant, the melting effect of the material becomes worse with the screw speed increasing, and the better effect can be obtained by increasing the heating temperature of the barrel.