资源类型

期刊论文 499

年份

2023 37

2022 28

2021 37

2020 19

2019 20

2018 19

2017 25

2016 17

2015 17

2014 25

2013 27

2012 14

2011 24

2010 35

2009 22

2008 43

2007 53

2006 9

2005 6

2004 6

展开 ︾

关键词

温度 3

温度控制 3

燃烧特性 3

低温SOFC 2

内燃机 2

力学性能 2

大气温度 2

技术路线 2

模糊控制 2

温度分布 2

燃烧性能 2

生物质 2

碳中和 2

高温气冷堆 2

(美国) 核管理委员会 1

10kV高压电力电缆 1

6016 合金 1

Al-Cr203体系 1

Al@AP/PVDF纳米复合材料 1

展开 ︾

检索范围:

排序: 展示方式:

Techno-economic comparison of three technologies for pre-combustion CO

Simon Roussanaly, Monika Vitvarova, Rahul Anantharaman, David Berstad, Brede Hagen, Jana Jakobsen, Vaclav Novotny, Geir Skaugen

《化学科学与工程前沿(英文)》 2020年 第14卷 第3期   页码 436-452 doi: 10.1007/s11705-019-1870-8

摘要: This paper compares the techno-economic performances of three technologies for CO capture from a lignite-based IGCC power plant located in the Czech Republic: (1) Physical absorption with a Rectisol-based process; (2) Polymeric CO -selective membrane-based capture; (3) Low-temperature capture. The evaluations show that the IGCC plant with CO capture leads to costs of electricity between 91 and 120 €·MWh , depending on the capture technology employed, compared to 65 €·MWh for the power plant without capture. This results in CO avoidance costs ranging from 42 to 84 €· , mainly linked to the losses in net power output. From both energy and cost points of view, the low-temperature and Rectisol based CO capture processes are the most efficient capture technologies. Furthermore, partial CO capture appears as a good mean to ensure early implementation due to the limited increase in CO avoidance cost when considering partial capture. To go beyond the two specific CO -selective membranes considered, a cost/membrane property map for CO -selective membranes was developed. This map emphasise the need to develop high performance membrane to compete with solvent technology. Finally, the cost of the whole CCS chain was estimated at 54 €· once pipeline transport and storage are taken into consideration.

关键词: carbon capture and storage (CCS)     techno-economic comparison     pre-combustion capture     physical solvent     low-temperature capture    

dioxide over porous solid adsorbents lithium silicate, lithium aluminate and magnesium aluminate at pre-combustion

P. V. Korake, A. G. Gaikwad

《化学科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 215-226 doi: 10.1007/s11705-010-1012-9

摘要: The capturing process for carbon dioxide over porous solid adsorbents such as lithium silicate, lithium aluminate, and magnesium aluminate at pre- combustion temperatures was studied. Lithium silicate was prepared by the sol gel and solid fusion methods. The lithium silicate adsorbent was characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), nuclear magnetic resonance (NMR), and surface area. The capturing of carbon dioxide over lithium silicate, lithium aluminate, and magnesium aluminate was explored at different experimental conditions such as exposure time, temperature variation, and exposure carbon dioxide pressure. The capturing process for carbon dioxide was investigated over these adsorbents with variation of their metal mole ratios. The effect of the addition of (promoter) sodium, potassium, and cesium in the lithium silicate adsorbent was explored to investigate the variation of the capture of carbon dioxide over these adsorbents.

关键词: capturing CO2     lithium silicate     lithium aluminate     magnesium aluminate    

The capture of carbon dioxide by transition metal aluminates, calcium aluminate, calcium zirconate, calcium silicate and lithium zirconate

Ganesh TILEKAR, Kiran SHINDE, Kishor KALE, Reshma RASKAR, Abaji GAIKWAD

《化学科学与工程前沿(英文)》 2011年 第5卷 第4期   页码 477-491 doi: 10.1007/s11705-011-1107-y

摘要: The capture of CO by transition metal (Mn, Ni, Co and Zn) aluminates, calcium aluminate, calcium zirconate, calcium silicate and lithium zirconate was carried out at pre- and post-combustion temperatures. The prepared metal adsorbents were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), surface area analysis and acidity/alkalinity measurements. The different experimental variables affecting the adsorbents ability to capture CO , such as the mol ratio of metal ions, the pressure of CO , the exposure time and the temperature of the adsorbent were also investigated. Calcium zirconate captured 13.85 wt-% CO at 650°C and 2.5 atm and calcium silicate captured 14.31 wt-% at 650°C. Molecular sieves (13X) and carbon can only capture a negligible amount of CO at high temperatures (300°C–650°C). However, the mixed metal oxides captured reasonable amount of CO at these higher temperatures. In addition, calcium aluminate, calcium zirconate, calcium silicate and lithium zirconate adsorbents captured CO at both pre and post-combustion temperatures. The trend for the amount of captured carbon dioxide over the adsorbents was calcium aluminate

关键词: captured CO2     pre-combustion temperature     characterization     calcium silicate     calcium zirconate    

Influence of temperature on cam-tappet lubrication in an internal combustion engine

CHANG Qiuying, YANG Peiran, WANG Jing, CHEN Quanshi

《机械工程前沿(英文)》 2007年 第2卷 第4期   页码 489-492 doi: 10.1007/s11465-007-0085-8

摘要: The transient thermo-elastohydrodynamic (TEHL) lubrication simulation and isothermal elastohydrodynamic (EHL) simulation were performed on the exhausting cam-tappet friction pair of an internal combustion engine. Although by employing the two models the center pressure, the thickness of the lubricant film and friction coefficient obtained were similar in the changing trend during a rotating cycle, the parameters make a great difference, especially for the thickness of the lubricant film; the TEHL was four times thicker than the EHL. These results show that the temperature should not be neglected in the study of the lubrication of cam-tappet pairs.

关键词: coefficient     combustion     isothermal elastohydrodynamic     temperature     thickness    

Impact of oxygen enriched combustion on the performance of a single cylinder diesel engine

K. RAJKUMAR, P. GOVINDARAJAN

《能源前沿(英文)》 2011年 第5卷 第4期   页码 398-403 doi: 10.1007/s11708-011-0157-7

摘要: In the present experiment, a computerized single cylinder diesel engine with a data acquisition system was used to study the effects of oxygen enriched combustion technology (OECT) on the performance characteristics. The use of different levels of oxygen-enriched air was compared with respect to percentage load. Increasing the oxygen content in the air leads to faster burn rates and increases the combustibility at the same stoichiometry (oxygen-to-fuel ratio). These effects have the potential to increase the thermal efficiency and specific power output of a diesel engine. The power increases considerably with oxygen enrichment. In addition, oxygen enrichment can also be considered as a way to reduce the sudden loss in power output when the engine operates in a high load condition. Assessed high combustion temperature from the oxygen enriched combustion leads to high combustion efficiency. OECT reduces the volume of flue gases and reduces the effects of greenhouse effects. Engine tests were conducted in the above said engine for different loads and the following performance characteristics like brake power (BP), specific fuel consumption (SFC), mean effective pressure, brake thermal efficiency, mechanical efficiency, and exhaust gas temperature were studied. The objective of this paper is to address, in a systematic way, the key technical issues associated with applying OECT to single cylinder diesel engines.

关键词: oxygen enriched combustion     exhaust gas temperature     brake power (BP)     specific fuel consumption (SFC)    

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

Xiaoguang LI, Lingyan ZENG, Hongye LIU, Yao LI, Yifu LI, Yunlong ZHAO, Bo JIAO, Minhang SONG, Shaofeng ZHANG, Zhichao CHEN, Zhengqi LI

《能源前沿(英文)》 2021年 第15卷 第1期   页码 132-142 doi: 10.1007/s11708-020-0803-z

摘要: 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 loads. The 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 enhanced. The ignition distance of the fuel-rich coal/air flow decreased. In near-burner region, the concentration of O decreased while the concentrations of CO and NO increased. The concentration of NO decreased in near-tertiary-air region. The carbon in fly ash decreased significantly from 8.40% to 6.45% at a load of 260 MW. At 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, respectively. The main and reheat steam temperatures were the highest (557.2°C and 559.4°C at a load of 210 MW, 558.4°C and 560.3°C at a load of 260 MW). The carbon in fly ash was the lowest (4.83%) at a load of 210 MW. On changing the TDA from 15° to 25°, the flame kernel was found to move downward and the main and reheat steam temperatures dropped obviously. The change of TDA has little effect on NO emissions(660–681 mg/m at 6% O ). 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     industrial-scale experiment     tertiary air declination angle     coal combustion     steam temperature    

Modification of premixed combustion in shear layers by grid turbulence

MU Kejin, WANG Yue, ZHANG Zhedian, NIE Chaoqun

《能源前沿(英文)》 2007年 第1卷 第2期   页码 245-250 doi: 10.1007/s11708-007-0034-6

摘要: The influence of grid turbulence on the shear layer of a jet and the premixed flames embedded in it was investigated in the present study. The velocity field of the jet was measured by using hot-wire anemometry. It was found that grid turbulence reduced turbulence intensities in the shear layer and suppressed low frequency fluctuation. Moreover, the energy contained in small-scale fluctuation was increased and turbulence became homogeneous. The results indicate that grid turbulence inhibits the formation of a large-scale coherent structure in the shear layer. Flame temperature was measured by using a compensated fine-wire thermocouple. It was found that grid turbulence reduced low frequency fluctuation of the flame fronts, increased the small-scale wrinkles and elevated the mean temperature of the flame zone. The results show that grid turbulence can enhance and stabilize premixed flames in shear flow.

关键词: homogeneous     fine-wire thermocouple     temperature     hot-wire anemometry     premixed    

Numerical simulation of combustion characteristics at different coal concentrations in bituminous coal

Chunlong LIU, Qunyi ZHU, Zhengqi LI, Qiudong ZONG, Yiquan XIE, Lingyan ZENG

《能源前沿(英文)》 2013年 第7卷 第2期   页码 255-262 doi: 10.1007/s11708-013-0255-9

摘要: 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. Simulations 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 O 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    

Numerical simulation of bituminous coal combustion in a full-scale tiny-oil ignition burner: influence

Zhengqi LI, Chunlong LIU, Xiang ZHANG, Lingyan ZENG, Zhichao CHEN

《能源前沿(英文)》 2012年 第6卷 第3期   页码 296-303 doi: 10.1007/s11708-012-0191-0

摘要: 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 burner wall and the high-temperature region was enlarged in the radial direction along the primary air flow direction. The O 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    

Nonlinear analysis of pre-tensioned glass wall facade by stability function with initial imperfection

Siu-Lai CHAN, Yaopeng LIU, Andy LEE,

《结构与土木工程前沿(英文)》 2010年 第4卷 第3期   页码 376-382 doi: 10.1007/s11709-010-0086-2

摘要: Pre-tensioned high strength trusses using alloy steel bar are widely used as glass wall supporting systems because of the high degree of transparency. The breakage of glass panes in this type of system occurs occasionally, likely to be due to error in design and analysis in addition to other factors like glass impurity and stress concentration around opening in a spider system. Most design does not consider the flexibility of supports from finite stiffness of supporting steel or reinforced concrete beams. The resistance of lateral wind pressure of the system makes use of high tension force coupled with the large deflection effect, both of which are affected by many parameters not generally considered in conventional structures. In the design, one must therefore give a careful consideration on various effects, such as support settlement due to live loads and material creep, temperature change, pre-tension force, and wind pressure. It is not uncommon to see many similar glass wall systems fail in the wind load test chambers under a design wind speed. This paper presents a rigorous analysis and design of this type of structural systems used in a project in Hong Kong, China. The stability function with initial curvature is used in place of the cubic function, which is only accurate for linear analysis. The considerations and analysis techniques are believed to be of value to engineers involved in the design of the structural systems behaving nonlinearly.

关键词: tension system     glass wall     nonlinear analysis     pre-tensioning     second-order analysis    

Influence of mineral transformation on emission of particulate matters during coal combustion

LIU Xiaowei, XU Minghou, YU Dunxi, GAO Xiangpeng, CAO Qian, HAO Wei

《能源前沿(英文)》 2007年 第1卷 第2期   页码 213-217 doi: 10.1007/s00000-007-0028-4

摘要: Combustion of pulverized coal was studied in a drop tube furnace to understand coal mineral properties with the emission of particulate matters (PM). Experimental conditions were selected as follows: coal particle size was smaller than 63 μm; reaction temperature was 1 100vH, 1 250vH and 1 400vH respectively; oxygen content was 20% and 50% respectively. PM was collected with a 13-stagelow pressure impactor (LPI) having an aerodynamic cut-off diameter ranging from 10.0 μm to 0.03 μm for a size-segregated collection. Such properties as concentration, particle size distribution and elemental composition of PM were investigated. The experimental results indicate that the emitted PM has a bimodal distribution having two peaks around 4.0 μm and 0.1 μm. Increasing temperature leads to the formation of more PM; varied oxygen content leads to much change of emitted PM. PM was also subjected to XRF analysis to quantify the elemental composition. The results show that PM of 0.1 μm is rich in sulfates. Meanwhile, SiO and AlO are prevalent in PM of 4.0 μm, which means that the last peak around 4.0 μm is mainly aluminosilicate salts.

关键词: prevalent     Combustion     cut-off diameter     temperature     particle    

A pre-compensation method of the systematic contouring error for repetitive command paths

D. L. ZHANG,Y. H. CHEN,Y. P. CHEN

《机械工程前沿(英文)》 2015年 第10卷 第4期   页码 367-372 doi: 10.1007/s11465-015-0367-5

摘要:

For a repetitive command path, pre-compensating the contouring error by modifying the command path is practical. To obtain the pre-compensation value with better accuracy, this paper proposes the use of a back propagation neural network to extract the function of systematic contouring errors. Furthermore, by using the extracted function, the contouring error can be easily pre-compensated. The experiment results verify that the proposed compensation method can effectively reduce contouring errors.

关键词: contouring error     pre-compensation     motion control system     back propagation (BP) neural network    

Experimental and parametrical investigation of pre-stressed ultrahigh-performance fiber-reinforced concrete

《结构与土木工程前沿(英文)》 2023年 第17卷 第3期   页码 411-428 doi: 10.1007/s11709-023-0928-3

摘要: In this study, ultrahigh-performance fiber-reinforced concrete (UHPFRC) used in a type B70 concrete sleeper is investigated experimentally and parametrically. The main parameters investigated are the steel fiber volume fractions (0%, 0.5%, 1%, and 1.5%). Under European standards, 35 UHPFRC sleepers are subjected to static bending tests at the center and rail seat sections, and the screw on the fastening system is pulled out. The first cracking load, failure load, failure mode, crack propagation, load–deflection curve, load–crack width, and failure load from these tests are measured and compared with those of a control sleeper manufactured using normal concrete C50. The accuracy of the parametric study is verified experimentally. Subsequently, the results of the study are applied to UHPFRC sleepers with different concrete volumes to investigate the effects of the properties of UHPFRC on their performance. Experimental and parametric study results show that the behavior of UHPFRC sleepers improves significantly when the amount of steel fiber in the mix is increased. Sleepers manufactured using UHPFRC with a steel fiber volume fraction of 1% and a concrete volume less than 25% that of standard sleeper B70 can be used under the same loads and requirements, which contributes positively to the cost and surrounding environment.

关键词: pre-stressed concrete sleeper     ultrahigh performance fiber-reinforced concrete     pull-out test     static bending test     steel fiber     aspect ratio     volume fraction    

Investigation into viability of using two-stage (pre-placed aggregate) concrete in Irish setting

John O’MALLEY, Hakim S. ABDELGADER,

《结构与土木工程前沿(英文)》 2010年 第4卷 第1期   页码 127-132 doi: 10.1007/s11709-010-0007-4

摘要: Two-stage (pre-placed aggregate) concrete (TSC) consists of coarse aggregate, which is first deposited into the formwork, and grout, which is later pumped into the formwork from the bottom up to bind the stone together into a monolith. During the course of this study the formation of grout for two stage concrete was investigated using readily available 5 mm sand mixed in a slow speed paddle mixer.  Silica fume and a superplasticizer were used in the mix to see if the necessary stability and fluidity could be achieved without the use of a specialized plant, essentially to see if TSC could be produced on a small scale using native Irish aggregates. A much higher degree of sedimentation was recorded during testing than was expected. As a result, the use of 5 mm sand and a slow speed mixer in combination were found to be not conducive to the successful production of TSC grout, without further research and testing.

关键词: grout     pre-placed     concrete     two-stage concrete (TSC)    

Optimization of denitrifying phosphorus removal in a pre-denitrification anaerobic/anoxic/post-aeration+ nitrification sequence batch reactor (pre-A

Weihua Zhao, Meixiang Wang, Jianwei Li, Yu Huang, Baikun Li, Cong Pan, Xiyao Li, Yongzhen Peng

《环境科学与工程前沿(英文)》 2018年 第12卷 第5期 doi: 10.1007/s11783-018-1084-1

摘要:

A novel two sludge pre-A2NSBR system was developed.

Advanced N and P removal was optimized to treat real domestic wastewater.

Nitrifiers and PAOs were enriched with 19.41% and 26.48%, respectively.

Acetate was demonstrated as the high-quality carbon source type.

关键词: Denitrifying phosphorus removal     C/N ratio     Nitrate recycling     Carbon source type     Biological nutrient removal     Pre-A2NSBR system    

标题 作者 时间 类型 操作

Techno-economic comparison of three technologies for pre-combustion CO

Simon Roussanaly, Monika Vitvarova, Rahul Anantharaman, David Berstad, Brede Hagen, Jana Jakobsen, Vaclav Novotny, Geir Skaugen

期刊论文

dioxide over porous solid adsorbents lithium silicate, lithium aluminate and magnesium aluminate at pre-combustion

P. V. Korake, A. G. Gaikwad

期刊论文

The capture of carbon dioxide by transition metal aluminates, calcium aluminate, calcium zirconate, calcium silicate and lithium zirconate

Ganesh TILEKAR, Kiran SHINDE, Kishor KALE, Reshma RASKAR, Abaji GAIKWAD

期刊论文

Influence of temperature on cam-tappet lubrication in an internal combustion engine

CHANG Qiuying, YANG Peiran, WANG Jing, CHEN Quanshi

期刊论文

Impact of oxygen enriched combustion on the performance of a single cylinder diesel engine

K. RAJKUMAR, P. GOVINDARAJAN

期刊论文

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

Xiaoguang LI, Lingyan ZENG, Hongye LIU, Yao LI, Yifu LI, Yunlong ZHAO, Bo JIAO, Minhang SONG, Shaofeng ZHANG, Zhichao CHEN, Zhengqi LI

期刊论文

Modification of premixed combustion in shear layers by grid turbulence

MU Kejin, WANG Yue, ZHANG Zhedian, NIE Chaoqun

期刊论文

Numerical simulation of combustion characteristics at different coal concentrations in bituminous coal

Chunlong LIU, Qunyi ZHU, Zhengqi LI, Qiudong ZONG, Yiquan XIE, Lingyan ZENG

期刊论文

Numerical simulation of bituminous coal combustion in a full-scale tiny-oil ignition burner: influence

Zhengqi LI, Chunlong LIU, Xiang ZHANG, Lingyan ZENG, Zhichao CHEN

期刊论文

Nonlinear analysis of pre-tensioned glass wall facade by stability function with initial imperfection

Siu-Lai CHAN, Yaopeng LIU, Andy LEE,

期刊论文

Influence of mineral transformation on emission of particulate matters during coal combustion

LIU Xiaowei, XU Minghou, YU Dunxi, GAO Xiangpeng, CAO Qian, HAO Wei

期刊论文

A pre-compensation method of the systematic contouring error for repetitive command paths

D. L. ZHANG,Y. H. CHEN,Y. P. CHEN

期刊论文

Experimental and parametrical investigation of pre-stressed ultrahigh-performance fiber-reinforced concrete

期刊论文

Investigation into viability of using two-stage (pre-placed aggregate) concrete in Irish setting

John O’MALLEY, Hakim S. ABDELGADER,

期刊论文

Optimization of denitrifying phosphorus removal in a pre-denitrification anaerobic/anoxic/post-aeration+ nitrification sequence batch reactor (pre-A

Weihua Zhao, Meixiang Wang, Jianwei Li, Yu Huang, Baikun Li, Cong Pan, Xiyao Li, Yongzhen Peng

期刊论文