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The Simulation and Experimental Validation on Gas-Solid Two Phase Flow in the Riser of a Dense Fluidized Bed

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Journal of Thermal Science 2009年第2期18卷 137-141页

作者： Xue-yao wang Fan jiang xiang Xu Sheng-dian wang Bao-guo Fan Yun-han Xiao Key Laboratory of Advanced Energy and Power, Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing 100190 Key Laboratory of Advanced Energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing China

Gas-solid flow in dense CFB (circulating fluidized bed)) riser under the operating condition, superficial gas 15.5m/s and solid flux 140 kg/m2s using Geldart B particles (sand) was investigated by experiments and CFD (computationalfluid dynamics) simulation. The overall and local flow characteristics are determined using the axialpressure profiles and solid concentration profiles. The cold experimental results indicate that the axial solid concentration distribution contains a dilute region towards the up-middle zone and a dense region near the bottomand the top exit zones. The typical core-annulus structure and the back-mixing phenomenon near the wall of theriser can be observed. In addition, owing to the key role of the drag force of gas-solid phase, a revised drag forcecoefficient, based on the EMMS (energy-minimization multi-scale) model which can depict the heterogeneouscharacter of gas-solid two phase flow, was proposed and coupled into the CFD control equations. In order to findan appropriate drag force model for the simulation of dense CFB riser, not only the revised drag force model butsome other kinds of drag force model were used in the CFD. The flow structure, solid concentration, clustersphenomenon, fluctuation of two phases and axial pressure drop were analyzed. By comparing the experimentwith the simulation, the results predicted by the EMMS drag model showed a better agreement with the experimentalaxial average pressure drop and apparent solid volume fraction, which proves that the revised drag forcebased on the EMMS model is an appropriate model for the dense CFB simulation.

关键词： riser gas-solid flow drag force EMMS model

Effect of Tbxl knock-down on cardiac performance in zebrafish

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Chinese Medical Journal 2010年第9期123卷 1182-1189页

作者： ZHANG Li-feng GUI Yong-hao wang Yue-xiang jiang Qiu SONG Hou-yan Children's Hospital Fudan UniversityShanghai 200032China Department of PediatricsShanghai Medical College of Fudan UniversityShanghai 200032China

Background Tbxl is the major candidate gene for DiGeorge syndrome （DGS）. Similar to defects observed in DGS patients, the structures disrupted in Tbxl-/- animal models are derived from the neural crest cells during development. Although the morphological phenotypes of some Tbxl knock-down animal models have been well described, analysis of the cardiac performance is limited. Therefore, myocardial performance was explored in Tbxl morpholino injected zebrafish embryos. Methods To elucidate these issues, Tbxl specific morpholino was used to reduce the function of Tbxl in zebrafish. The differentiation of the myocardial cells was observed using whole mount in situ hybridization. Heart rates were observed and recorded under the microscope from 24 to 72 hours post fertilization （hpf）. The cardiac performance was analyzed by measuring ventricular shortening fraction and atrial shortening *** Tbxl morpholino injected embryos were characterized by defects in the pharyngeal arches, otic vesicle, aortic arches and thymus. In addition, Tbxl knock down reduced the amount of pharyngeal neural crest cells in zebrafish. Abnormal cardiac morphology was visible in nearly 20% of the Tbxl morpholino injected embryos. The hearts in these embryos did not loop or loop incompletely. Importantly, cardiac performance and heart rate were reduced in Tbxl morpholino injected *** Tbxl might play an essential role in the development of pharyngeal neural crest cells in zebrafish. Cardiac performance is impaired by Tbxl knock down in zebrafish.

关键词： Tbxl zebrafish pharyngeal arches neural crest cells morpholino cardiac performance

基于小波能量谱和粗糙集的离心式压缩机振动故障诊断

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中南大学学报（自然科学版） 2009年第3期40卷 706-710页

作者：曾庆生王湘江南华大学机械工程学院湖南衡阳421001

结合小波能量谱和粗糙集理论各自优点,采用尺度小波能量谱计算公式对实测的时域信号进行尺度小波能量谱计算。以尺度小波能量谱为特征参数,对应故障为决策属性,结合粗糙集理论进行故障诊断规则获取,从而提出一种基于小波能量谱和粗糙集... 详细信息

结合小波能量谱和粗糙集理论各自优点,采用尺度小波能量谱计算公式对实测的时域信号进行尺度小波能量谱计算。以尺度小波能量谱为特征参数,对应故障为决策属性,结合粗糙集理论进行故障诊断规则获取,从而提出一种基于小波能量谱和粗糙集理论的离心式压缩机振动故障诊断方法。研究结果表明:测试样本对象诊断正确率为100%;该方法不需要精确计算离心式压缩机振动的故障特征频率,与传统的提取时域和频域参数方法相比,诊断正确率达88.5%。

关键词：小波能量谱粗糙集特征参数离心式压缩机故障诊断

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai wang Shao-jiang wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

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迟滞非线性系统自适应鲁棒控制

系统仿真学报 2010年第6期22卷 1502-1507页

作者：王湘江王兴松南华大学机械工程学院衡阳421001 东南大学机械工程学院.南京211189

介绍用超磁致伸缩材料与压曲放大机构组合设计的微位移驱动器,并设计了控制系统。建立了超磁致伸缩执行器基于输入电压-输出位移的机电系统传递函数模型。对微位移驱动器的迟滞特性用微分方程建立了模型。在此基础上构造迟滞模型与传递... 详细信息

介绍用超磁致伸缩材料与压曲放大机构组合设计的微位移驱动器,并设计了控制系统。建立了超磁致伸缩执行器基于输入电压-输出位移的机电系统传递函数模型。对微位移驱动器的迟滞特性用微分方程建立了模型。在此基础上构造迟滞模型与传递函数相结合的系统模型。由滑模控制理论,对所建模型提出了可以调节信号跟踪精度的自适应鲁棒控制方法,用Lyapunov稳定性理论进行了系统稳定性证明。通过系统模型仿真与simulink中的半实物仿真实现了该控制率,并验证了模型的准确性和补偿控制的有效性。

关键词：超磁致迟滞建模仿真自适应鲁棒控制

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自动装卸粮食散运车改装设计

起重运输机械 2006年第10期 16-19页

作者：王湘江南华大学机械工程学院

通过对标准东风运输车进行改装设计,使其成为可自动装卸散装粮食的专用粮食运输车,以达到降低粮食运输成本、提高效率的目的。

关键词：运输车改装设计鼓风机密封

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转子式机油泵多学科优化设计

内燃机工程 2009年第5期30卷 73-77页

作者：曾庆生杨毅王湘江南华大学机械工程学院衡阳421001

为了确保发动机转子式机油泵整体性能提高,以转子式机油泵泵油性能、质量以及抗冲击性能为目标函数建立了多学科设计优化模型,并充分考虑了各学科之间的耦合效应,采用自适应混沌优化算法对多学科设计优化模型进行了求解。多学科设计优... 详细信息

为了确保发动机转子式机油泵整体性能提高,以转子式机油泵泵油性能、质量以及抗冲击性能为目标函数建立了多学科设计优化模型,并充分考虑了各学科之间的耦合效应,采用自适应混沌优化算法对多学科设计优化模型进行了求解。多学科设计优化结果表明:转子式机油泵供油量增加了2.43%,质量减少了10.0%,位移变形减少了16.3%,整体性能提高了8.2%。优化前后转子式机油泵转子齿面交变有效应力对比试验结果表明:优化后机油泵齿顶所受最大应力降低至150 MPa左右,小于屈服极限。

关键词：内燃机转子式机油泵多学科优化设计自适应混沌优化算法

水介质中α,α-双(4-羟基香豆素-3-基)甲苯的洁净合成

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有机化学 2005年第8期25卷 926-929页

作者：王静史达清庄启亚王香善屠树江徐州师范大学化学系

在水介质中三乙基苄基氯化铵(TEBA)存在下,芳醛与4-羟基香豆素反应为α,α-双(4-羟基香豆素-3-基)甲苯提供了一种快速、方便、高效和洁净的合成方法.

关键词：水介质 α,α-(4-羟基香豆素-3-基)甲苯绿色合成三乙基苄基氯化铵芳醛 4-羟基香豆素

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基于多因素影响的数控铣床定位误差研究

组合机床与自动化加工技术 2018年第4期 80-83,87页

作者：曾超王湘江南华大学机械工程学院湖南衡阳421000

定位误差测量的可靠程度决定了能否有效提高数控铣床的定位精度。采用Laser XL-30激光干涉仪对MVC850B数控铣床进行定位误差测量实验,研究了不同条件因素对定位误差的影响。在实验测量过程中,首先利用环境参数补偿方法进行试验对比,得... 详细信息

定位误差测量的可靠程度决定了能否有效提高数控铣床的定位精度。采用Laser XL-30激光干涉仪对MVC850B数控铣床进行定位误差测量实验,研究了不同条件因素对定位误差的影响。在实验测量过程中,首先利用环境参数补偿方法进行试验对比,得出环境参数(包括气温、气压、湿度)对定位误差测量的影响。然后以进给速度、测量间距、加工时间为自变量因素,反向间隙误差和螺距累积误差作为响应结果,利用三因素双目标统计分析方法,得到不同因素对响应结果的影响程度,同时发现数控铣床定位误差与自变量的变化关系。最后通过观察某一段时间内定位误差的概率分布曲线,进一步得到误差测量的可靠度和机床运动精度保持性,预测出机床可能出现的误差位置,可有效地采取措施提高数控铣床定位精度。

关键词：定位误差环境参数概率分布曲线可靠度