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Industrial-scale investigations on effects of tertiary-air declination angle on combustion and steam temperature characteristics in a 350-MW supercritical down-fired boiler

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Frontiers in Energy 2021年第1期15卷 132-142页

作者： Xiaoguang li lingyan ZENG Hongye liU Yao li Yifu li Yunlong ZHAO Bo JIAO Minhang SONG Shaofeng ZHANG Zhichao CHEN zhengqi li School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China Guizhou Wanfeng Electric Power Co. Ltd.Xingyi 562400China Guizhou Xingyi Project Department Huadian United(Beijing)Power Engineering Co.Ltd.Xingyi 562400China

Industrial-scale experiments were conducted to study the effects of tertiary air declination angle(TDA)on the coal combustion and steam temperature characteristics in the first 350-MW supercritical down-fired boiler in China with the multiple-injection and multiple-staging combustion(MIMSC)technology at medium and high *** experimental results indicated that as the TDA increased from 0°to 15°,the overall gas temperature in the lower furnace rose and the symmetry of temperature field was *** ignition distance of the fuel-rich coal/air flow *** near-burner region,the concentration of O2 decreased while the concentrations of CO and NO *** concentration of NO decreased in near-tertiary-air *** carbon in fly ash decreased significantly from 8.40%to 6.45%at a load of 260 *** a TDA of 15°,the ignition distances were the shortest(2.07 m and 1.73 m)at a load of 210 MW and 260 MW,*** main and reheat steam temperatures were the highest(557.2℃ and 559.4℃ at a load of 210 MW,558.4℃ and 560.3℃ at a load of 260 MW).The carbon in fly ash was the lowest(4.83%)at a load of 210 *** changing the TDA from 15°to 25°,the flame kernel was found to move downward and the main and reheat steam temperatures dropped *** change of TDA has little effect on NO_(x) emissions(660–681 mg/m^(3) at 6%O_(2)).In comprehensive consideration of the pulverized coal combustion characteristics and the unit economic performance,an optimal TDA of 15°is recommended.

关键词： supercritical down-fired boiler industrialscale experiment tertiary air declination angle coal combustion steamtemperature

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Influence of different oil feed rate on bituminous coal ignition in a full-scale tiny-oil ignition burner

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Frontiers in Energy 2013年第3期7卷 406-412页

作者： Chunlong liU Qunyi ZHU zhengqi li Qiudong ZONG, Xiang ZHANG, Zhichao CHEN zhengqi li Qiudong ZONG Xiang ZHANG Zhichao CHEN School of Energy Science and Engineering Harbin Institute of Technology Harbin 150001 China

To reduce oil consumption during firing-up and partial-load operation, a tiny-oil ignition burner has been recommended. Through reacting-flow experiments performed on a full-scale experimental setup, the influence of different oil flow rates on bituminous coal combustion as well as flow rates without coal feed was analyzed. The ignition burner is identical to that normally used in an 800 MWe utility boiler. Under operating conditions with flow rates of 50, 100, and 150kg/h, gas temperature distribu- tions were measured in the burner. At the equivalent measuring points at the exits of the first and second combustion chambers, these distributions remained almost unchanged under a constant coal feed rate of 4t/h. However on the burner centerline, distributions increased slightly with increasing flow rate. Different gas concentrations were measured at the center of the burner exit. For instance, the 02 concentration at the burner exit varied from 0.01% to 0.31% whereas CO concentrations were more than 10000 ppm. At the same coal feed rate of 4 t/h, burner resistances are 480, 600, and 740 Pa for oil flow rates of 50, 100, and 150 kg/h, respectively.

关键词： ignition coal burner boiler oil flow rate

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Numerical simulation of bituminous coal combustion in a fullscale tiny-oil ignition burner： Influence of excess air ratio

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Frontiers in Energy 2012年第3期6卷 296-303页

作者： zhengqi li Chunlong liU Xiang ZHANG lingyan ZENG Zhichao CHEN School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

The progression of ignition was numerically simulated with the aim of realizing a full-scale tiny-oil ignition burner that is identical to the burner used in an 800 MWe utility boiler. The numerical simulations were conducted for four excess air ratios, 0.56, 0.75, 0.98 and 1.14 （corresponding to primary air velocities of 17, 23, 30 and 35 m/s, respectively）, which were chosen because they had been used previously in practical experiments. The numerical simulations agreed well with the experimental results, which demonstrate the suitability of the model used in the calculations. The gas temperatures were high along the center line of the burner for the four excess air ratios. The flame spread to the bumer wall and the high- temperature region was enlarged in the radial direction along the primary air flow direction. The O2 concentrations for the four excess air ratios were 0.5%, 1.1%, 0.9% and 3.0% at the exit of the second combustion chamber. The CO peak concentration was very high with values of 7.9%, 9.9%, 11.3% and 10.6% for the four excess air ratios at the exit of the second combustion chamber.

关键词： numerical simulation tiny-oil ignition burner,pulverized coal temperature field

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Submucosal tunneling endoscopic resection of an exogenic esophageal mass in the mediastinum(with video)

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Gastroenterology Report 2021年第3期9卷 272-273,I0003页

作者： zhengqi li Yong liu lizhou Dou Yueming Zhang Guiqi Wang Department of Endoscopy National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingP.R.China

Introduction Submucosal tunneling endoscopic resection(STER)for the treatment of upper gastrointestinal submucosal tumors originating from the muscularis propria was first introduced by Xu et al.[1]in *** has been demonstrated to be safe and effective for treating small(<3.5 cm)esophageal ***,sometimes the esophageal leiomyoma may be a giant mass and protrude into the mediastinum.

关键词：外生性食管肿瘤 esophageal

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Numerical simulation of combustion characteristics at different coal concentrations in bituminous coal ignition in a tiny-oil ignition burner

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Frontiers in Energy 2013年第2期7卷 255-262页

作者： Chunlong liU Qunyi ZHU zhengqi li Qiudong ZONG Yiquan XIE lingyan ZENG School of Energy Science and Engineering Harbin Institute ofTechnology Harbin 150001 China

With the objective of producing a full-scale tiny-oil ignition burner, identical to the burner used in an 800 MWe utility boiler, numerical simulations were performed using Fluent 6.3.26 to study the progress of ignition for four coal concentration settings covering sub- operation conditions prevailing during the experiments performed with the burner. The numerical simulations conformed to the experimental results, demonstrating the suitability of the model used in the calculations. Simula- tions for a coal concentration of 0.40 kg/kg corresponding to a single burner operating at its rated output were also conducted, which indicated that gas temperatures along the burner centerline were high. As gas flowed to the burner nozzle, the high-temperature region expanded, ensuring a successful pulverized-coal ignition. With increasing coal concentration （0.08-0.40 kg/kg）, the gas temperature along the burner centerline and at the first and second combustion chamber exits decreased at the equivalent radial points. At the center of the second combustion chamber exit, the O2 concentrations were almost depleted for the five coal concentrations, while the CO concentrations peaked.

关键词： numerical simulation tiny-oil ignition burner pulverized coal temperature field

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

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Frontiers in Energy 2021年第1期15卷 68-77页

作者： Rong YAN Zhichao CHEN Shuo GUAN zhengqi li School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

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 x/d = 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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Application of Advanced Measurement Technology and Equipment in Transmission Manufacturing

Application of Advanced Measurement Technology and Equipment...

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2019中国汽车工程学会年会

作者： Geng Xiaolong Yang Hongbing li zhengqi li Yingsu Dongfeng GETRAG Transmission Co. LtdManufacture Engineering Department

In recent years many new measurement technologies have sprang up in automobile manufacturing field,the main characters of which are that,they can complete the measurement of workpieces between operations with high speed,high efficiency,high accuracy and high flexibility,and thus guarantee the manufacture *** of advanced measurement technologies in vehicle transmission are introduced,*** technologies of transmission shafts,gears and housing.

关键词： transmission advanced measurement technology

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提高年循环效率的永磁同步发电机-齿轮传动系统机电协同设计

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机械工程学报 2024年第1期60卷 296-308页

作者：李峥琪刘长钊宋健王磊重庆大学高端装备机械传动全国重点实验室重庆400044 重庆大学机械与运载工程学院重庆400030

为实现永磁同步风力发电机组轻量化、高年循环效率的设计目标,提出了一种永磁同步发电机-齿轮传动系统机电协同参数优化设计方法。首先建立风轮计算模型,以风电场实测的年风速工况作为风力发电机组的运行工况。接着建立齿轮传动系统的... 详细信息

为实现永磁同步风力发电机组轻量化、高年循环效率的设计目标,提出了一种永磁同步发电机-齿轮传动系统机电协同参数优化设计方法。首先建立风轮计算模型,以风电场实测的年风速工况作为风力发电机组的运行工况。接着建立齿轮传动系统的损耗模型,并基于有限元建立永磁同步发电机饱和磁链模型、转矩模型和损耗模型。在此基础上,为最大限度地发挥各参数下发电机组的效率潜力,采用非线性效率最优电流分配策略对发电机的控制电流进行优化。最后在发电机电磁约束、齿轮几何和强度约束、连续传动约束条件下,以发电机和齿轮的参数作为优化变量,以永磁同步发电机-齿轮传动系统的总质量和年循环风速工况下的总损耗作为目标函数,利用NSGA-Ⅱ算法对目标函数进行优化。该过程优化中嵌套优化,整个过程通过脚本自动化运行,最大程度地降低了系统的损耗和质量,减少了时间成本。基于上述方法对8 MW永磁同步发电机-齿轮传动系统进行优化,优化后系统总质量降低了40.2%,系统年循环损耗减少了461 562.53 kW·h,表明该方法有效地降低了系统的质量且提高了年循环效率。

关键词：永磁同步风力发电机组轻量化年循环效率机电协同设计参数优化

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The technique of measuring absolute spectral responsivity of InGaAs detector based on cryogenic radiometer

The technique of measuring absolute spectral responsivity of...

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2nd International Symposium on Advanced Optical Manufacturing and Testing Technologies

作者： Fan Jihong Yang Zhaoji Hou Xiqi Qin Yan li zhengqi (Xi’an Institute of Applied Optics)

＜正＞The spectral responsivity is one of the important parameters of *** the development of infrared detect technique, infrared detector need to be better and better,so measuring the absolute spectral responsivity accurately is very *** paper mainly introduces how to measure the absolute spectral responsivity of InGaAs detector precisely and make the measurement be based on cryogenic radiometer. We use cavity pyroelectric detector whose relative spectral responsivity should be measured ahead of time to calibrate the relative spectral responsivity of InGaAs detector in serial wavelength by means of establishing infrared spectral responsivity facility. Then we make use of silicon detector to calibrate the absolute spectral responsivity of InGaAs detector at *** silicon detector absolute spectral responsivity at 900nm is calibrated by cryogenic radiometer in association with visible spectral responsivity *** the absolute spectral responsivity of InGaAs detector at every wavelength can be get by calculating. At last the paper gives the measuring result and analyzes the uncertainty.

关键词： cavity pyroelectric detector cryogenic radiometer InGaAs detector

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径向浓淡旋流燃烧器气固流动特性的实验研究及其对燃烧的影响

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中国电机工程学报 1999年第5期19卷 18-23,43页

作者：李争起孙锐孙绍增吴少华秦裕琨哈尔滨工业大学能源科学与工程学院

在气固两相实验台上采用三维ＰＤＡ系统对径向浓淡旋流煤粉燃烧器及蜗壳燃烧器出口的气固流动特性进行了试验，发现前者在中心回流区边缘附近形成了较高的颗粒浓度，中心回流区中颗粒浓度也较大，后者在中心回流区及边缘附近颗粒浓度较... 详细信息

在气固两相实验台上采用三维ＰＤＡ系统对径向浓淡旋流煤粉燃烧器及蜗壳燃烧器出口的气固流动特性进行了试验，发现前者在中心回流区边缘附近形成了较高的颗粒浓度，中心回流区中颗粒浓度也较大，后者在中心回流区及边缘附近颗粒浓度较小，壁面区域则较大。分析了两相流动特性对燃烧器性能的影响，并通过工业试验进行了验证，表明径向浓淡旋流煤粉燃烧器是一种同时具有高效、稳燃、低污染、防止结渣和防止高温腐蚀的新一代旋流燃烧器。

关键词：锅炉旋流燃烧器气固流动燃烧器燃烧

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