螺杆挤出机挤出过程数值模拟研究进展

介绍了数值模拟方法的基础及其优点,综述了国内外单螺杆、双螺杆、多螺杆挤出机挤出过程数值模拟研究进展。     

不同类型锥形双螺杆挤出机熔体输送段的模拟分析

利用计算流体力学软件Poly Flow软件模拟分析了三种类型的锥形双螺杆挤出机的流场特性,通过对速度场、压力场和剪切应力场等挤出过程中的重要场量的后处理,分析了三种类型的锥形双螺杆挤出机的挤出性能。     

生物型降解母料的挤出特点分析

本文针对生物型降解母料的特点，结合在同向双螺杆挤出机挤出造粒过程中所出现的现象、从双螺杆挤出机的主机结构、配置、操作等方面进行了分析探讨，并介绍了我们在生物降解母料双螺杆挤出造粒方面的最新进展。     

自洁型非对称同向双螺杆挤出机混合分析

设计了自洁型非对称同向双螺杆,并采用实验研究及数值模拟方法分析其混合特性。采用活性纳米CaCO3（nano CaCO3）填充线形低密度聚乙烯(PE LLD)的体系进行实验研究,在挤出量一定的前提下分别在自洁型非对称同向双螺杆挤出机以及普通同向双螺杆挤出机上造粒,通过扫描电子显微镜观察产品中nano CaCO3分布情况。结果表明,非对称双螺杆挤出PE LLD/nano CaCO3复合材料中nano CaCO3分布较为均匀,粒径尺寸更小,具有明显的增韧效果,这与数值模拟结果一致。     

双螺杆挤出机及其应用

该书是作者在汇集了近年来国内外双螺杆挤出机理论研究成果和设计发展及作者本人十多年对双螺杆挤出过程研究成果的基础上写成的。本书是一本关于双螺杆挤出机及其应用的专著,详细介绍了双螺杆挤出过程理论,双螺杆挤出机设计和双螺杆挤出机的应用。适合大专院校相关专业的教师、本科生和研究生,双螺杆挤出机设计制造单位的技术人员和塑料改性研究单位及改性料生产厂家的技术人员应用。     

国家科学技术学术著作出版基金资助：双螺杆挤出机及其应用

耿孝正　编著该书是作者在汇集了近年来国内外双螺杆挤出机理论研究成果和设计发展及作者本人十多年对双螺杆挤出过程研究成果的基础上写成的。本书是一本关于双螺杆挤出机及其应用的专著 ,详细介绍了双螺杆挤出过程理论 ,双螺杆挤出机设计和双螺杆挤出机的应用。适合大专院校相关专业的教师、本科生和研究生 ,双螺杆挤出机设计制造单位的技术人员和塑料改性研究单位及改性料生产厂家的技术人员应用。本书内容共四篇十二章。第一篇 (第一、二章 ) ,介绍了聚合物加工的几个基本阶段 ,单螺杆挤出过程 ,双螺杆挤出机的分类 ,主要技术参数和双螺…     

国家科学技术学术著作出版基金资助 双螺杆挤出机及其应用

耿孝正　编著该书是作者在汇集了近年来国内外双螺杆挤出机理论研究成果和设计发展及作者本人十多年对双螺杆挤出过程研究成果的基础上写成的。本书是一本关于双螺杆挤出机及其应用的专著 ,详细介绍了双螺杆挤出过程理论 ,双螺杆挤出机设计和双螺杆挤出机的应用。适合大专院校相关专业的教师、本科生和研究生 ,双螺杆挤出机设计制造单位的技术人员和塑料改性研究单位及改性料生产厂家的技术人员应用。本书内容共四篇十二章。第一篇 (第一、二章 ) ,介绍了聚合物加工的几个基本阶段 ,单螺杆挤出过程 ,双螺杆挤出机的分类 ,主要技术参数和双螺…     

操作条件对双螺杆挤出机性能的影响及控制

分析了啮合型双螺杆挤出机挤出过程的基本特点 ,并在实验基础上探讨了操作条件对挤出机工作性能和挤出物的影响及其控制方法。     

超高分子量聚乙烯双螺杆挤出的研究

研究了双螺杆挤出机和鱼尾型模具挤出超高分子量聚乙烯的生产方法；讨论了超高分子量聚乙烯在螺杆中的输送过程、模具的设计原理和生产工艺。研究结果表明，采用双螺杆挤出机，既可以是平行同向双螺杆，也可以是锥型异向双螺杆挤出机，螺杆轴向耐压４０ＭＰａ以上，配以鱼尾型模具，模具压缩比为１．５～２．０，带有冷却装置，采用合适的挤出工艺，能实现超高分子量聚乙烯板材及异型材的连续生产。这一生产方法填补了国内空白     

塑料特种成型技术

第二讲 特种挤出成型一、双螺杆反应挤出 反应挤出技术是利用双螺杆挤出机完成单体、预聚物的反应合成过程及聚合物的接枝、嵌段、共聚、交联、最终挤出成为塑料制品的一种新颖挤出工艺。用作反应挤出的双螺杆挤出机既是传统意义上的混炼塑化成型设备,又是化学合成的反应器,在挤出过程中完     

Corotating Twin-Screw Extrusion Reactive Extrusion-Devolatilization Model and Software

The modular corotating twin-screw extruder is an increasingly widely used polymer processing machine. This paper describes analyses of reactive extrusion and devolatilization in a modular corotating twin-screw extruder. The results of the analyses are intergrated into a comprehensive model and computer software for the modular corotating twin-screw extrusion process.     

聚氯乙烯/木粉复合材料的研究进展

综述了近年来国内外聚氯乙烯（PVC）/木粉（WF）复合材料的研究进展,对新型的行星辊轮双螺杆挤出机、带有干燥器的锥形双螺杆挤出机以及能直接将木粉输送到挤出机中的"WoodTruderTM"挤出系统等新型设备和工艺进行了介绍,对PVC/WF复合材料中使用的润滑剂、冲击改性剂、增塑剂、相容剂等助剂的研究进展进行了总结,并对PVC/WF复合材料的微发泡工艺和环保性能进行了介绍和评述,在此基础上对PVC/WF复合材料的发展趋势进行了展望。     

基于ANSYS软件的双螺杆挤出机的计算机模拟与分析

介绍了应用ANSYS软件对常用的啮合型同向旋转双螺杆挤出机挤压加工过程进行计算机模拟分析的方法、过程和主要结论;同时介绍了其他常用流体软件对双螺杆挤出机模拟分析的应用情况。分析表明:用ANSYS软件可以对双螺杆挤出机的螺纹流道、捏合块进行压力场、速度场、流量及回流、剪切速率、剪应力和混合效果等计算机模拟分析分,析结果与实验结果基本一致。     

Modelling extrudate expansion in a twin-screw food extrusion cooking process through dimensional analysis methodology

A new phenomenological model is proposed to correlate extrudate expansion and extruder operation parameters in a twin-screw food extrusion cooking process. Buckingham's pi dimensional analysis method is applied to establish the model. Three dimensionless groups, i.e. pump efficiency, water content and temperature, are formed to model the extrusion process from dimensional analysis. The model is evaluated with experimental data for extrusion of whole wheat flour and fish feed. The average deviations of the model correlations are 5.9% and 9% based on experimental data for the whole wheat flour and fish feed extrusion, respectively. An alternative four-coefficient extrudate expansion equation is also suggested for the three dimensionless groups. The average deviations of the alternative equation are respectively 5.8% and 2.5% in correlation with the same set of experimental data.     

Resin distribution along axial and circumferential directions of self-wiping co-rotating parallel twin-screw extruder

A self-wiping co-rotating twin-screw extruder (TSE) is operated in a starved state in which the screws are partially filled with resin. Understanding the resin distribution on the screw surface of a TSE in this state is essential for the design, operation, and maintenance of the twin-screw extrusion process. Accordingly, in this study, the circumferential and axial distribution of resin in a TSE were simulated using a novel method combining the mathematical formulation of Hele–Shaw flow, the finite element method, and a newly developed down-wind pressure updating scheme. The results of the simulation were found to be in good agreement with experimental measurements. The proposed simulation method enables the detailed visualization of resin distribution in the entire axial and circumferential directions over the length of a TSE, improving the ability to determine both the devolatilization and fiber attrition during the extrusion process.     

Characteristic analysis on a reactive extrusion process for the imidization of poly(styrene-co-maleic anhydride) with aniline

The imidization of poly(styrene-co-maleic anhydride) (SMA) with aniline by reactive extrusion is investigated in a co-rotating twin-screw extruder. During this reactive extrusion, the process temperature is much higher than the boiling point of the aniline. Accordingly, most of the aniline should be vaporized immediately after being fed into the extruder, occupies the unfilled part of the extruder, and is transferred to the melt phase where it is consumed through the reaction. Based on the mechanism of this vapor-melt heterogeneous process and experimental data for residence time distribution (RTD) in the extruder, a continuous process model is developed. The effects of operating conditions including temperature, throughput, and screw rotation speed on the reaction kinetics are discussed by both experimental data and model simulation. The results indicate that the residence time and the mass transport of aniline from vapor to melt phase should play significant roles in this heterogeneous reactive extrusion process.     

Modeling melt conveying and power consumption of co-rotating twin-screw extruder kneading blocks: Part B. Prediction models

Intermeshing co-rotating twin-screw extruders are very versatile because their screw configurations can be tailored both to the application and to the properties of the materials used. Finding the best screw configuration is one of the main purposes of twin-screw extrusion modeling, and requires models that accurately predict conveying and power consumption. The better the process can be predicted, the better the requirements of the final product can be met. We present novel prediction models of the conveying and power-consumption behaviors of intermeshing co-rotating twin-screw extruder kneading blocks for Newtonian fluids. These are based on numerical simulations and therefore consider the complex three dimensional (3D) geometry of this element type without the need for common simplifications. Our models are thus capable of including all leakage flows and gap influences, which are usually ignored, for example, by the flat-plate model. Since our models are derived by symbolic regression based on genetic programming, they consist of algebraic functions and are low-threshold. They can be used to calculate various process parameters for individual kneading blocks or entire screw configurations, as illustrated by a use case.     

双螺杆挤出机的关键技术

叙述了双螺杆挤出机的技术关键点,以及当前国内外双螺杆挤出机厂家为提高生产效率和产品性能所做的技术创新,当前挤出设备的发展方向以节能、高效、环保为主,文中列举了几种新的技术改进趋势,以及新的应用工艺,以此和业界专家分享双螺杆挤出机行业的最新技术成果。     

塑料特种挤出装备研究现状和发展

结合特种挤出技术与装备的研究实践，对国内外特种挤出技术的研究现状和发展趋势进行了述评。重点介绍了最新研制成功的双螺杆挤出机。往复式销钉螺杆挤出机，串联式磨盘螺杆挤出机。微型高速低粘度单螺杆挤出机和熔体齿轮泵挤出机的结构特点和应用领域。并对今后研究方向提出了建议。     

新型偏心三螺杆挤出机流体混合特性分析

在传统的三螺杆挤出机的基础上,设计了一种新型偏心三螺杆挤出机。该三螺杆挤出机中具有螺杆几何结构偏心、螺槽构型呈梯度变化特殊以及较高的面积利用系数等特征。利用有限元法对聚丙烯（PP）熔体在新型偏心三螺杆挤出机中流动和混合规律进行三维数值模拟,给出偏心三螺杆挤出机中压力和速度分布规律,计算了3种偏心螺杆挤出流场的停留时间分布、分布指数、分离尺度、最大剪切应力等混合表征参数。结果表明,螺杆偏心距不仅决定了螺杆端面形状,也改变了螺槽梯度的变化程度。随着螺槽梯度的逐渐减小,挤出机内粒子团聚效应逐渐降低、物料剪切作用逐渐增强。在3种新型偏心三螺杆挤出机中,偏心距e=3 mm的新型偏心螺杆挤出机的混合性能相对较好。