摘要
[目的]为木塑型材生产提供合理的工艺控制参数,提升木塑挤出型材的质量。[方法]针对木塑挤出成型工艺控制问题,从木塑熔融体到挤出成型的工艺特性角度进行了分析研究,重点得出了模具域熔融体流场(温度分布、压力分布)与剪切率(流速)的关系特性及工艺阀值特征。通过建立单螺杆挤出机计量段和法兰处三维计算模型,对木塑挤出成型的若干典型工况流场进行了数值仿真。[结果]在一定的工艺阀值条件下,加热段的温度扰动对熔融体流场影响不大,而螺杆转速对流场影响较大,随着螺杆转速的增大,计量段压力逐渐减小,剪切率线性增大,粘度减小。[结论]验证了该文分析结论的正确性和一致性,根据分析结果得到较理想的木塑挤出工艺控制参数。
[ Objective ] The paper was in order to achieve better controlling parameters of extruder, so as to improve the guality of wood plastic ex- trusion profiles. [ Method] Focusing on process control of WPC extrusion,this paper studyed from the angle of WPC melt and process characteris- tics of extrusion molding, to get distribution curve and process threshold value of mould segment in flow field ( temperature field, pressure field) of melt and screw speed (velocity). numerical simulation on flow field of some typical working conditions of WPC extrusion, by constructing three-di- mensioal computational modelling of the metering section and flange of single screw extruder. [ Result ] Experimental results show that heating tem- perature little influences flow field while revolving speed greatly influences flow field with screw speed increases,pressure of metering section de- creases,shear rate increases and viscosity decreases, under the condition of process threshold. [ Conclusion ] Result verifies the correctness and consistency of the conclusion,according to results of analysis,better controlling parameters of extruder are achieved.
出处
《安徽农业科学》
CAS
2014年第3期823-827,共5页
Journal of Anhui Agricultural Sciences
基金
林业公益性行业科研专项(201204802)
关键词
木塑挤出机
熔融体流场分析
数值仿真
Extruder of wood and plastic
Flow field analysis of melt
Numerical simulation