双转子连续混炼机固体物料输送过程研究

对双转子连续混炼机转子喂料段固体物料的输送过程进行了理论分析,提出了描述此过程的物理模型。运用该物理模型,得出了计算连续混炼机固体输送速率的公式,并由此提出双转子连续混炼机的产量与喂料量成正比以及与转子转速无关的结论。     

双转子连续混炼机中的混沌混合行为研究

双转子连续混炼机是一种具有优异分散与分布混合特性的连续混炼设备。本文运用混沌流动理论,对双转子连续混炼机混炼流场的混沌流动特性进行了分析研究,提出了采用以物料停留时间为基准的修正Lyapunov指数来描述混合过程中发生的拉伸应变,并借助于有限元计算,得出流场绝大部分区域的修正Lyapunov指数大于零,并发现混炼流场中存在非常有利于拉伸、折叠流动的涡旋流动,赋予了双转子连续混炼机优异的分散与分布混合特性。     

双转子连续混炼机的研究

双转子连续混炼机在我国是一种新型的混炼机械。文章介绍了双转子连续混炼机混炼元件的主要特征，并研究了其混炼原理。从分布混合和分散混合两方面对混炼过程做了分析。     

双辊式型板压出机简介

日本神户制钢所的双辊式型板压出机,可将密炼机间歇排出的混炼胶连续地成型为适于后面工序用的某种规格的胶片。过去,密炼机下面多设置开炼下片机,但随着轮胎行业混炼生产率的大幅度增加,特别是大型高速混炼机的采用,使得原有的双辊压片机相形见拙,且难于满足精炼的质     

基于能量等效的双转子连续混炼机混炼段相似放大研究探讨

根据双转子连续混炼机自身特性和等效平均停留时间、等价转子顶部剪切速率的原则,以能量等效为衡量混合效果的准则,提出双转子连续混炼机混炼段相似放大设计的流程及其理论模型。在该模型确定的转子转速和喂料速率下,利用Polyflow软件模拟了机筒内径分别为30 mm和100 mm的双转子连续混炼机混炼段和卸料段内的流场特征,以能量等效为指导准则,通过对流场特征和混合效果进行分析,对所提出的相似放大设计理论模型进行了验证。     

双转子连续混炼设备的进展

双转子连续混炼机由于具有稳定、高效和节能的特点,在聚合物材料加工领域得到了广泛的应用。首先综述了双转子连续混炼机的国内外研发历程,梳理了双转子连续混炼机系统结构设计、转子结构优化和加工机理等的研究进展,并系统地分析了转子的楔入角、转子的螺棱数和转子的相位角等重要转子结构参数对聚合物材料结构与性能的影响。另外,总结了双转子连续混炼机在高填充母料、超高分子量聚乙烯(UHMWPE)加工和回收橡胶等领域的应用进展。最后,概述了双转子连续混炼设备的发展趋势,需要深入研究其加工机理,并且,不断朝着大型化、专业化、绿色化和智能化方向发展。     

双转子连续混炼机最佳转子相位角确定

采用流体运动的基本方程，建立了双转子连续混炼机两根转子之间横向流动流量的计算模型，推导出了两根转子之间横向流动流量的计算公式，分析了该流量随相位角的变化规律，确定了能实现最大流量的相位角数值。     

新型高填充改性高分子材料混合工艺与设备项目通过鉴定

由江苏工业学院提出、江苏工业学院和华东理工大学完成的江苏高校高新技术产业发展项目——“新型高填充改性高分子材料混合工艺与设备”日前在江苏常州通过了江苏省教育厅主持的鉴定。该项目通过对双转子连续混炼机的混炼转子进行改进,发明了一种高填充高效连续混炼机转子,同时对其混合特性和双转子连续混炼机在     

国内自行开发双转子连续混炼造粒机组

国内自行开发双转子连续混炼造粒机组江苏石油化工学院谢林生双转子连续混炼机，是一种既能连续工作，又保持了密炼机优越的混合特性的新型橡塑混炼机械。该机器的外形很象双螺杆挤出机，而加料与出料方式则并不相同。与密炼机类似，该机器的混炼腔为两个相互贯通的、横截...     

ECM30双转子连续混炼机转子及嵌入块结构对分散混合性能的影响

计算比较了双转子连续混炼机不同转子结构和嵌入块时的轴向速度分布、剪切应力和混合指数的分布，得到了转子结构和嵌入块的嵌入深度对ECM30双转子连续混炼机分散混合性能的影响。转子螺棱交汇区的长度减小，其流场的剪切作用增强，拉伸作用减小；转子螺棱包角增加，转子的返混能力增加，剪切和拉伸作用减小。增加嵌入块的高度，返混能力增强，剪切作用增加，拉伸作用减小。     

相向／同向转子密炼机混合效率的数值模拟

本文分别建立了相向旋转和同向旋转转子密炼机混炼流场的物理模型、数学模型和有限元模型,并用计算流体动力学软件Fluent对三维等温流场进行了模拟。通过对模拟结果的后处理和对粒子轨迹的统计,对相向和同向旋转转子密炼机的分散混合和分布混合性能进行了对比研究和定量描述。     

Powder mixing in a horizontal batch mixer

The mixing process in a horizontal batch mixer with a twin spiral rotor has been investigated.A mixture of crushed wheat and sodium chloride was mixed in a model mixer. The concentration of sodium chloride in mixture samples was checked as a function of the mixing time and sampling place for various degrees of mixer filling. The sample composition was determined by conductometric determination of sodium chloride in water extracts of the sample. From the values obtained, the mixing degree was calculated as defined by the variation coefficient along the whole mixer, as a function of the mixing time.In analysing the data and empirical correlation between the concentration of component under study and the place and time of mixing, C/C? = f(x, t) was obtained and compared with industrial experiments using radionuclides as tracers.     

Correlation between processing conditions and fiber breakage during compounding of glass fiber‐reinforced polyamide

The inter‐relationship between processing conditions and fiber breakage has been studied for glass fiber‐reinforcedpolyamide 12, prepared using (i) an internal batch mixer, (ii) a laboratory scale corotating twin screw extruder, and (iii) an industrial scale twin screw extruder. The average fiber lengths and fiber length distributions were measured for various compounding conditions (screw or rotor speed, mixing time, feed rate). Experimental results have shown that fiber breakage depends on both screw speed and mixing time, the later being controlled, in an extruder, by the feed rate. For a given compounding system (batch mixer or twin screw extruder), the energy input (specific mechanical energy, SME) during the compounding process is found to be a reliable parameter, which governs fiber length (average, minimal, and maximal) evolution. Experimental data are correctly described with a model defining change in fiber length as a function of SME. POLYM. COMPOS., 2011. © 2011 Society of Plastics Engineers     

热熔挤出中吲哚美辛熔化和混合机理的研究

选用难溶性药物吲哚美辛（INM）为模型药物,泊洛沙姆188（F-68）为载体,从数值模拟和实验研究2方面研究采用双转子混合器制备F-68/INM固体分散体过程中,转子速比对INM熔化相变和混合过程的影响规律。结果表明,提高转子速比,INM在载体F-68中的分布、分散混合和熔化扩散作用均得到增强,INM的溶出进程加快。     

Influence of design on dispersive mixing performance in an axial discharge continuous mixer—LCMAX 40

The axial discharge continuous mixer combines the features of a continuous mixer and a twin screw extruder, expanding the flexibility of this compounding machine. In this work we analyzed the influence of rotor design on the dispersive mixing performance of a LCMAX 40 unit. Specifically we looked at various arrangements for the pushing and counter pushing units in the design of the LCMAX 40. A fluid dynamics analysis package—FIDAP, based on the finite element method, was used to model the flow behavior of a power law model fluid under different pressurization conditions. Dispersive mixing efficiency was quantified in terms of shear stresses and elongational flow components generated in the flow field. We found that the counter-pushing unit generally contributes more in building up high shear stresses. However, the generation of elongational flow components, which is beneficial for dispersive mixing, is not solely dependent upon the pushing–counter pushing configuration but rather on the overall rotor geometry. We found that the maximum number of counter-pushing units in the rotor design of the LCMAX 40 should not exceed two in order to provide adequate material pumping. Rotor designs with alternating arrangements of pushing and counter-pushing units provide overall better dispersive mixing conditions.     

Optimization of rotor speed based on stretching,efficiency, and viscous heating in nonintermeshing internal batch mixer: Simulation and experimental verification

Optimization of rotor speed based on stretching, efficiency, and viscous heating in nonintermeshing internal batch mixer has been investigated using polymer melt. A practical optimization technique was followed for optimization. Four different rotor speeds were used and characterized numerically with viscous dissipation and stretching. The heat distribution between rotor edge and mixer wall was calculated. Stretching experienced by the fluid was analyzed and the result was verified experimentally using particle tracking method. Exponential increase of energy dissipation between the rotor edge and the barrel at higher speed highlighted the importance of choosing the thermal properties of the polymer to avoid thermal degradation. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Nylon 6/ethylene propylene rubber (EPM) blends: Phase morphology development during processing and comparison with literature data

The morphology of immiscible blends of nylon 6 and ethylene propylene rubber blends (EPM) was studied. The blends were prepared by melt blending in a twin‐screw miniextruder and a Haake Rheocord mixer. The influence of the blend ratio, time of mixing, rotation speed of the rotors, mixing temperature, and quenching of the extruded melt at low temperature on the phase morphology of the blends was quantitatively analyzed. The morphology was examined by scanning electron microscopy (SEM) after preferential extraction of the minor phase. The SEM micrographs were quantitatively analyzed for domain‐size measurements. The morphology of the blends indicated that the EPM phase was preferentially dispersed as domains in the continuous nylon matrix up to 40 wt % of its concentration. A cocontinuous morphology was observed at 50 and 60 wt % EPM content followed by a phase inversion beyond 60 wt % of EPM where the nylon phase was dispersed as domains in the continuous EPM phase. The size, shape, and distribution of the domains were evaluated by image analysis as a function of the blend composition. The effect of the time of mixing on the phase morphology was studied up to 20 min for the 30/70 EPM/nylon blend. The most significant domain breakup was observed within the first 3 min of mixing followed by a leveling off up to 15 min. This may be associated with the equilibrium between the domain breakup and coalescence. The influence of rotor speed on the morphology was insignificant at a high rotor speed although a significant effect was observed by changing the rotor speed from 9 to 20 rpm. The influence of high‐temperature annealing, repeated cycles of extrusion, the molecular weight of the nylon matrix, and the nature of the mixer type (twin‐screw miniextruder versus Haake Rheocord mixer) on the morphology was also investigated in detail. The experimental results were compared with literature data. Finally, the extent of interface adhesion in these blends was analyzed by examination of the fracture‐surface morphology. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1405–1429, 1999     

啮合式转子密炼机中转子的模拟和设计

对聚合物在啮合式转子密炼机中的流动进行了模拟分析,并分析了4种不同类型啮合式转子的混炼作用,还将模拟分析结果与分离式转子密炼机的实验结果进行了比较,结果表明,啮合式转子密炼机的填充因数比分离式转子密炼机大。     

Internal mixing: A practical investigation of the influence of intermeshing rotor configuration and operating variables on mixing characteristics and flow dynamics

This paper deals with the measurement and interpretation of pressures and temperatures produced by the mixing of a rubber compound in the chamber of an internal mixer equipped with interlocking rotors. Pressure transducers and infrared/fiber optic temperature sensors were sited flush with the inner surface of the mixing chamber of a Francis Shaw KO Intermix of 2 L chamber volume. The variation of pressure with transducer position In the chamber wall and with rotor position was measured for selected fill factors and rotor speeds at “equilibrium” conditions (quasi-static power requirement for the mixer) and at intervals during a complete mixing cycle. Two rotor designs were studied. Interpretation of the results was carried out with reference to biconical rotor rheometer measurements on the mixed rubber compounds and by reference to four regimes of viscoelastic behavior identified for two-roll mill mixing. A basic flow analysis was carried out by use of the lubrication approximation in conjunction with an isothermal power-law model.     

Power consumption characteristics of an in‐line silverson high shear mixer

In‐line rotor stator mixers differ from in‐tank versions because the flow is often controlled independently of the rotor speed. For in‐tank devices the turbulent power can be adequately described by single impeller type power number. For an in‐line rotor‐stator mixer it is found that the power transmitted by the rotor consists of a power term and a flow term. The constants in this expression are normally obtained from a multilinear regression of a large matrix of experiments. Two simplified methods of obtaining these constants from limited data sets by (1) torque measurement and (2) by heat balance are described herein. These are used to determine the constants for a Silverson 150/250 MS inline mixer with different rotor stator arrangements from the laminar to turbulent regimes. The power and Metzner‐Otto constants determined are shown to be in good agreement to data for a larger matrix of experimental data. © 2011 American Institute of Chemical Engineers AIChE J, 58: 1683–1692, 2012