资源类型

期刊论文 26

年份

2023 1

2022 1

2021 2

2020 2

2019 1

2018 1

2016 1

2015 4

2014 3

2010 5

2009 1

2007 3

2006 1

展开 ︾

关键词

人工岛 1

侧向入口 1

入口总压 1

全连接神经网络 1

压降 1

压降特性;均相模型;分相模型;微通道;流动沸腾 1

喷墨打印 1

复合薄膜 1

大直径钢圆筒 1

恒定流 1

按需滴化微喷射生物打印 1

振动沉桩 1

旋风分离器 1

木材表面 1

水击 1

波动方程分析 1

海洋基础 1

港珠澳大桥 1

滴涂法 1

展开 ︾

检索范围:

排序: 展示方式:

Experimental studies on the axial crash behavior of aluminum foam-filled hat sections

WANG Qing-chun, FAN Zi-jie, GUI Liang-jin, WANG Zheng-hong, FU Zi-lai

《机械工程前沿(英文)》 2006年 第1卷 第4期   页码 381-387 doi: 10.1007/s11465-006-0044-9

摘要: Drop hammer tests were carried out to study the axial crash behavior of aluminum foam-filled hat sections. First, the axial crash tests of the empty hat sections, aluminum foam and the aluminum foam-filled hat sections were carried out; then, based upon the test results, the axial crash behavior of the aluminum foam-filled hat sections were analyzed. It was found that aluminum foam filling can increase the energy absorption capacities of the hat sections. Compared with the non-filled structures, aluminum foamfilled structures were much more stable and needed less mass to absorb the specified energy.

关键词: specified energy     aluminum foam-filled     energy absorption     non-filled     Drop hammer    

Evaluation of strategies for the subsequent use of CO 2

Marc SCHAEFER, Frank BEHRENDT, Thomas HAMMER,

《化学科学与工程前沿(英文)》 2010年 第4卷 第2期   页码 172-183 doi: 10.1007/s11705-009-0236-z

摘要: If substantial amounts of CO, which according to actual scenarios may in the future be captured from industrial processes and power generation, shall be utilized effectively, scalable energy efficient technologies will be required. Thus, a survey was performed to assess a large variety of applications utilizing CO chemically (e.g., production of synthesis-gas, methanol synthesis), biologically (e.g., CO as fertilizer in green houses, production of algae), or physically (enhancement of fossil fuel recovery, use as refrigerant). For each of the processes, material and energy balances were set up. Starting with pure CO at standard conditions, expenditure for transport and further process specific treatment were included. Based on these calculations, the avoidance of greenhouse gas emissions by applying the discussed technologies was evaluated. Based on the currently available technologies, applications for enhanced fossil fuel recovery turn out to be most attractive regarding the potential of utilizing large quantities of CO (total capacity>1000 Gt CO) and producing significant amounts of marketable products on one hand and having good energy and material balances on the other hand (

关键词: industrial     generation     production     substantial     enhancement    

CFD evaluation of pressure drop across a 3-D filter housing for industrial gas turbine plants

Fidelis I. ABAM,Samuel O. EFFIOM,Olayinka S. OHUNAKIN

《能源前沿(英文)》 2016年 第10卷 第2期   页码 192-202 doi: 10.1007/s11708-016-0406-x

摘要: This paper investigated the flow distribution and total pressure drop across a designed 3-D filter housing integrated with a 3-stage filtration system using computational fluid dynamics (CFD). The filter housing model was proposed for a heavy-duty industrial gas turbine plant operating at an average ambient temperature of 20°C.The pressure drops across the classes of filters were 652.8 Pa, 2692.2 Pa, 887.8 Pa, 776.2 Pa and 2304.2 Pa for I-GB, GB-GA, GA-FA, FA-HA, and HA-O, respectively. The results obtained indicated an acceptable total pressure drop of 7.2% for the entire filter housing before filter clean-up. Although the CFD simulation result shows that small outlet flow velocity and transonic flows exist at the outlet of the filter housing, the designed filter housing was proved compatible with the studied GT, for inlet flow conditions between 600≤ ≤610 kg/s and 60≤ ≤70 m/s for the air flow rate and velocity, respectively. Furthermore, the designed filter housing could be adopted for the studied GT and locations of Usan and Maiduguri in Nigeria, and other locations with similar environmental conditions.

关键词: computational fluid dynamics (CFD)     pressure drop     flow distribution     filter housing     gas turbine    

A biofilter model for simultaneous simulation of toluene removal and bed pressure drop under varied inlet

Jinying XI,Insun KANG,Hongying HU,Xian ZHANG

《环境科学与工程前沿(英文)》 2015年 第9卷 第3期   页码 554-562 doi: 10.1007/s11783-014-0671-z

摘要: In this study, a biofiltration model including the effect of biomass accumulation and inert biomass growth is developed to simultaneously predict the Volatile Organic Compounds (VOCs) removal and filter bed pressure drop under varied inlet loadings. A laboratory-scale experimental biofilter for gaseous toluene removal was set up and operated for 100 days with inlet toluene concentration ranging from 250 to 2500 mg?m . According to sensitivity analysis based on the model, the VOCs removal efficiency of the biofilter is more sensitive to Henry’s constant, the specific surface area of the filter bed and the thickness of water layer, while the filter bed pressure drop is more sensitive to biomass yield coefficient and original void fraction. The calculated toluene removal efficiency and bed pressure drop satisfactorily fit the experimental data under varied inlet toluene loadings, which indicates the model in this study can be used to predict VOCs removal and bed pressure drop simultaneously. Based on the model, the effect of mass-transfer parameters on VOCs removal and the stable-run time of a biofilter are analyzed. The results demonstrate that the model can function as a good tool to evaluate the effect of biomass accumulation and optimize the design and operation of biofilters.

关键词: Volatile Organic Compounds (VOCs)     biofilters     modelling     biomass accumulation     pressure drop    

Ultrasound-assisted emulsification solidified floating organic drop microextraction for the determination

Qingyun CHANG, Jingwen ZHANG, Xin DU, Jingjun MA, Jingci LI,

《环境科学与工程前沿(英文)》 2010年 第4卷 第2期   页码 187-195 doi: 10.1007/s11783-010-0030-7

摘要: A simple and efficient liquid-phase microextraction (LPME) technique was developed using ultrasound-assisted emulsification solidified floating organic drop microextraction (USAE-SFODME) combined with flame atomic absorption spectrometry, for the extraction and determination of trace copper in water samples. 1-(2-Pyridylazo)-2-naphthol (PAN) was used as chelating agent. Microextraction efficiency factors (including extraction solvent type, extraction volume, time, temperature, and pH), the amount of the chelating agent, and salt effect were investigated and optimized. Under the optimum extraction conditions, figures of merit of the proposed method were evaluated. The calibration graph was linear in the range of 20–600 g·L with a detection limit of 0.76 g·L. The relative standard deviation (R.S.D) for ten replicate measurements of 20 and 400 g·L of copper was 3.83% and 2.65%, respectively. Finally, the proposed method was applied to tap water, river water, and sea water, and accuracy was assessed through the analysis of certified reference water or recovery experiments.

关键词: ultrasound-assisted emulsification     solidified floating organic drop microextraction     flame atomic absorption spectrometry     preconcentration     copper    

Hybrid intelligent water drop bundled wavelet neural network to solve the islanding detection by inverter-based

Mehrdad TARAFDAR HAGH,Homayoun EBRAHIMIAN,Noradin GHADIMI

《能源前沿(英文)》 2015年 第9卷 第1期   页码 75-90 doi: 10.1007/s11708-014-0337-3

摘要: In this paper, a passive neuro-wavelet based islanding detection technique for grid-connected inverter-based distributed generation was developed. The weight parameters of the neural network were optimized by intelligent water drop (IWD) to improve the capability of the proposed technique in the proposed problem. The proposed method utilizes and combines wavelet analysis and artificial neural network (ANN) to detect islanding. Connecting distributed generator to the distribution network has many benefits such as increasing the capacity of the grid and enhancing the power quality. However, it gives rise to many problems. This is mainly due to the fact that distribution networks are designed without any generation units at that level. Hence, integrating distributed generators into the existing distribution network is not problem-free. Unintentional islanding is one of the encountered problems. Discrete wavelet transform (DWT) is capable of decomposing the signals into different frequency bands. It can be utilized in extracting discriminative features from the acquired voltage signals. In passive schemes with a large non-detection zone (NDZ), concern has been raised on active method due to its degrading power quality effect. The main emphasis of the proposed scheme is to reduce the NDZ to as close as possible and to keep the output power quality unchanged. The simulation results from Matlab/Simulink shows that the proposed method has a small non-detection zone, and is capable of detecting islanding accurately within the minimum standard time.

关键词: islanding detection     neuro-wavelet     intelligent water drop (IWD)     non-detection zone (NDZ)     distributed generation (DG)    

The investigation of pressure drop in moving-beds

CHEN Yunhua, ZHU Xuedong, WU Yongqiang, ZHU Zibin

《化学科学与工程前沿(英文)》 2007年 第1卷 第2期   页码 184-189 doi: 10.1007/s11705-007-0034-4

摘要: The pressure drop of a cross-flow moving-bed was investigated in a two-dimensional rectangular apparatus. The effects of the particle velocity, the superficial gas velocity, the formation and development of cavity/raceway and voidage of particles on the pressure drop were investigated experimentally under the operational conditions of 0.09 1.35 m/s of the superficial gas velocity and 0.95 9.68 cm/min of the particle velocity. The experimental results show that the particle velocity has little influence on the pressure drop, while the phenomena of cavity and pinning occur when the cross-flow velocity is high enough. The development of a cavity or a raceway can result in three types of variations of pressure drop with time: stabilization, slight fluctuation and severe fluctuation. A cavity appears in a process cycle of formation-growing up-collapsing-fluidization at a high gas velocity. On the basis of experimental results, a model for calculating the pressure drop after a cavity occurs and a dimensionless relationship of cavity size is developed, which gives a good qualitative account of the experimental data.

关键词: development     cross-flow velocity     superficial     qualitative account     stabilization    

产品跌落冲击耐撞性能稳健设计研究进展

杨书仪,刘德顺,赵继云,文泽军

《中国工程科学》 2010年 第12卷 第1期   页码 61-66

摘要:

跌落冲击是物体在短时间内受到强大冲击力而运动状态发生急剧变化的现象,是导致产品特别是小型机电产品外表破损、功能失效的主要原因。近年来,国内外研究学者针对如何提高产品抗跌落冲击的本质耐撞性能进行了大量研究。笔者从研究对象、研究方法等角度,系统总结了产品跌落冲击耐撞性和产品耐撞性能稳健设计的研究现状,归纳了有待进一步研究的问题。

关键词: 跌落冲击     耐撞性     稳健设计    

Pressure drop analysis on the positive half-cell of a cerium redox flow battery using computational fluid

Fernando F. Rivera, Berenice Miranda-Alcántara, Germán Orozco, Carlos Ponce de León, Luis F. Arenas

《化学科学与工程前沿(英文)》 2021年 第15卷 第2期   页码 399-409 doi: 10.1007/s11705-020-1934-9

摘要: Description of electrolyte fluid dynamics in the electrode compartments by mathematical models can be a powerful tool in the development of redox flow batteries (RFBs) and other electrochemical reactors. In order to determine their predictive capability, turbulent Reynolds-averaged Navier-Stokes (RANS) and free flow plus porous media (Brinkman) models were applied to compute local fluid velocities taking place in a rectangular channel electrochemical flow cell used as the positive half-cell of a cerium-based RFB for laboratory studies. Two different platinized titanium electrodes were considered, a plate plus a turbulence promoter and an expanded metal mesh. Calculated pressure drop was validated against experimental data obtained with typical cerium electrolytes. It was found that the pressure drop values were better described by the RANS approach, whereas the validity of Brinkman equations was strongly dependent on porosity and permeability values of the porous media.

关键词: CFD simulation     porous media     porous electrode     pressure drop     redox flow battery    

低高宽比矩形微通道中流动沸腾的压降特性

张炳雷,徐进良,肖泽军

《中国工程科学》 2007年 第9卷 第12期   页码 86-93

摘要: 以甲醇为工质,在不同进口温度、质量流率、热流密度和倾角下,对低高宽比矩形微通道中流动沸腾压降特性进行了研究,并分别采用均相模型和分相模型对通道压降进行了计算。通过对比实验结果与计算结果发现,均相模型中两相平均粘度的计算应当采用Dukler公式,用其他计算式时误差较大;利用LockhartMartinelli关系式进行的分相模型计算发现,现有C值计算公式,如Chisholm,Lee and Lee,Mishima及Qu and Mudawar等,都不能用于预测该实验中低高宽比微通道的两相压降。实验发现当通

关键词: 压降特性;均相模型;分相模型;微通道;流动沸腾    

metaheuristic optimizations (SCE and ABC) for prediction of compressive strength of concrete using rebound hammer

Dung Quang VU; Fazal E. JALAL; Mudassir IQBAL; Dam Duc NGUYEN; Duong Kien TRONG; Indra PRAKASH; Binh Thai PHAM

《结构与土木工程前沿(英文)》 2022年 第16卷 第8期   页码 1003-1016 doi: 10.1007/s11709-022-0846-9

摘要: In this study, we developed novel hybrid models namely Adaptive Neuro Fuzzy Inference System (ANFIS) optimized by Shuffled Complex Evolution (SCE) on the one hand and ANFIS with Artificial Bee Colony (ABC) on the other hand. These were used to predict compressive strength (Cs) of concrete relating to thirteen concrete-strength affecting parameters which are easy to determine in the laboratory. Field and laboratory tests data of 108 structural elements of 18 concrete bridges of the Ha Long-Van Don Expressway, Vietnam were considered. The dataset was randomly divided into a 70:30 ratio, for training (70%) and testing (30%) of the hybrid models. Performance of the developed fuzzy metaheuristic models was evaluated using standard statistical metrics: Correlation Coefficient (R), Root Mean Square Error (RMSE) and Mean Absolute Error (MAE). The results showed that both of the novel models depict close agreement between experimental and predicted results. However, the ANFIS-ABC model reflected better convergence of the results and better performance compared to that of ANFIS-SCE in the prediction of the concrete Cs. Thus, the ANFIS-ABC model can be used for the quick and accurate estimation of compressive strength of concrete based on easily determined parameters for the design of civil engineering structures including bridges.

关键词: shuffled complex evolution     artificial bee colony     ANFIS     concrete     compressive strength     Vietnam    

Numerical study of droplet dynamics impinging onto steel plate covered with scale layer

Jan BOHá?EK, Ale? HORáK

《机械工程前沿(英文)》 2010年 第5卷 第4期   页码 389-398 doi: 10.1007/s11465-010-0108-8

摘要: The steel hot rolling process is inseparably connected to an oxide layer called “scale” at high temperatures. Hydraulic descaling of rolled material is a part of all rolling trains. Surface quality after descaling is fundamental for the final surface quality of a rolled product. The process itself is not theoretically well described; various different approaches have been used to clarify the descaling problem. This paper describes the dynamics of high-speed impact between the compressible water droplet and the steel scale layer. The phenomenon is known as water hammer effect. The purpose of this study is to numerically verify the fact that impact stress can be a significant factor during the descaling process. Considering a high droplet impact speed (100–300 ms ), inferential extremely short time interval (0.1–5 μs) peaks in impact pressure reaching 300 MPa can be found. Droplet dynamics was simulated with the help of LS-Dyna solver, whereas the stress analysis was performed in ANSYS interface. The extreme pressure peaks of very short duration in an impact area are a new phenomenon in the descaling theory.

关键词: hydraulic descaling     scale     rolling     water-hammer     descaling theory    

Heat transfer and fluid flow analysis of an artificially roughened solar air heater: a CFD based investigation

Anil Singh YADAV,J. L. BHAGORIA

《能源前沿(英文)》 2014年 第8卷 第2期   页码 201-211 doi: 10.1007/s11708-014-0297-7

摘要: In this paper, the effect of rib (circular sectioned) spacing on average Nusselt number and friction factor in an artificially roughened solar air heater (duct aspect ratio, AR= 5:1) is studied by adopting the computational fluid dynamics (CFD) approach. Numerical solutions are obtained using commercial software ANSYS FLUENT v12.1. The computations based on the finite volume method with the semi-implicit method for pressure-linked equations (SIMPLE) algorithm have been conducted. Circular sectioned transverse ribs are applied at the underside of the top of the duct, i.e., on the absorber plate. The rib-height-to-hydraulic diameter ratio ( ) is 0.042. The rib-pitch-to-rib-height ( ) ratios studied are 7.14, 10.71, 14.29 and 17.86. For each rib spacing simulations are executed at six different relevant Reynolds numbers from 3800 to 18000. The thermo-hydraulic performance parameter for = 10.71 is found to be the best for the investigated range of parameters at a Reynolds number of 15000.

关键词: heat transfer     pressure drop     thermo-hydraulic performance parameter    

基于机器学习的多目标优化设计在按需喷墨生物打印中的应用 Article

时佳, 宋锦春, Bin Song, Wen F. Lu

《工程(英文)》 2019年 第5卷 第3期   页码 586-593 doi: 10.1016/j.eng.2018.12.009

摘要:

按需滴化微喷射(DOD)生物打印技术以其高通量效率和高成本效益在组织工程中得到了广泛的应用。然而,这种类型的生物打印技术面临诸如星形液滴产生、过大的液滴生成和过低的液滴速度等问题。这些问题降低了DOD打印技术的稳定性和精度,打乱了细胞排列,进一步产生结构误差。为了解决这些问题,本文提出了一种基于全连接神经网络(FCNN)的DOD打印参数多目标优化(MOO)设计方法。该MOO问题包括两个目标函数:利用FCNN开发星形液滴产生模型;减小液滴直径,提高液滴速度。为了寻找MOO 问题的帕累托最优解集,本文提出了结合采用Adam算法的混合子梯度下降束法(MSGDB),并采用基于自适应学习速率算法的混合子梯度下降束法(HMSGDBA)。通过与MSGDB的比较研究,证明了HMSGDBA 的优越性。实验结果表明,使用该方法优化可得到稳定的单滴打印过程,液滴速度由0.88 m·s–1 提高到2.08 m·s–1。该方法能提高打印精度和稳定性,对实现精密细胞阵列和复杂的生物功能具有重要意义。此外,对细胞打印实验平台的搭建具有指导意义。

关键词: 按需滴化微喷射生物打印     喷墨打印     按需滴化微喷射生物打印     全连接神经网络    

CFD simulation on shell-and-tube heat exchangers with small-angle helical baffles

Minhua ZHANG,Fang MENG,Zhongfeng GENG

《化学科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 183-193 doi: 10.1007/s11705-015-1510-x

摘要: Shell-and-tube heat exchanger with helical baffles is superior to that with segmental baffles in reducing pressure drop, eliminating dead zone and lowering the risks of vibration of tube bundle. This paper focused on the small-angle helical baffles that have been merely reported in open literature. These baffles are noncontinuous helical baffles with a helix angle of 10° to 30°, and their shapes are 1/4 ellipse, 1/4 sector and 1/3 sector. To assess the integrative performance, /? is employed, and the calculated results show that among the three baffle shapes the heat exchangers with a 1/4 sector helical baffle have the lowest pressure drop. At = 10° and 20°, 1/4 sector helical baffle heat exchangers show the best integrative performance; at = 30°, 1/4 ellipse and 1/4 sector helical baffle heat exchangers perform almost the same. For the study of helix angles, we found that 30° has the best integrative performance at low mass flow rate, almost the same as 20° at high mass flow rate.

关键词: heat transfer     pressure drop     helical baffle     CFD    

标题 作者 时间 类型 操作

Experimental studies on the axial crash behavior of aluminum foam-filled hat sections

WANG Qing-chun, FAN Zi-jie, GUI Liang-jin, WANG Zheng-hong, FU Zi-lai

期刊论文

Evaluation of strategies for the subsequent use of CO 2

Marc SCHAEFER, Frank BEHRENDT, Thomas HAMMER,

期刊论文

CFD evaluation of pressure drop across a 3-D filter housing for industrial gas turbine plants

Fidelis I. ABAM,Samuel O. EFFIOM,Olayinka S. OHUNAKIN

期刊论文

A biofilter model for simultaneous simulation of toluene removal and bed pressure drop under varied inlet

Jinying XI,Insun KANG,Hongying HU,Xian ZHANG

期刊论文

Ultrasound-assisted emulsification solidified floating organic drop microextraction for the determination

Qingyun CHANG, Jingwen ZHANG, Xin DU, Jingjun MA, Jingci LI,

期刊论文

Hybrid intelligent water drop bundled wavelet neural network to solve the islanding detection by inverter-based

Mehrdad TARAFDAR HAGH,Homayoun EBRAHIMIAN,Noradin GHADIMI

期刊论文

The investigation of pressure drop in moving-beds

CHEN Yunhua, ZHU Xuedong, WU Yongqiang, ZHU Zibin

期刊论文

产品跌落冲击耐撞性能稳健设计研究进展

杨书仪,刘德顺,赵继云,文泽军

期刊论文

Pressure drop analysis on the positive half-cell of a cerium redox flow battery using computational fluid

Fernando F. Rivera, Berenice Miranda-Alcántara, Germán Orozco, Carlos Ponce de León, Luis F. Arenas

期刊论文

低高宽比矩形微通道中流动沸腾的压降特性

张炳雷,徐进良,肖泽军

期刊论文

metaheuristic optimizations (SCE and ABC) for prediction of compressive strength of concrete using rebound hammer

Dung Quang VU; Fazal E. JALAL; Mudassir IQBAL; Dam Duc NGUYEN; Duong Kien TRONG; Indra PRAKASH; Binh Thai PHAM

期刊论文

Numerical study of droplet dynamics impinging onto steel plate covered with scale layer

Jan BOHá?EK, Ale? HORáK

期刊论文

Heat transfer and fluid flow analysis of an artificially roughened solar air heater: a CFD based investigation

Anil Singh YADAV,J. L. BHAGORIA

期刊论文

基于机器学习的多目标优化设计在按需喷墨生物打印中的应用

时佳, 宋锦春, Bin Song, Wen F. Lu

期刊论文

CFD simulation on shell-and-tube heat exchangers with small-angle helical baffles

Minhua ZHANG,Fang MENG,Zhongfeng GENG

期刊论文