福建无烟煤粒度分布对循环流化床锅炉燃烧影响的工业实验

作者在一台20t/h循环流化床锅炉上进行了燃烧三种不同粒度分布的福建Ⅱ类无烟煤的工业实验，取得颗粒平均粒径与悬浮段颗粒浓度、飞灰含炭量以及悬浮段颗粒与炉膛温度等关系曲线。有关数据与结论对燃烧福建无烟煤的CFB锅炉的设计运行具有参考价值。 同时，作者对提高CFB锅炉热效率及降低飞灰含碳量提出了几点建议。     

石灰石粒度分布对燃用福建无烟煤CFB锅炉炉内脱硫的影响

在一台35t/hCFB锅炉上进行了炉内加石灰石脱硫工业实验研究，得出燃烧福建Ⅱ类无烟煤时石灰石粒度分布对脱硫效率和床温等运行参数的影响。对实验结果进行分析并提出了燃用福建Ⅱ类无烟煤的CFB锅炉实际采用炉内脱硫工艺所适用的石灰石粒度分布。     

激光衍射仪在雾化油滴粒度测量上的应用

本文简述了应用以Fraunhoffer几何光学理论为基础的LPI—2型激光衍射粒径仪测量雾化油滴尺寸和分布特性,阐明了这一应用对深入开展油雾化研究的重要意义。     

柴油机轴功率激光测试技术的研究

主要论述激光斑纹和激光多普勒测量技术在扭矩测量中的应用。激光斑纹现象产生于从粗糙表面粗散射相干激光束的干涉。对于粗糙表面形成特定的斑纹图样,他与被测表面同步运动。周期的靶标运动,特别是回转运动,引起斑纹图样周期性重复。根据这一性质,作者介绍一种应用于旋转机械的非接触式激光扭矩测试技术的工作原理。     

激光衍射粒子测试系统的模块设计

介绍了激光衍射料子测试系统的程序模块设计。该模块设计主要采用了面 向对象的程序设计方法,应用程序全部为图形用户界面,使系统具有良好的可扩充性和可持续发展性。系统的功能模块主要包括：件服务模块、测试设置模块、系统调整模块、实时采集模块、数据处理模块、帮助模块等几个部分,这些模块相互独立而又相辅助相成,使系统在Win95（Win98）下能够比较稳定地运行。通过大量的试验证明,该激光衍射粒子测试系统具有应用范围广,数据处理快,性能可靠等特点。     

柴油机喷雾速度场的激光相位多普勒测试

本文介绍了一种测试柴油机喷雾速度场的新手段－激光相位多普勒测试技术。进行了稳态下喷雾速度场的测试，对测试结果进行了分析，为柴油机喷雾的理论研究提供了试验依据，加深了对柴油机喷雾内部微观情况的了解。     

汽轮发电机组轴系标高激光多点同时测试系统及其应用

为解决大型汽轮发电机组轴系热态标高变化测量问题,开发了基于激光和PSD技术的轴系标高测试系统.介绍了轴承标高测量原理和PSD工作原理,分析了影响标高测量精度的因素,提出了相应的解决办法,并给出了性能测试数据及应用实例.实测结果表明:系统分辨率为1 μm,测量精度为15μm,能连续在线同时监测大型汽轮发电机组各轴承绝对标高和相对标高变化;现场实测数据稳定、可靠,可为振动故障诊断提供依据,为轴系标高调整提供参考.     

激光全息干涉测温技术的研究

本文对用激光全息干涉技术测量内燃机燃烧室内温度场进行了研究。文中论述了激光全息干涉技术的基本原理,两次曝光法技术,测量光路的布置,实验装置的安排和实验步骤,反演计算等一系列技术问题,并提供了在模型燃烧室中温度场的测量结果,据此可以定量,精确地了解燃烧室内的温度分布。为实机测量和进一步研究燃油的蒸发,混合及燃烧规律打下良好的基础。     

黄河悬移质泥沙粒度分布动态图像法的应用评价

采用动态图像法和激光法对黄河干流悬移质泥沙样品进行泥沙粒度分析,构建了动态图像法与激光法粒度成果之间的相关性。利用激光粒度分析技术得出粒度分布的中值粒径D50,再利用粒度粒形分析技术分析,结果显示动态图像法粒度成果与激光法粒度成果在不同级配之间的关系基本一致,动态图像法获得的粒度分布的D50通常大于激光法获得的D50。     

空气滤清器实用效果的测试分析技术

为评价内燃机空气滤清器的实用效果（发动机使用中的滤清效率，滤后含尘浓度及粒度分布）开发出一套直接从运行发动机上采样和进行分析的测试方法。该技术已应用于新型沙漠车空滤器的性能评定。     

多波长消光法粒径测量下限影响因素分析

介绍了根据Lambert-Beer定理并采用多波长消光法测量颗粒粒径分布的方法。提出了基于数值模拟和数理统计对多波长消光法粒径测量下限进行估计的方法。通过数值模拟分析讨论了入射光波长、颗粒相对折射率和透光率对粒径测量下限的影响。研究为多波长消光法粒径测量在实际应用中的可行性提供了指导。     

Simultaneous effect of particle size and location on stress development in the electrodes of lithium-ion batteries

In this study, stress generation at the electrode in Li-ion batteries was studied using a two-dimensional cell-scale model that includes multiple active particles during galvanostatic discharge. Numerical simulations were performed using an electrochemical–mechanical coupled model to elucidate the simultaneous effects of particle size and location, lithium intercalation kinetics and binder constraints on the stress. The simulation results showed that when different sizes of particle are considered in the electrode, the small particles were discharged more than the large particles, resulting in higher level of stress in the smaller particles. In addition, the closer the particles were located to the separator, the larger the stresses that were developed in those particles. Therefore, a layered structure, where the particle size gradually increases as the distance from the particles to the separator decreases, can alleviate stress on the electrode. When binder constraints were considered for the electrode particles, the stress was increased at the anode and alleviated at the cathode upon discharge. This indicates that the effect of mechanical constraints on stress generation in the particles differs in the lithiation and delithiation process.     

喷嘴液滴雾化细度和喷雾角测量装置的研究

在FAM激光测粒仪的基础上,添加雾化角测量装置,建立了喷嘴雾化全性能试验台用以全面评价喷嘴的雾化性能。利用USB接口将喷嘴雾化的图像信号输入计算机,使用自己研制的图像处理软件来计算喷嘴雾化的雾化角。实现了喷嘴喷雾的雾化粒度和雾化角的快速同步测量,对装置 的可行性和实用性进行了验证。     

Single particle ignition and combustion of anthracite,semi-anthracite and bituminous coals in air and simulated oxy-fuel conditions

A fundamental investigation has been conducted on the combustion behavior of single particles (75–150 μm) of four coals of different ranks: anthracite, semi-anthracite, medium-volatile bituminous and high-volatile bituminous. A laboratory-scale transparent laminar-flow drop-tube furnace, electrically-heated to 1400 K, was used to burn the coals. The experiments were performed in different combustion atmospheres: air (21%O₂/79%N₂) and four simulated dry oxy-fuel conditions: 21%O₂/79%CO₂, 30%O₂/70%CO₂, 35%O₂/65%CO₂ and 50%O₂/50%CO₂. The ignition and combustion of single particles was observed by means of three-color pyrometry and high-speed high-resolution cinematography to obtain temperature–time histories and record combustion behaviors. On the basis of the observations made with these techniques, a comprehensive examination of the ignition and combustion behaviors of these fuels was achieved. Higher rank coals (anthracite and semi-anthracite) ignited heterogeneously on the particle surface, whereas the bituminous coal particles ignited homogeneously in the gas phase. Moreover, deduced ignition temperatures increased with increasing coal rank and decreased with increasing oxygen concentrations. Strikingly disparate combustion behaviors were observed depending on the coal rank. The combustion of bituminous coal particles took place in two phases. First, volatiles evolved, ignited and burned in luminous enveloping flames. Upon extinction of these flames, the char residues ignited and burned. In contrast, the higher rank coal particles ignited and burned heterogeneously. The replacement of the background N₂ gas of air with CO₂ (i.e., changing from air to an oxy-fuel atmosphere) at the same oxygen mole fraction impaired the intensity of combustion. It reduced the combustion temperatures and lengthened the burnout times of the particles. Increasing the oxygen mole fraction in CO₂ to 30–35% restored the intensity of combustion to that of air for all the coals studied. Volatile flame burnout times increased linearly with the volatile matter content in the coal in both air and all oxygen mole fractions in CO₂. On the other hand, char burnout times increased linearly or quadratically versus carbon content in the coal, depending on the oxygen mole fraction in the background gas.     

A novel light fluctuation spectrum method for in-line particle sizing

This paper discusses two problems in in-line particle sizing when using light fluctuation method. First, by retrieving the ratio of particle concentrations at different time, the intensity of incident light is obtained. There exists narrow error between the calculated and pre-detected value of the intensity of incident light. Secondly, by combining spectrum analysis with Gregory’s theory, a multi-sub-size zone model is proposed, with which the relationship between the distribution of turbidity and the particle size distribution (PSD) can be established, and an algorithm developed to determine the distribution of turbidity. Experiments conducted in the laboratory indicate that the measured size distribution of pulverized coal conforms well with the imaging result.     

Effect of particle size on sodium distribution and sodium removal by water washing of Zhundong coal

The utilization of Zhundong (ZD) coal has been limited by its high sodium content. In the paper, the effect of particle size on the distribution of the sodium contained in the coal and the sodium removal from the coal was addressed. The results indicate that the water-soluble sodium content and insoluble sodium content increased and the acid-soluble sodium decreased with increasing particle size. The occurrence modes of the sodium contained correlate closely to the properties of ZD coal. The water-soluble sodium and water-soluble chlorine contained in ZD coal may exist in the form of sodium chloride. Due to the competitive effects between adsorbing capability of the leachate and the diffusing capability of sodium ion, the removal sodium rate increases first and then decreases with increasing particle size.     

Effect of particle size on coal char----NO reaction

Surface nitrogen complex formation upon reaction of coal char with NO at 600°C was studied by X-ray photoelectron spectroscopy. Particle size had a noticeable effect on the magnitude of changes, which was observed on the surface of the coal char in the nitrogen functional group. The surface increased its -NO, pyridine-N-oxide, and -NO₂ functional group contents with a decrease in particle size. The chemisorption processes of NO molecules on the char were simulated using the ab initio Hartree–Fock method and density functional theory. Molecular modeling was applied to determine the thermodynamics of the reactions. Mechanisms were proposed to explain the formation of the -NO, pyridine-N-oxide, and -NO₂ functional groups at 600°C.     

松花江流域泥沙颗粒分形性研究

研究流域泥沙有利于分析泥沙来源、泥沙运动及河床演变等,采取有针对性的治理措施对控制泥沙非常有利。为此,根据分形理论,通过MS2000激光粒度分析仪分析了松花江流域晨明、古城子、哈尔滨、佳木斯、南岔、铁力、延寿七个水文站泥沙粒度分布的分形性。结果表明,松花江流域7个测站泥沙粒度的分维值在2.201~2.391之间,所对应的相关系数均在0.858以上,基本保持了良好的统计自相似性,分维值与泥沙颗粒组成、传统粒度参数的相关关系基本符合经验数据。     

生物柴油燃料对柴油机不同负荷工况微粒粒度分布的影响

利用TS13090 EEPS微粒粒度测试系统,试验研究了生物柴油、石化柴油燃料微粒稳态工况下的粒度分布特征.研究结果表明,高压共轨柴油机微粒排放粒径绝大部分在300 nm以下,生物柴油、石化柴油燃料微粒粒度分布均呈双峰结构,核态蜂值区域在10 nm附近,积聚态峰值区域在60 nm附近.生物柴油燃料微粒排放以小粒径核态微...     

基于潜热填充床的双向变粒径结构热性能分析

为改善潜热填充床的储/释热性能,提出了一种优化的双向变粒径球形储热单元填充结构,并基于实验室搭建的中高温相变储热实验系统,模拟分析了该结构相较于传统结构对填充床储/释热效率和时间的影响。结果表明,在保证相同储热量下,双向变粒径结构能够有效的提升储/释热效率,延长有效热流输出的时间。其中20:30:20（体积比1:1:1）的双向变粒径结构输出有效热流的时间为6685 s,放热功率为846.1 W,相对于其他的填充结构,综合热性能最好。该研究能够为进一步实现储热系统能量的高效稳定与梯度利用做铺垫。