资源类型

期刊论文 183

年份

2024 1

2023 14

2022 17

2021 12

2020 10

2019 18

2018 7

2017 19

2016 8

2015 7

2014 5

2013 4

2012 6

2011 5

2010 7

2009 11

2008 10

2007 10

2006 3

2003 1

展开 ︾

关键词

内燃机 2

柴油机 2

ANSYS/LS-DYNA 1

HBV相关疾病 1

IgG抗体 1

Nd-YAG 1

Nrf2/Keap1 系统 1

PET酶 1

PET降解 1

Pd局域环境 1

RE-Si3N4 1

Si/Al 比值 1

Tempotron;神经元模型;感受野;高斯差分;图像翻转;图像旋转 1

Vidar相机 1

YAG激光淬火 1

n-Si 1

个人热管理 1

中深孔台阶爆破 1

举国体制模式 1

展开 ︾

检索范围:

排序: 展示方式:

Combustion characteristics of SI engine fueled with methanol-gasoline blends during cold start

SONG Ruizhi, LIU Shenghua, LIANG Xiaoqiang, Tiegang H U

《能源前沿(英文)》 2008年 第2卷 第4期   页码 395-400 doi: 10.1007/s11708-008-0081-7

摘要: A 3-cylinder port fuel injection (PFI) engine fueled with methanol-gasoline blends was used to study combustion and emission characteristics. Cylinder pressure analysis indicates that engine combustion is improved when methanol is added to gasoline. With the increase of methanol, the flame developing period and the rapid combustion period are shortened, and the indicated mean effective pressure increases during the first 50 cycles. Meanwhile, a novel quasi-instantaneous sampling system was designed to measure engine emissions during cold start and warm-up. The results at 5°C show that unburned hydrocarbon (UHC) and carbon monoxide (CO) decrease remarkably. Hydrocarbon (HC) reduces by 40% and CO by 70% when fueled with M30 (30% methanol in volume). The exhaust gas temperature is about 140°C higher at 200 s after operation compared with that of gasoline.

关键词: combustion     3-cylinder     indicated     Cylinder pressure     emission    

Numerical simulation of charge stratifications to improve combustion and NO formation of lean-burn SI

Zhijun PENG ,

《能源前沿(英文)》 2009年 第3卷 第3期   页码 353-358 doi: 10.1007/s11708-009-0035-8

摘要: The influences of charge stratification on spark ignition (SI) engine combustion and NO emission were analyzed using a phenomenological model. The mixture in the cylinder was divided spherically into three parts: a central core with a stoichiometric air-fuel charge, a dilution region without any combustible charge, and a mixing region lying between the core and the dilution region. Three mixture stratification parameters such as the extent of dilution in the mixing region, the extent of combustible charge in the mixing region, and the gradient of stratification in the mixing region were investigated. The results indicate that the extent of combustible charge in the mixing region could reduce in-cylinder NO formation significantly, compared with the extent of dilution in the mixing region. As long as the degree of dilution in the mixing region is within the dilution limit of the combustible charge, the gradient of dilution has little effect on combustion and NO formation.

关键词: charge stratification     SI engine     lean-burn combustion     NO emission    

Plasma enhanced chemical vapor deposition of excellent a-Si:H passivation layers for a-Si:H/c-Si heterojunction

Lei ZHAO,Wenbin ZHANG,Jingwei CHEN,Hongwei DIAO,Qi WANG,Wenjing WANG

《能源前沿(英文)》 2017年 第11卷 第1期   页码 85-91 doi: 10.1007/s11708-016-0437-3

摘要: The intrinsic a-Si:H passivation layer inserted between the doped a-Si:H layer and the c-Si substrate is very crucial for improving the performance of the a-Si:H/c-Si heterojunction (SHJ) solar cell. The passivation performance of the a-Si:H layer is strongly dependent on its microstructure. Usually, the compact a-Si:H deposited near the transition from the amorphous phase to the nanocrystalline phase by plasma enhanced chemical vapor deposition (PECVD) can provide excellent passivation. However, at the low deposition pressure and low deposition power, such an a-Si:H layer can be only prepared in a narrow region. The deposition condition must be controlled very carefully. In this paper, intrinsic a-Si:H layers were prepared on n-type Cz c-Si substrates by 27.12 MHz PECVD at a high deposition pressure and high deposition power. The corresponding passivation performance on c-Si was investigated by minority carrier lifetime measurement. It was found that an excellent a-Si:H passivation layer could be obtained in a very wide deposition pressure and power region. Such wide process window would be very beneficial for improving the uniformity and the yield for the solar cell fabrication. The a-Si:H layer microstructure was further investigated by Raman and Fourier transform infrared (FTIR) spectroscopy characterization. The correlation between the microstructure and the passivation performance was revealed. According to the above findings, the a-Si:H passivation performance was optimized more elaborately. Finally, a large-area SHJ solar cell with an efficiency of 22.25% was fabricated on the commercial 156 mm pseudo-square n-type Cz c-Si substrate with the open-circuit voltage ( ) of up to 0.732 V.

关键词: PECVD     high pressure and high power     a-Si:H microstructure     passivation     heterojunction solar cell    

Design and modeling of a free-piston engine generator

《能源前沿(英文)》   页码 811-821 doi: 10.1007/s11708-022-0848-2

摘要: Free-piston engine generators (FPEGs) can be applied as decarbonized range extenders for electric vehicles because of their high thermal efficiency, low friction loss, and ultimate fuel flexibility. In this paper, a parameter-decoupling approach is proposed to model the design of an FPEG. The parameter-decoupling approach first divides the FPEG into three parts: a two-stroke engine, an integrated scavenging pump, and a linear permanent magnet synchronous machine (LPMSM). Then, each of these is designed according to predefined specifications and performance targets. Using this decoupling approach, a numerical model of the FPEG, including the three aforementioned parts, was developed. Empirical equations were adopted to design the engine and scavenging pump, while special considerations were applied for the LPMSM. A finite element model with a multi-objective genetic algorithm was adopted for its design. The finite element model results were fed back to the numerical model to update the LPMSM with increased fidelity. The designed FPEG produced 10.2 kW of electric power with an overall system efficiency of 38.5% in a stable manner. The model provides a solid foundation for the manufacturing of related FPEG prototypes.

关键词: free-piston engine generator     linear permanent magnet synchronous machine     system design     numerical model     finite element method    

Analysis of the double-layer α-Si:H emitter with different doping concentrations for α-Si:H/c-Si heterojunction

Haibin HUANG,Gangyu TIAN,Tao WANG,Chao GAO,Jiren YUAN,Zhihao YUE,Lang ZHOU

《能源前沿(英文)》 2017年 第11卷 第1期   页码 92-95 doi: 10.1007/s11708-016-0432-8

摘要: Double-layer emitters with different doping concentrations (DLE) have been designed and prepared for amorphous silicon/crystalline silicon (α-Si:H/c-Si) heterojunction solar cells. Compared with the traditional single layer emitter, both the experiment and the simulation (AFORS-HET, http://www.paper.edu.cn/html/releasepaper/2014/04/282/) prove that the double-layer emitter increases the short circuit current of the cells significantly. Based on the quantum efficiency (QE) results and the current-voltage-temperature analysis, the mechanism for the experimental results above has been investigated. The possible reasons for the increased current include the enhancement of the QE in the short wavelength range, the increase of the tunneling probability of the current transport and the decrease of the activation energy of the emitter layers.

关键词: double-layer emitter     α-Si:H/c-Si heterojunction solar cell     short circuit current     quantum efficiency     current-voltage-temperature    

Study of engine performance, emission and combustion characteristics fueled with diesel-like fuel producedfrom waste engine oil and waste plastics

V. Edwin Geo, Ankit Sonthalia, Fethi Aloui, Femilda Josephin J. S.

《环境科学与工程前沿(英文)》 2018年 第12卷 第4期 doi: 10.1007/s11783-018-1063-6

摘要:

To derive liquid fuel from waste engine oil and plastics thorough pyrolysis process

To make equal blend of waste engine oil and plastics with diesel fuel

To find the suitability of fuel from waste in diesel engine through performance, emission and combustion characteristics

关键词: Waste engine oil     Waste plastic oil     Diesel fuel     Pyrolysis     Compression ignition engine    

Stability and dynamics of rotor system with 45° slant crack on shaft

Yanli LIN, Xiaohui SI, Fulei CHU

《机械工程前沿(英文)》 2011年 第6卷 第2期   页码 203-213 doi: 10.1007/s11465-011-0131-4

摘要:

Crack on a shaft is one of the common damages in a rotor system. In this paper, transverse vibrations are calculated to compare the influences of transverse crack and slant crack on the rotor system. Results show that the vibration amplitude of the rotor system with a 45° slant crack on the shaft is larger than that with a transverse crack when the two types of crack have the same depth and the rotor system runs in the same condition. Stability and dynamic characteristics of the rotor system with a 45° slant crack on the shaft under torsional excitation are analyzed by considering opening and closing of the crack. It is shown that the instability of the transverse vibration of the rotor system increases with increasing difference between the bending stiffness in two main directions, and the vibration is stable when the two bending stiffness are identical. The spectrum analysis of the steady-state response reveals that the gravity and the eccentricity produce different frequency components, and when the two bending stiffness are identical, the multiple frequency components of the torsional excitation disappear. Further investigation shows that the vibration amplitudes in combined frequencies increase rapidly in transversal, torsional, and axial vibration with increasing slant crack depth. The results are helpful for the understanding the dynamic behavior of a rotor system with a slant crack on a shaft and can be used for the detection of the slant crack on a shaft.

关键词: rotor dynamics     slant crack     stability     torsional excitation     open and close    

A new miniaturized engine based on thermomagnetic effect of magnetic fluids

Lujun ZHOU, Yimin XUAN, Qiang LI, Wenlei LIAN

《能源前沿(英文)》 2009年 第3卷 第2期   页码 160-166 doi: 10.1007/s11708-009-0018-9

摘要: A new engine system, essentially consisting of a permanent NdFeB magnet, a kerosene-based magnetic fluid and a rotor, is proposed based on the thermomagnetic effect of a temperature-sensitive magnetic fluid. The rotor was driven by the thermal convection of the magnetic fluid in the presence of a homogeneous external magnetic field. A digital camera was used to record the rotation speed of the rotor to investigate the performance of the engine system under varying conditions such as heat load, heat sink temperature, and magnetic field distribution. The peak angle velocity obtained for the rotor was about 2.1 rad/min. The results illustrate that the rotation speed of the rotor increases as the input heat load increases, or as the heat sink temperature decreases. The performance of the motor is considerably influenced by the magnetic field imposed. Therefore, the performance of such an engine can be controlled conveniently by changing the external magnetic field and/or the temperature distribution in the fluid.

关键词: magnetic fluid     thermomagnetic effect     engine    

Full-field dynamic strain reconstruction of an aero-engine blade from limited displacement responses

《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0731-1

摘要: Blade strain distribution and its change with time are crucial for reliability analysis and residual life evaluation in blade vibration tests. Traditional strain measurements are achieved by strain gauges (SGs) in a contact manner at discrete positions on the blades. This study proposes a method of full-field and real-time strain reconstruction of an aero-engine blade based on limited displacement responses. Limited optical measured displacement responses are utilized to reconstruct the full-field strain. The full-field strain distribution is in-time visualized. A displacement-to-strain transformation matrix is derived on the basis of the blade mode shapes in the modal coordinate. The proposed method is validated on an aero-engine blade in numerical and experimental cases. Three discrete vibrational displacement responses measured by laser triangulation sensors are used to reconstruct the full-field strain over the whole operating time. The reconstructed strain responses are compared with the results measured by SGs and numerical simulation. The high consistency between the reconstructed and measured results demonstrates the accurate strain reconstructed by the method. This paper provides a low-cost, real-time, and visualized measurement of blade full-field dynamic strain using displacement response, where the traditional SGs would fail.

关键词: aero-engine blade     displacement response     dynamic strain reconstruction     mode shape     strain gauge    

Satellite scheduling engine: The intelligent solver for future multi-satellite management

《工程管理前沿(英文)》 2022年 第9卷 第4期   页码 683-688 doi: 10.1007/s42524-022-0222-4

Group-based multiple pipe routing method for aero-engine focusing on parallel layout

《机械工程前沿(英文)》 2021年 第16卷 第4期   页码 798-813 doi: 10.1007/s11465-021-0645-3

摘要: External pipe routing for aero-engine in limited three-dimensional space is a typical nondeterministic polynomial hard problem, where the parallel layout of pipes plays an important role in improving the utilization of layout space, facilitating pipe assembly, and maintenance. This paper presents an automatic multiple pipe routing method for aero-engine that focuses on parallel layout. The compressed visibility graph construction algorithm is proposed first to determine rapidly the rough path and interference relationship of the pipes to be routed. Based on these rough paths, the information of pipe grouping and sequencing are obtained according to the difference degree and interference degree, respectively. Subsequently, a coevolutionary improved differential evolution algorithm, which adopts the coevolutionary strategy, is used to solve multiple pipe layout optimization problem. By using this algorithm, pipes in the same group share the layout space information with one another, and the optimal layout solution of pipes in this group can be obtained in the same evolutionary progress. Furthermore, to eliminate the minor angle deviation of parallel pipes that would cause assembly stress in actual assembly, an accurate parallelization processing method based on the simulated annealing algorithm is proposed. Finally, the simulation results on an aero-engine demonstrate the feasibility and effectiveness of the proposed method.

关键词: multiple pipe routing     optimization algorithm     aero-engine     pipe grouping     parallel layout    

Mercury enrichment in

Chunhao Dai, Pufeng Qin, Zhangwei Wang, Jian Chen, Xianshan Zhang, Si Luo

《环境科学与工程前沿(英文)》 2017年 第11卷 第1期 doi: 10.1007/s11783-017-0892-z

摘要: Mercury enrichment in response to elevated atmospheric mercury concentrations in the organs of rape ( ) was investigated. Elevated soil mercury content had significant impact on mercury accumulation in rape stems, roots, seeds and seed coats. Leaf mercury in the leaves was mostly affected by atmospheric input while the stems were mostly affected by soil concentrations. Mercury in the aboveground plant tissue mainly derived from atmospheric absorption, and atmospheric mercury absorption in leaves was higher than that in the stems. Mercury enrichment in response to elevated atmospheric mercury concentrations in the organs of rape ( ) was investigated using an open top chamber fumigation experiment and a soil mercury enriched cultivation experiment. Results indicate that the mercury concentration in leaves and stems showed a significant variation under different concentrations of mercury in atmospheric and soil experiments while the concentration of mercury in roots, seeds and seed coats showed no significant variation under different atmospheric mercury concentrations. Using the function relation established by the experiment, results for atmospheric mercury sources in rape field biomass showed that atmospheric sources accounted for at least 81.81% of mercury in rape leaves and 32.29% of mercury in the stems. Therefore, mercury in the aboveground biomass predominantly derives from the absorption of atmospheric mercury.

关键词: Open top chamber     Gaseous elemental mercury (GEM)     Soil Mercury     Brassica napus    

Laser ablation of block copolymers with hydrogen-bonded azobenzene derivatives

Jintang Huang, Youju Huang, Si Wu

《化学科学与工程前沿(英文)》 2018年 第12卷 第3期   页码 450-456 doi: 10.1007/s11705-018-1735-6

摘要:

Supramolecular assemblies (PS-b-P4VP(AzoR)) are fabricated by hydrogen-bonding azobenzene derivatives (AzoR) to poly(4-vinyl pyridine) blocks of polystyrene-block-poly(4-vinyl pyridine) (PS-b-P4VP). PS-b-P4VP(AzoR) forms phase separated nanostructures with a period of ~75–105 nm. A second length scale structure with a period of 2 µm is fabricated on phase separated PS-b-P4VP(AzoR) by laser interference ablation. Both the concentration and the substituent of AzoR in PS-b-P4VP(AzoR) affect the laser ablation process. The laser ablation threshold of PS-b-P4VP(AzoR) decreases as the concentration of AzoR increases. In PS-b-P4VP(AzoR) with different substituents (R= CN, H, and CH3), ablation thresholds follow the trend: PS-b-P4VP(AzoCN)<PS-b-P4VP(AzoCH3)<PS-b-P4VP(AzoH). This result indicates that the electron donor group (CH3) and the electron acceptor group (CN) can lower the ablation threshold of PS-b-P4VP(AzoR).

关键词: laser ablation     block copolymers     hydrogen-bond     azobenzene derivatives     supramolecular assembly    

Progress in hydrogen enriched hydrocarbons combustion and engine applications

Zuohua HUANG, Jinhua WANG, Erjiang HU, Chenglong TANG, Yingjia ZHANG

《能源前沿(英文)》 2014年 第8卷 第1期   页码 73-80 doi: 10.1007/s11708-013-0287-1

摘要: The paper summarized the work on hydrogen enriched hydrocarbons combustion and its application in engines. The progress and understanding on laminar burning velocity, flame instability, flame structure flame and chemical kinetics were presented. Based on fundamental combustion, both homogeneous spark-ignition engine and direct-injection spark-ignition engine fueled with natural gas-hydrogen blends were conducted and the technical route of natural gas-hydrogen combined with exhaust gas recirculation was proposed which experimentally demonstrated benefits on both thermal efficiency improvement and emissions reduction.

关键词: hydrogen enriched hydrocarbon combustion     fundamental study     engine application    

Typical off-design analytical performances of internal combustion engine cogeneration

Xiaohong HE, Ruixian CAI

《能源前沿(英文)》 2009年 第3卷 第2期   页码 184-192 doi: 10.1007/s11708-009-0007-z

摘要: Based on experimental data, typical off-design characteristic curves with corresponding formulas of internal combustion engine (ICE) are summarized and investigated. In combination with analytical solution of single-pressure heat recovery steam generator (HRSG) and influence of ambient pressure on combined heat and power (CHP) system, off-design operation regularities of ICE cogeneration are analyzed. The approach temperature difference Δ , relative steam production and superheated steam temperature decrease with the decrease in engine load. The total energy efficiency, equivalent exergy efficiency and economic exergy efficiency first increase and then decrease. Therefore, there exists an optimum value, corresponding to ICE best efficiency operating condition. It is worth emphasizing that Δ is likely to be negative in low load condition with high design steam parameter and low ICE design exhaust gas temperature. Compared with single shaft gas turbine cogeneration, Δ in ICE cogeneration is more likely to be negative. The main reason for this is that the gas turbine has an increased exhaust gas flow with the decrease in load; while ICE is on the contrary. Moreover, ICE power output and efficiency decrease with the decrease in ambient pressure. Hence, approach temperature difference, relative steam production and superheated steam temperature decrease rapidly while the cogeneration efficiencies decrease slightly. It is necessary to consider the influence of ambient conditions, especially the optimization of ICE performances at different places, on cogeneration performances.

关键词: internal combustion engine (ICE)     cogeneration     heat recovery steam generator (HRSG)     off-design     superheated steam     saturated steam     ambient pressure    

标题 作者 时间 类型 操作

Combustion characteristics of SI engine fueled with methanol-gasoline blends during cold start

SONG Ruizhi, LIU Shenghua, LIANG Xiaoqiang, Tiegang H U

期刊论文

Numerical simulation of charge stratifications to improve combustion and NO formation of lean-burn SI

Zhijun PENG ,

期刊论文

Plasma enhanced chemical vapor deposition of excellent a-Si:H passivation layers for a-Si:H/c-Si heterojunction

Lei ZHAO,Wenbin ZHANG,Jingwei CHEN,Hongwei DIAO,Qi WANG,Wenjing WANG

期刊论文

Design and modeling of a free-piston engine generator

期刊论文

Analysis of the double-layer α-Si:H emitter with different doping concentrations for α-Si:H/c-Si heterojunction

Haibin HUANG,Gangyu TIAN,Tao WANG,Chao GAO,Jiren YUAN,Zhihao YUE,Lang ZHOU

期刊论文

Study of engine performance, emission and combustion characteristics fueled with diesel-like fuel producedfrom waste engine oil and waste plastics

V. Edwin Geo, Ankit Sonthalia, Fethi Aloui, Femilda Josephin J. S.

期刊论文

Stability and dynamics of rotor system with 45° slant crack on shaft

Yanli LIN, Xiaohui SI, Fulei CHU

期刊论文

A new miniaturized engine based on thermomagnetic effect of magnetic fluids

Lujun ZHOU, Yimin XUAN, Qiang LI, Wenlei LIAN

期刊论文

Full-field dynamic strain reconstruction of an aero-engine blade from limited displacement responses

期刊论文

Satellite scheduling engine: The intelligent solver for future multi-satellite management

期刊论文

Group-based multiple pipe routing method for aero-engine focusing on parallel layout

期刊论文

Mercury enrichment in

Chunhao Dai, Pufeng Qin, Zhangwei Wang, Jian Chen, Xianshan Zhang, Si Luo

期刊论文

Laser ablation of block copolymers with hydrogen-bonded azobenzene derivatives

Jintang Huang, Youju Huang, Si Wu

期刊论文

Progress in hydrogen enriched hydrocarbons combustion and engine applications

Zuohua HUANG, Jinhua WANG, Erjiang HU, Chenglong TANG, Yingjia ZHANG

期刊论文

Typical off-design analytical performances of internal combustion engine cogeneration

Xiaohong HE, Ruixian CAI

期刊论文