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Structure improvement and strength finite element analysis of VHP welded rotor of 700°C USC steam turbine

Jinyuan SHI,Zhicheng DENG,Yong WANG,Yu YANG

《能源前沿（英文）》 2016年 第10卷 第1期   页码 88-104 doi: 10.1007/s11708-015-0387-1

摘要： The optimized structure strength design and finite element analysis method for very high pressure (VHP) rotors of the 700°C ultra-super-critical (USC) steam turbine are presented. The main parameters of steam and the steam thermal parameters of blade stages of VHP welded rotors as well as the start and shutdown curves of the steam turbine are determined. The structure design feature, the mechanical models and the typical position of stress analysis of the VHP welded rotors are introduced. The steady and transient finite element analysis are implemented for steady condition, start and shutdown process, including steady rated condition, 110% rated speed, 120% rated speed, cold start, warm start, hot start, very hot start, sliding-pressure shutdown, normal shutdown and emergency shutdown, to obtain the temperature and stress distribution as well as the stress ratio of the welded rotor. The strength design criteria and strength analysis results of the welded rotor are given. The results show that the strength design of improved structure of the VHP welded rotor of the 700°C USC steam turbine is safe at the steady condition and during the transient start or shutdown process.

关键词： 700°C ultra-super-critical unit     steam turbine     very high pressure rotor     structure strength design     strength design criteria     finite element analysis    

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saccharification and fermentation of sweet potato powder for the production of ethanol under conditions of veryhigh gravity

Yinxiu CAO, Hongchi TIAN, Kun YAO, Yingjin YUAN

《化学科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 318-324 doi: 10.1007/s11705-010-1026-3

摘要： Due to its merits of drought tolerance and high yield, sweet potatoes are widely considered as a potential alterative feedstock for bioethanol production. Very high gravity (VHG) technology is an effective strategy for improving the efficiency of ethanol fermentation from starch materials. However, this technology has rarely been applied to sweet potatoes because of the high viscosity of their liquid mash. To overcome this problem, cellulase was added to reduce the high viscosity, and the optimal dosage and treatment time were 8 U/g (sweet potato powder) and 1 h, respectively. After pretreatment by cellulase, the viscosity of the VHG sweet potato mash (containing 284.2 g/L of carbohydrates) was reduced by 81%. After liquefaction and simultaneous saccharification and fermentation (SSF), the final ethanol concentration reached 15.5% (v/v), and the total sugar conversion and ethanol yields were 96.5% and 87.8%, respectively.

关键词： bioethanol     sweet potato     very high gravity     viscosity reduction     simultaneous saccharification and fermentation    

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Linear viscoelastic behavior of asphalt binders and mixtures containing very high percentages of reclaimed

《结构与土木工程前沿（英文）》   页码 1211-1227 doi: 10.1007/s11709-023-0983-9

摘要： The primary aim of this study is to correlate the impact of aggregates, if any, on the viscoelastic behavior of rejuvenated asphalt mixtures containing very high amounts of reclaimed asphalt pavement (RAP) (> 50%). First, gradation of 100% RAP was rectified, using a modified Bailey method by adding virgin aggregates to achieve two coarse dense-graded and one fine dense-graded blends. Complex modulus test was then performed from −35 to +35 °C and 0.01–10 Hz. In addition to performance grade (PG) testing, extracted and recovered binders from different asphalt mixtures underwent shear complex modulus test within −8 °C to high temperature PG and frequencies from 0.001 to 30 Hz. Cole−Cole, Black space, complex modulus and phase angle master curves were constructed and Shift-Homothety-Shift in time-Shift (SHStS) transformation was used to compare the linear viscoelastic behavior of asphalt binders and mixtures. The influence of aggregates on the viscoelastic behavior of asphalt mixtures depends on temperature and/or frequency. The role of asphalt binders in the behavior of asphalt mixtures is more pronounced at high temperatures and the effect of the aggregate structure increases as the temperature falls. The maximum difference (60% to 70%) in the viscoelastic behavior of the binder and mixture based on SHStS transformed Cole−Cole curves is within the phase angle of 15°–20°.

关键词： RAP     complex modulus     SHStS transformation     rejuvenation     behavior of asphalt binder and mixture    

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Effects of rotor and stator geometry on dissolution process and power consumption in jet-flow high shear

Lin Yang, Wenpeng Li, Junheng Guo, Wei Li, Baoguo Wang, Minqing Zhang, Jinli Zhang

《化学科学与工程前沿（英文）》 2021年 第15卷 第2期   页码 384-398 doi: 10.1007/s11705-020-1928-7

摘要： The jet-flow high shear mixer (JF-HSM) is a new type of intensified equipment with special configurations of the rotor and the stator. The mass transfer property and power consumption were studied in the solid-liquid system for a series of JF-HSMs involving different configuration parameters, such as rotor diameter, rotor blade inclination, rotor blade bending direction, stator diameter, and stator bottom opening diameter. The flow characteristics were examined by computational fluid dynamic simulations. Results indicate that the turbulent power consumption of the JF-HSM is affected by the change in rotor blade inclination and stator bottom opening. With the increase in the shear head size and the change in the rotor into a backward-curved blade, the solid-liquid mass transfer rate can be remarkably increased under the same input power. Dimensionless correlations for the mass transfer coefficient and power consumption were obtained to guide the scale-up design and selection of such a new type of equipment to intensify the overall mixing efficiency.

关键词： jet-flow high shear mixer     solid particle dissolution     power consumption characteristics     CFD Simulation    

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甚高频雷达复杂场景中目标高度和多径衰减联合估计 Research Articles

陈胜,赵永波,胡毅立,曹成虎,庞晓娇

《信息与电子工程前沿（英文）》 2022年 第23卷 第6期   页码 937-949 doi: 10.1631/FITEE.2100003

摘要：

由于多径效应的影响，甚高频雷达低角估计是雷达领域难题之一，尤其是在反射条件未知的复杂情况下，低角估计更难解决。针对这一问题，提出一种目标高度和多径衰减联合估计算法。该算法首先利用数据本身的特性估算反射系数幅度，当该幅度估计值很小时，认为没有反射信号，然后将反射系数的相位和直达信号与反射信号之间的相位差当作同一部分，即多径相位衰减，并对其进行搜索。推导了该算法的克拉美罗界。最后，计算机仿真和实测数据处理结果表明，该算法在复杂场景下具有良好估计性能，并且在仅有单次快拍的条件下仍能较好地工作。

关键词： 低角估计；甚高频雷达；复杂场景；多径效应；高度估计    

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A novel high-temperature and high-pressure hydraulic pump based on mononeuron control

Linhui ZHAO, Xin FANG

《机械工程前沿（英文）》 2009年 第4卷 第2期   页码 219-223 doi: 10.1007/s11465-009-0024-y

摘要： Based on structures and characteristics of traditional hydraulic pumps, this paper proposes a novel high-temperature and high-pressure hydraulic pump (HHHP) that can work under 150°C and 28 MPa to overcome problems of traditional high-temperature plunger pumps. The HHHP is designed with the structure of mechanical division and double cylinder parallel. The control signals of two cylinders are two separate triangle waveforms with 90° phase difference. Because the output waveforms of two cylinders have the same characteristics as the control signals, the HHHP can obtain a stable output after two separate waveforms are superposed. A mononeuron self-adaptive PID control algorithm is also improved by modifying parameters and . Two improved controllers are used to control the two cylinders, respectively, making two displacements of plungers match each other. Therefore, reduced fluctuations and stable pressure output is obtained. Besides simulation, tests on the built prototype test system are carried out to verify the performance of HHHP. Results show that the improved control approach can limit fluctuations to a lower level and the HHHP system attains good outputs under different signal periods and different pressures.

关键词： mononeuron PID control     hydraulic pump     pressure fluctuation    

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Assessment and validation of liquid breakup models for high-pressure dense diesel sprays

Yi REN,Xianguo LI

《能源前沿（英文）》 2016年 第10卷 第2期   页码 164-175 doi: 10.1007/s11708-016-0407-9

摘要： Liquid breakup in fuel spray and atomization significantly affects the consequent mixture formation, combustion behavior, and emission formation processes in a direct injection diesel engine. In this paper, different models for liquid breakup processes in high-pressure dense diesel sprays and its impact on multi-dimensional diesel engine simulation have been evaluated against experimental observations, along with the influence of the liquid breakup models and the sensitivity of model parameters on diesel sprays and diesel engine simulations. It is found that the modified Kelvin-Helmholtz (KH)–Rayleigh-Taylor (RT) breakup model gives the most reasonable predicted results in both engine simulation and high-pressure diesel spray simulation. For the standard KH-RT model, the model constant for the breakup length has a significant effect on the predictability of the model, and a fixed value of the constant cannot provide a satisfactory result for different operation conditions. The Taylor-analogy-breakup (TAB) based models and the RT model do not provide reasonable predictions for the characteristics of high-pressure sprays and simulated engine performance and emissions.

关键词： breakup model     diesel engine     high-pressure injection     simulations    

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Continuous deacylation of amides in a high-temperature and high-pressure microreactor

《化学科学与工程前沿（英文）》 2022年 第16卷 第12期   页码 1818-1825 doi: 10.1007/s11705-022-2182-y

摘要： The deacylation of amides, which is widely employed in the pharmaceutical industry, is not a fast reaction under normal conditions. To intensify this reaction, a high-temperature and high-pressure continuous microreaction technology was developed, whose space-time yield was 49.4 times that of traditional batch reactions. Using the deacylation of acetanilide as a model reaction, the effects of the temperature, pressure, reaction time, molar ratio of reactants, and water composition on acetanilide conversion were carefully studied. Based on the rapid heating and cooling capabilities, the kinetics of acetanilide deacylation at high temperatures were investigated to determine the orders of reactants and activation energy. This microreaction technology was further applied to a variety of other amides to understand the influence of substituents and steric hindrance on the deacylation reaction.

关键词： amide deacylation     microreactor     flow chemistry     reaction intensification    

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表面驱动高压工艺 Perspective

Keith E. Gubbins, Kai Gu, Liangliang Huang, Yun Long, J. Matthew Mansell, Erik E. Santiso, Kaihang Shi, Małgorzata Ś liwińska-Bartkowiak, Deepti Srivastava

《工程（英文）》 2018年 第4卷 第3期   页码 311-320 doi: 10.1016/j.eng.2018.05.004

摘要：

许多化学过程都要在高压下进行，因为高压状态能提高产率，加快化学反应的速率，分离过程中提高溶剂功率，并通过增加分子能量和分子碰撞率来克服活化作用的障碍。通过金刚石砧室压力能高达数百万巴，实验室就能达到这种效果，因此为利用热力学、输运和电子性质来进行化学合成以及合成新材料提供了新的途径。然而，在工业规模上，高压工艺目前正受到压缩成本和有限材料的约束，因此很少有工业过程能够在在压力超过25 MPa的情况下进行。本文提出了一种高压工艺的替代方法，即利用来自固体底物的表面驱动的相互作用产生非常高的局部压力。近期的实验和分子模拟表明，这种相互作用可以产生高达数万巴的局部压力，某些情况下甚至可以达到数百万巴。由于活跃的高压区域分布不均匀，压力在不同方向上存在差异。在许多情况下，增强最多的是平行于底物表面的压力（切向压力）。这种压力是施加在要加工的分子上的，而不是施加在固体底物或容器上。本文综述了现阶段对这种增压的认识，并讨论了一种基于表面驱动力的可行方法来达到高压处理的效果。这种表面驱动高压处理的优点在于，相比传统的整体相位处理，它能达到更高的压力，因为它不需要机械压缩。此外，过程中没有对容器施加更大的压力，因此不用担心材料受损。

关键词： 限制     高压     高压相     高压反应     高压制造     高压化学工艺    

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Confining pressure effect on dynamic response of high rockfill dam

Xuexing CAO, Yunlong HE, Kun XIONG,

《结构与土木工程前沿（英文）》 2010年 第4卷 第1期   页码 116-126 doi: 10.1007/s11709-010-0014-5

摘要： Studies show that the dynamic properties of rockfill are strongly dependent on the confining pressure. Therefore, confining pressure effect has become a very important factor in the seismic analysis of high rockfill dam. The relationships of dynamic shear modulus versus dynamic shear strain and damping ratio versus dynamic shear strain had been improved to a certain degree on the basic of widely used Hardin-Drnevich constitutive model in this paper. Then a new model that could consider confining pressure effect has been established. Regression analysis was carried out of the dynamic triaxial experimental data of the damming materials in the Changheba hydropower station of Sichun Province, China. The results show that, the new model can fit the test data well under various confining pressures. A corresponding computational procedure was compiled and applied in the dynamic response analysis of the Changheba Dam. Comparing the calculation results between the new constitutive model and the ordinary Hardin-Drnevich model, it can be seen that the result is conservative to some extent without considering confining pressure effect.

关键词： confining pressure effect     high rockfill dam     dynamic response     Hardin-Drnevich constitutive model    

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Terahertz time-domain spectroscopy of high-pressure flames

Jason BASSI, Mark STRINGER, Bob MILES, Yang ZHANG

《能源前沿（英文）》 2009年 第3卷 第2期   页码 123-133 doi: 10.1007/s11708-009-0033-x

摘要： Laser spectroscopy in the visible and near infrared is widely used as a diagnostic tool for combustion devices, but this approach is difficult at high pressures within a sooty flame itself. High soot concentrations render flames opaque to visible light, but they remain transparent to far-infrared or terahertz (THz) radiation. The first far-infrared absorption spectra, to the best of our knowledge, of sooty, non-premixed, ethylene high-pressure flames covering the region of 0.2-2.5 THz is presented. A specially designed high-pressure burner which is optically accessible to THz radiation has been built allowing flame transmission measurements up to pressures of 1.6 MPa. Calculations of the theoretical combustion species absorption spectra in the 0.2-3 THz range have shown that almost all the observable features arise from H O. A few OH (1.84 and 2.51 THz), CH (2.58 THz), and NH (1.77 and 2.95 THz) absorption lines are also observable in principle. A large number of H O absorption lines are observed in the ground vibrational in a laminar non-premixed, sooty flame (ethylene) at pressures up to 1.6 MPa.

关键词： terahertz time-domain spectroscopy     high-pressure flames     H2O absorption lines    

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vapor deposition of excellent a-Si:H passivation layers for a-Si:H/c-Si heterojunction solar cells at highpressure and high power

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    

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Spray characteristics of high-pressure swirl injector fueled with alcohol

WANG Xibin, CHEN Wansheng, GAO Jian, JIANG Deming, HUANG Zuohua

《能源前沿（英文）》 2007年 第1卷 第1期   页码 105-112 doi: 10.1007/s11708-007-0012-z

摘要： The spray characteristics of methanol and ethanol with high-pressure swirl injector were explored experimentally and numerically. Experimental results show that the spray characteristics of methanol and ethanol had displayed the same trends as that of gasoline. Under the low back-pressure ambient conditions, the spray behavior exhibited a hollow cone with wide spray angle and initial spray slug at the tip, while the spray presented a solid cone in the case of high back-pressure. Vortexes in the opposite direction existed in the rear part of the spray under low back-pressure ambient conditions while the vortexes formed in the middle part under high back-pressure ambient conditions. Experiments also showed that methanol had the largest cone angle, while ethanol and gasoline presented almost the same cone angle. Simulation results indicated that methanol and ethanol had a slightly larger Sauter mean diameter (SMD) than that of gasoline with swirl injector. The SMD profile of methanol coincided well with that of ethanol under low back-pressure ambient conditions, but displayed a slightly larger value under high back-pressure due to fuel evaporation. Numerical simulation could successfully demonstrate the spray characteristics of high-pressure swirl injector for methanol and ethanol fuels.

关键词： low back-pressure     diameter     initial spray     hollow     middle    

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大直径泥水盾构带压进仓地层加固及保压技术

孟海峰,苏清贵,翟志国

《中国工程科学》 2010年 第12卷 第12期   页码 70-74

摘要：

通过对北京铁路地下直径线带压进仓换刀工程实例的分析，探讨了注浆加固及桩基加固在地层加固中的应用，分析了带压进仓的漏气原因并采取相应的应对措施，保证了盾构的正常施工。

关键词： 盾构     带压进仓     保压     注浆    

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Wind tunnel test study on the wind pressure coefficient of claddings of high-rise buildings

Yong QUAN, Yi LIANG, Fei WANG, Ming GU

《结构与土木工程前沿（英文）》 2011年 第5卷 第4期   页码 518-524 doi: 10.1007/s11709-011-0128-4

摘要： The area-averaged most unfavorable wind pressure coefficients (MUWPCs) on various regions of building surfaces and the influence of the side ratio and the terrain category were studied based on wind tunnel test data of scale models of typical high-rise buildings with rectangular cross-sections. The negative area-averaged MUWPCs in the middle-height edge areas generally increased with an increasing / side ratio. The area-averaged MUWPCs can be well fitted with a function of the average area reduced by the square of the building depth, . In addition, no unique pattern was found for the effect of the terrain category on the MUWPCs.

关键词： side ratio     area-averaged pressure coefficients     cladding     terrain category    

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标题 作者 时间 类型 操作

Structure improvement and strength finite element analysis of VHP welded rotor of 700°C USC steam turbine

Jinyuan SHI,Zhicheng DENG,Yong WANG,Yu YANG

期刊论文

saccharification and fermentation of sweet potato powder for the production of ethanol under conditions of veryhigh gravity

Yinxiu CAO, Hongchi TIAN, Kun YAO, Yingjin YUAN

期刊论文

Linear viscoelastic behavior of asphalt binders and mixtures containing very high percentages of reclaimed

期刊论文

Effects of rotor and stator geometry on dissolution process and power consumption in jet-flow high shear

Lin Yang, Wenpeng Li, Junheng Guo, Wei Li, Baoguo Wang, Minqing Zhang, Jinli Zhang

期刊论文

甚高频雷达复杂场景中目标高度和多径衰减联合估计

陈胜,赵永波,胡毅立,曹成虎,庞晓娇

期刊论文

A novel high-temperature and high-pressure hydraulic pump based on mononeuron control

Linhui ZHAO, Xin FANG

期刊论文

Assessment and validation of liquid breakup models for high-pressure dense diesel sprays

Yi REN,Xianguo LI

期刊论文

Continuous deacylation of amides in a high-temperature and high-pressure microreactor

期刊论文

表面驱动高压工艺

Keith E. Gubbins, Kai Gu, Liangliang Huang, Yun Long, J. Matthew Mansell, Erik E. Santiso, Kaihang Shi, Małgorzata Ś liwińska-Bartkowiak, Deepti Srivastava

期刊论文

Confining pressure effect on dynamic response of high rockfill dam

Xuexing CAO, Yunlong HE, Kun XIONG,

期刊论文

Terahertz time-domain spectroscopy of high-pressure flames

Jason BASSI, Mark STRINGER, Bob MILES, Yang ZHANG

期刊论文

vapor deposition of excellent a-Si:H passivation layers for a-Si:H/c-Si heterojunction solar cells at highpressure and high power

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

期刊论文

Spray characteristics of high-pressure swirl injector fueled with alcohol

WANG Xibin, CHEN Wansheng, GAO Jian, JIANG Deming, HUANG Zuohua

期刊论文

大直径泥水盾构带压进仓地层加固及保压技术

孟海峰,苏清贵,翟志国

期刊论文

Wind tunnel test study on the wind pressure coefficient of claddings of high-rise buildings

Yong QUAN, Yi LIANG, Fei WANG, Ming GU

期刊论文