新型断开螺旋双轴搅拌机优化设计方法

优化设计方法以新型断开螺旋双轴搅拌机的主要技术参数及工作机理,结构设计等方面作为优化设计参数,并以实践条件来确定其约束条件,达到了预期目的;并对该机系列化设计提供了可靠的依据,具有较好的指导方法和应用价值。     

家用食品搅拌机的共生整合设计

目的为更好地满足家用食品搅拌机的用户需求,将基于共生整合设计理念及设计方法运用到家用食品搅拌机的设计中。方法在设计过程中,结合共生整合设计的概念、类别,分析并研究形态模块和功能模块整合设计方法,应用形态和功能的模糊评价过程,对其进行形态模块与功能模块划分及匹配合理性评价,选取最理想的评价值,对家用食品搅拌机进行整合设计。结果得出实现使用方式和功能多样化的设计方案,借助搅拌机机头模块的旋转、上升、下降动作,实现榨汁、研磨、搅拌功能,这些功能又被整合于机头模块,体现共生整合设计理念。结论通过形态模块和功能模块的整合设计方法,可以节约产品使用空间,简化产品造型,缩减操作程序,实现功能多样化和集约化。     

可调式跌水网格混合器性能研究

研究了可调式跌水网格混合器性能(水头损失、混合效率)与其主要设计参数(网格间距、网格与混合管的距离)的关系.结果表明:在网格与混合管距离为10 cm,网格间距为6 cm,单个网格面积为36 cm2的最优设计参数条件下,该混合器的混合效率可达到96%以上,水头损失为0.5 m左右;进水流量在50%范围内波动时,该混合器混合效率对流量变化不敏感,均可达到92%以上.     

Effects of rotor and stator geometry on dissolution process and power consumption in jet-flow high shear mixers

The jet-flow high shear mixer(JF-HSM)is a new type of intensified equipment with special configurations of the rotor and the stator.The mass transfer property and power consumption were studied in the solid-liquid system for a series of JF-HSMs involving different configuration parameters,such as rotor diameter,rotor blade inclination,rotor blade bending direction,stator diameter,and stator bottom opening diameter.The flow characteristics were examined by computational fluid dynamic simulations.Results indicate that the turbulent power consumption of the JF-HSM is affected by the change in rotor blade inclination and stator bottom opening.With the increase in the shear head size and the change in the rotor into a backward-curved blade,the solid-liquid mass transfer rate can be remarkably increased under the same input power.Dimensionless correlations for the mass transfer coefficient and power consumption were obtained to guide the scale-up design and selection of such a new type of equipment to intensify the overall mixing efficiency.     

Design and analysis of a millimeter‐wave injection locked frequency divider with transconductance boosting technique

This paper presents a degenerated injector (mixer) with transconductance boosted by biasing the mixer transistor in the knee region of its I‐V curve, without increasing the transistor size and its parasitics. This mixer can enhance the locking range of millimeter‐wave injection‐locked frequency dividers. To compensate the degradation of mixer transconductance (conversion‐gain) due to the degeneration effect, a neutralization technique is employed. Analyses are given for locking‐range and induced phase‐noise of the proposed divider for arbitrary injection strength. It is shown that the locking‐range, as a function of injection strength, is improved by increasing the fundamental component of transconductance. Using 180‐nm CMOS technology, a 1.78‐mW divider‐by‐two is designed with free‐running frequency of 27.92 GHz, locking‐range of 51 to 59.6 GHz, and figure‐of‐merit of 4.83 (GHz/mW). EM simulation results of the proposed and conventional structure are compared, which illustrates 56% improvement in locking‐range.     

依据马蹄变换的混沌流微混合器

为了实现微流控芯片对痕量试样的快速、均匀混合,依据"马蹄变换"数学模型,对流体进行"挤压拉伸"、"弯曲折叠"和"逆变换-交集"操作.基于此借助符号动力学系统计算出了"马蹄变换"后的李雅普诺夫指数,从理论上证明了,当满足"挤压"幅度0λ1/2且"拉伸"幅度μ2时,上述操作能够在低雷诺数的层流条件下,成功诱发混沌流.在此基础上,设计并制作了一款由4个"马蹄变换"混合单元组成,有效混合距离为13 mm的微混合器.利用COMSOL软件得到的数值仿真结果表明:当Re≥1时,流体的佩克莱数Pe≥10,此时微混合器诱发的混沌流将随着流速的加快而增强,并逐步成为促进混合的主要因素;当Re=10时,经4个混合单元后,试样的浓度方差σ=0.054,混合效果接近均匀.对微混合器芯片进行的可视化测试结果表明,荧光显微镜拍摄到的示踪剂颜色变化与仿真结果中的表面浓度云图一致;而不同pH试样的混合测试结果则证明了,基于"马蹄变换"数学模型设计的微混合器能够产生混沌流且实际效果理想.     

大高径比机械搅拌槽在湿法炼锌浸出工序的应用

介绍了某湿法炼锌厂常规浸出工艺中，空气搅拌槽能耗高，浸出条件难控制等问题，提出了由空气搅拌槽改造为大高径比机械搅拌槽的方案，确定了搅拌器的参数，改造后获得了较好的节能效果。     

氯乙烯合成混合系统安全联锁控制的研究

针对氯乙烯合成混合系统游离氯超标,造成混合器防爆膜爆裂,停车时间过长,环境污染等问题,对混合器过氯安全联锁进行研究,并在Deltav系统中搭建模型,编写程序,实现了混合器过氯安全联锁自动化控制,从而提高了生产装置的安全性和减轻了人员劳动强度。     

Modeling mixing dynamics in uncovered baffled and unbaffled stirred tanks

This paper presents results of measurements performed in uncovered baffled and unbaffled stirred tanks. The Laser Doppler Anemometry (LDA) set consists of a 300 mW argon-ion laser generating two pairs of blue and green beams. Additionally, three turbulence models are verified to simulate mixing dynamics in uncovered baffled and unbaffled stirred tanks. Simulations are performed using both the steady- and the transient-state approach. The unbaffled tank was modeled using both the single- and the multiphase approaches. The cited correlations of the central vortex depth are used to verify the multiphase calculations. In order to reduce the computational time, a simplified numerical model is proposed. It assumes a single-phase simulation without the central vortex. The flow fields below the central vortex level are compared between the single- and the multiphase approach. The simplified model can be used both to design and optimize the mixing process.