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叶片风速仪 1

柴油机 1

涡流 1

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硅基集成电路；毫米波；超宽带；变压器；低噪声放大器；倍频器；分频器；混频器 1

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Micronization of curcumin with biodegradable polymer by supercritical anti-solvent using micro swirlmixer

Kimthet Chhouk, Wahyudiono, Hideki Kanda, Shin-Ichro Kawasaki, Motonobu Goto

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 184-193 doi: 10.1007/s11705-017-1678-3

摘要： Curcumin is a hydrophobic polyphenol compound exhibiting a wide range of biological activities such as anti-inflammatory, anti-bacterial, anti-fungal, anti-carcinogenic, anti-human immunodeficiency virus, and anti-microbial activity. In this work, a swirl mixer was employed to produce the micronized curcumin with polyvinylpyrrolidone (PVP) by the supercritical anti-solvent process to improve the bioavailability of curcumin. The effects of operating parameters such as curcumin/PVP ratio, feed concentration, temperature, pressure, and CO flow rate were investigated. The characterization and solubility of particles were determined by using scanning electron microscopy, Fourier Transform Infrared spectroscopy, and ultra-violet-visible spectroscopy. The result shows that the optimal condition for the production of curcumin/PVP particles is at curcumin/PVP ratio of 1:30, feed concentration of 5 mg·mL , temperature of 40 °C, pressure of 15 MPa, and CO flow rate of 15 mL·min . Moreover, the dissolution of curcumin/PVP particles is faster than that of raw curcumin.

关键词： micronization curcumin polyvinylpyrrolidone supercritical anti-solvent swirl mixer

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Influence of mass air flow ratio on gas-particle flow characteristics of a swirl burner in a 29 MW pulverized

Rong YAN, Zhichao CHEN, Shuo GUAN, Zhengqi LI

《能源前沿（英文）》 2021年第15卷第1期页码 68-77 doi: 10.1007/s11708-020-0697-9

摘要： In a gas/particle two-phase test facility, a three-component particle-dynamics anemometer was used to measure the characteristics of gas/particle two-phase flows in a 29 megawatt (MW) pulverized coal industrial boiler equipped with a new type of swirling pulverized coal burner. The distributions of three-dimensional gas/particle velocity, particle volume flux, and particle size distribution were measured under different working conditions. The mean axial velocity and the particle volume flux in the central region of the burner outlet were found to be negative. This indicated that a central recirculation zone was formed in the center of the burner. In the central recirculation zone, the absolute value of the mean axial velocity and the particle volume flux increased when the external secondary air volume increased. The size of the central reflux zone remained stable when the air volume ratio changed. Along the direction of the jet, the peak value formed by the tertiary air gradually moved toward the center of the burner. This tertiary air was mixed with the peak value formed by the air in the adiabatic combustion chamber after the cross-section of / = 0.7. Large particles were concentrated near the wall area, and the particle size in the recirculation zone was small.

关键词： industrial pulverized coal boiler swirl burner air/particle flow particle dynamic analyzer (PDA)

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Micromixing performance of the teethed high shear mixer under semi-batch operation

《化学科学与工程前沿（英文）》 2022年第16卷第4期页码 546-559 doi: 10.1007/s11705-021-2069-3

摘要： Semi-batch operated reaction processes are necessary for some competitive reaction systems to achieve a desirable process selectivity and productivity of fine chemical products. Herein the structural and operating parameters of the teethed high shear mixers were adjusted to study the micromixing performance in the semi-batch operated system, using the Villermaux/Dushman reaction system. The results indicate that the rising of the rotor speed and the number of rotor teeth, the decrease of the width of the shear gap and the radial distance between the feed position and the inner wall of stator can enhance the micromixing level and lead to the decrease of the segregation index. Additionally, computational fluid dynamics calculations were carried out to disclose the evolution of the flow pattern and turbulent energy dissipation rate of the semi-batch operated high shear mixer. Furthermore, the correlation was established with a mean relative error of 8.05% and R² of 0.955 to fit the segregation index and the parameters studied in this work, which can provide valuable guidance on the design and optimization of the semi-batch operated high shear mixers in practical applications.

关键词： high shear mixer semi-batch operation micromixing performance Villermaux/Dushman system segregation index

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Control of peak pressures of an HCCI engine under varying swirl and operating parameters

T. KARTHIKEYA SHARMA,G. AMBA PRASAD RAO,K. MADHU MURTHY

《能源前沿（英文）》 2016年第10卷第3期页码 337-346 doi: 10.1007/s11708-016-0401-2

摘要： The major advantages of homogeneous charge compression ignition (HCCI) are high efficiency in combination with low NO -emissions. However, one of the major challenges with HCCI is the control of higher peak pressures which may damage the engine, limiting the HCCI engine life period. In this paper, an attempt is made to analyze computationally the effect of induction swirl in controlling the peak pressures of an HCCI engine under various operating parameters. A single cylinder 1.6 L reentrant piston bowl diesel engine is chosen. For computational analysis, the ECFM-3Z model of STAR –CD is considered because it is suitable for analyzing the combustion processes in SI and CI engines. As an HCCI engine is a hybrid version of SI and CI engines, the ECFM-3Z model with necessary modifications is used to analyze the peak pressures inside the combustion chamber. The ECFM-3Z model for HCCI mode of combustion is validated with the existing literature to make sure that the results obtained are accurate. Numerical experiments are performed to study the effect of varying properties like speed of the engine, piston bowl geometry, exhaust gas recirculation (EGR) and equivalence ratio under different swirl ratios in controlling the peak pressures inside the combustion chamber. The results show that the swirl ratio has a considerable impact on controlling the peak pressures of HCCI engine. A reduction in peak pressures are observed with a swirl ratio of 4 because of reduced in cylinder temperatures. The combined effect of four operating parameters, i.e., the speed of the engine, piston bowl geometry, EGR, and equivalence ratio with swirl ratios suggest that lower intake temperatures, reentrant piston bowl, higher engine speeds and higher swirl ratios are favorable in controlling the peak pressures.

关键词： HCCI engine ECFM-3Z Swirl ratio peak pressures engine speed piston bowl geometry

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柴油机进气涡流自动试验系统设计与评价方法

于吉超,刘德新,冯洪庆

《中国工程科学》 2007年第9卷第5期页码 85-90

摘要：

涡流是影响柴油机经济性与排放特性的关键参数，在柴油机设计与改进过程一般通过气道稳态试验台进行测量与评价。介绍了一种自动化程度较高的气道稳态试验台的设计方案，可以自动控制气门升程和试验压力，适用于生产线。论述和比较了当前常用的测量与分析方法，并在试验台上进行了相应试验研究。结果表明，即使在相同试验条件下，不同测量方法或分析方法也会有不同的结果，在对不同试验台测量结果进行比较时，需要注意由于方法不同所引起的差异。

关键词：涡流柴油机叶片风速仪涡流动量计稳态试验台

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Spray characteristics of high-pressure swirl injector fueled with alcohol

WANG Xibin, CHEN Wansheng, GAO Jian, JIANG Deming, HUANG Zuohua

《能源前沿（英文）》 2007年第1卷第1期页码 105-112 doi: 10.1007/s11708-007-0012-z

摘要： The spray characteristics of methanol and ethanol with high-pressure swirl injector were explored experimentally and numerically. Experimental results show that the spray characteristics of methanol and ethanol had displayed the same trends as that of gasoline. Under the low back-pressure ambient conditions, the spray behavior exhibited a hollow cone with wide spray angle and initial spray slug at the tip, while the spray presented a solid cone in the case of high back-pressure. Vortexes in the opposite direction existed in the rear part of the spray under low back-pressure ambient conditions while the vortexes formed in the middle part under high back-pressure ambient conditions. Experiments also showed that methanol had the largest cone angle, while ethanol and gasoline presented almost the same cone angle. Simulation results indicated that methanol and ethanol had a slightly larger Sauter mean diameter (SMD) than that of gasoline with swirl injector. The SMD profile of methanol coincided well with that of ethanol under low back-pressure ambient conditions, but displayed a slightly larger value under high back-pressure due to fuel evaporation. Numerical simulation could successfully demonstrate the spray characteristics of high-pressure swirl injector for methanol and ethanol fuels.

关键词： low back-pressure diameter initial spray hollow middle

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Erratum to: Folded down-conversion mixer for a 60 GHz receiver architecture in 65-nm CMOS technology

Najam Muhammad AMIN,Zhi-gong WANG,Zhi-qun LI

《信息与电子工程前沿（英文）》 2015年第16卷第5期 doi: 10.1631/FITEE.14e0087

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Entropy production analysis of swirling diffusion combustion processes

Deodat MAKHANLALL, Linhua LIU,

《能源前沿（英文）》 2010年第4卷第3期页码 326-332 doi: 10.1007/s11708-009-0058-1

摘要： A critical factor in the design of combustion systems for optimum fuel economy and emission performance lies in adequately predicting thermodynamic irreversibilities associated with transport and chemical processes. The objective of this study is to map these irreversibilities in terms of entropy production for methane combustion. The numerical solution of the combustion process is conducted with the help of a Fluent 6.1.22 computer code, and the volumetric entropy production rate due to chemical reaction, viscous dissipation, and mass and heat transfer are calculated as post-processed quantities with the computed data of the reaction rates, fluid velocity, temperature and radiative intensity. This paper shows that radiative heat transfer, which is an important source of entropy production, cannot be omitted for combustion systems. The study is extended by conducting a parametric investigation to include the effects of wall emissivity, optical thickness, swirl number, and Boltzmann number on entropy production. Global entropy production rates decrease with the increase in swirl velocity, wall emissivity and optical thickness. Introducing swirling air into the combustion system and operations with the appropriate Boltzmann number reduces the irreversibility affected regions and improves energy utilization efficiency.

关键词： entropy-based design radiation transfer swirl magnussen combustion-model

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Combined static mixers for high viscous fluids mixing

Zhenhao XI, Weizhen SUN, Ling ZHAO, Zhaoyan LIU

《化学科学与工程前沿（英文）》 2009年第3卷第1期页码 93-96 doi: 10.1007/s11705-009-0112-x

摘要： A new static mixer Cross-over-Disc has been invented to strip off the boundary layer and to make strong radial mixing. The pressure drop of Cross-over-Disc is 12—26 times as large as that of empty pipe with equivalent diameter and length. The mixing performance of Cross-over-Disc with 14 elements has been investigated in the viscosity range of 190—250 Pa?s by decoloration method, and the gray analysis of images shows that mixing inhomogeneity is about 7.5% and 9.4% for the mixing ratio of 5∶1 and 10∶1, respectively. Furthermore, mixing inhomogeneity for a combination of static mixing elements (four from Cross-over-Disc and three pairs from Sulzer-type) can be decreased to 2.1%—3.1% within a reasonable range of pressure drop.

关键词： static mixer Cross-over-Disc pressure drop mixing performance high viscous fluid

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

Lin Yang, Wenpeng Li, Junheng Guo, Wei Li, Baoguo Wang, Minqing Zhang, Jinli Zhang

《化学科学与工程前沿（英文）》 2021年第15卷第2期页码 384-398 doi: 10.1007/s11705-020-1928-7

摘要： 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.

关键词： jet-flow high shear mixer solid particle dissolution power consumption characteristics CFD Simulation

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基于变压器CMOS超宽带毫米波电路分析与设计综述 Review Articles

Yi-ming YU, Kai KANG

《信息与电子工程前沿（英文）》 2020年第21卷第1期页码 97-115 doi: 10.1631/FITEE.1900491

摘要：近年来，由于大量毫米波无线应用的产生，具有更强通用性的宽带毫米波电路和系统引起广泛关注。总结了4种基于片上变压器结构超宽带毫米波电路的理论分析、设计方法和综合性能。其一为毫米波低噪声放大器，采用基于变压器的跨导增强和极点调谐技术；通过采用这两种技术，该电路同时实现了较大工作带宽、低噪声系数和良好功率增益。其二为毫米波注入锁定三倍频器，采用注入电流增强技术，有效拓展了倍频器的锁定带宽。进一步，采用类似注入锁定技术结合变压器高阶谐振腔方案，实现了一款超宽带毫米波注入锁定分频器。最后，介绍了一款E波段上混频器，其采用两路跨导并联结构和基于变压器的多极点负载，实现了优异线性度和较大工作带宽。

关键词：硅基集成电路；毫米波；超宽带；变压器；低噪声放大器；倍频器；分频器；混频器

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标题作者时间类型操作

Micronization of curcumin with biodegradable polymer by supercritical anti-solvent using micro swirlmixer

Kimthet Chhouk, Wahyudiono, Hideki Kanda, Shin-Ichro Kawasaki, Motonobu Goto

期刊论文

Influence of mass air flow ratio on gas-particle flow characteristics of a swirl burner in a 29 MW pulverized

Rong YAN, Zhichao CHEN, Shuo GUAN, Zhengqi LI

期刊论文

Micromixing performance of the teethed high shear mixer under semi-batch operation

期刊论文

Control of peak pressures of an HCCI engine under varying swirl and operating parameters