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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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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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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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Numerical simulation of air flow field in high-pressure fan with splitter blades

LI Jianfeng, LU Junfu, ZHANG Hai, LIU Qing, YUE Guangxi

《能源前沿（英文）》 2008年 第2卷 第4期   页码 438-442 doi: 10.1007/s11708-008-0085-3

摘要： For a deeper understanding of the flow characteristics in the high-pressure centrifugal blower of a fan of Model 9-26 with splitter blades, a three dimensional (3-D) numerical simulation of air flows in the fan was conducted with FLUENT software. The standard - turbulent model and unstructured grids were used. The computational fluid dynamics (CFD) results showed that the performance of a fan could be improved by adding the splitter blades in the channel among the leaf blades. Under operational conditions, with the presence of splitter blades, the air flow rate of the fan increased about 5% and the total pressure at the outlet of the fan increased about 10% on average. It was also found that the length of the splitter blades affected the air flow and pressure drop. There is an optimal value for the length. The simulation results provide helpful information for improving the fan performance.

关键词： splitter     numerical simulation     presence     unstructured     operational    

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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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Development of lunar regolith-based composite for - 3D printing via high-pressure extrusion system

《机械工程前沿（英文）》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0745-8

摘要： To fully utilize the in-situ resources on the moon to facilitate the establishment of a lunar habitat is significant to realize the long-term residence of mankind on the moon and the deep space exploration in the future. Thus, intensive research works have been conducted to develop types of 3D printing approach to adapt to the extreme environment and utilize the lunar regolith for in-situ construction. However, the in-situ 3D printing using raw lunar regolith consumes extremely high energy and time. In this work, we proposed a cost-effective melting extrusion system for lunar regolith-based composite printing, and engineering thermoplastic powders are employed as a bonding agent for lunar regolith composite. The high-performance nylon and lunar regolith are uniformly pre-mixed in powder form with different weight fractions. The high-pressure extrusion system is helpful to enhance the interface affinity of polymer binders with lunar regolith as well as maximize the loading ratio of in-situ resources of lunar regolith. Mechanical properties such as tensile strength, elastic modulus, and Poisson’s ratio of the printed specimens were evaluated systematically. Especially, the impact performance was emphasized to improve the resistance of the meteorite impact on the moon. The maximum tensile strength and impact toughness reach 36.2 MPa and 5.15 kJ/m2, respectively. High-pressure melt extrusion for lunar regolith composite can increase the effective loading fraction up to 80 wt.% and relatively easily adapt to extreme conditions for in-situ manufacturing.

关键词： in-situ resource utilization     melt extrusion molding     lunar regolith-based composites     mechanical properties     additive manufacturing    

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Properties of Ag-doped Bi-Sb alloys as thermoelectric conversion materials for solid state refrigeration

Wen XU, Laifeng LI, Rongjin HUANG, Min ZHOU, Liyun ZHENG, Linghui GONG, Chunmei SONG

《能源前沿（英文）》 2009年 第3卷 第1期   页码 90-93 doi: 10.1007/s11708-009-0005-1

摘要： The energy conversion properties of Bi-Sb system thermoelectric materials doped by Ag was investigated. Bi Sb Ag ( =0, 1, 2, 3, 4) alloys with Ag substitution for Sb were synthesized by mechanical alloying and then pressed under 5 GPa at 523 K for 30 min. The phase structure of the alloys was characterized by X-ray diffraction. The electric conductivities and the seebeck coefficients were measured at the temperature range of 80-300 K. The results reveal that the electric conductivities of the Ag-doped Bi-Sb alloys are highly improved. The power factor of Bi Sb Ag reaches a maximum value of 2.98×10 W/(K ?m) at 255 K, which is about three times that of the un-doped sample Bi Sb at the same temperature.

关键词： thermoelectric conversion materials     high-pressure sintering     thermoelectric properties    

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and laboratory experimental studies on hard-rock tunnel excavation based on disc cutter coupled with high-pressure

《结构与土木工程前沿（英文）》   页码 1370-1386 doi: 10.1007/s11709-023-0947-0

摘要： The tunnel boring machine (TBM) is typically used in hard-rock tunnel excavation. Owing to the unsatisfactory adaptability of TBM to the surrounding rock, when crossing high-strength and high-wear strata, the TBM can easily cause defects, such as abnormal wear on cutters and overload damage to bearings, thus affecting the construction efficiency and cost. Therefore, high-pressure waterjet technology should be applied to assist in rock breaking for efficient TBM tunneling. In this study, the effects of water pressure, nozzle diameter, and nozzle speed on cutting are investigated via laboratory experiments of cutting hard rock using high-pressure waterjets. The penetration performance of the TBM under different water pressures is investigated via a field industrial penetration test. The results show that high-pressure waterjets are highly efficient for rock breaking and are suitable for industrial applications, as they can accommodate the advancing speed of the TBM and achieve high-efficiency rock breaking. However, during the operation of high-pressure waterjets, the ambient temperature and waterjet temperature in the tunnel increase significantly, which weakens the cooling effect of the cutterhead and decreases the construction efficiency of the TBM. Therefore, temperature control and cooling measures for high-pressure waterjets during their long-term operation must be identified. This study provides a useful reference for the design and construction of high-pressure water-jet-assisted cutterheads for breaking road headers.

关键词： tunnel boring machine     hard-rock cutting     free face     disc cutter     rock-cutting efficiency    

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Pilot study for the treatment of sodium and fluoride-contaminated groundwater by using high-pressure

Xiaomao WANG,Hongwei YANG,Zhenyu LI,Shaoxia YANG,Yuefeng XIE

《环境科学与工程前沿（英文）》 2015年 第9卷 第1期   页码 155-163 doi: 10.1007/s11783-014-0740-3

摘要： High-pressure membrane process is one of the cost-effective technologies for the treatment of groundwater containing excessive dissolved solids. This paper reports a pilot study in treating a typical groundwater in Huaibei Plain containing excessive sodium, sulfate and fluoride ions. Three membrane systems were set up and two brands of reverse osmosis (RO), four low-pressure RO (LPRO) and one tight nanofiltration (NF) membranes were tested under this pilot study. An apparent recovery rate at about 75% was adopted. Cartridge filtration, in combination with dosing antiscalent, was not sufficient to reduce the fouling potential of the raw water. All RO and LPRO systems (except for the two severely affected by membrane fouling) demonstrated similar rejection ratios of the conductivity (~98.5%), sodium (~98.5%) and fluoride (~99%). Membrane fouling substantially reduced the rejection performance of the fouled membranes. The tight NF membrane also had a good rejection on conductivity (95%), sodium (94%) and fluoride (95%). All membranes rejected sulfate ion almost completely (more than 99%). The electricity consumptions for the RO, LPRO and NF systems were 1.74, 1.10 and 0.72 kWh?m treated water, respectively. The estimated treatment costs by using typical RO, LPRO and tight NF membrane systems were 1.21, 0.98 and 0.96 CNY?m finished water, respectively. A treatment process consisting of either LPRO or tight NF facilities following multi-media filtration was suggested.

关键词： reverse osmosis (RO)     nanofiltration (NF)     water quality standards     sodium     fluoride     cost estimation    

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Development of a simplified n-heptane/methane model for high-pressure direct-injection natural

Jingrui LI, Haifeng LIU, Xinlei LIU, Ying YE, Hu WANG, Xinyan WANG, Hua ZHAO, Mingfa YAO

《能源前沿（英文）》 2021年 第15卷 第2期   页码 405-420 doi: 10.1007/s11708-021-0718-3

摘要： High-pressure direct-injection (HPDI) of natu-ral gas is one of the most promising solutions for future ship engines, in which the combustion process is mainly controlled by the chemical kinetics. However, the employment of detailed chemical models for the multi-dimensional combustion simulation is significantly expensive due to the large scale of the marine engine. In the present paper, a reduced -heptane/methane model consisting of 35-step reactions was constructed using multiple reduction approaches. Then this model was further reduced to include only 27 reactions by utilizing the HyChem (Hybrid Chemistry) method. An overall good agreement with the experimentally measured ignition delay data of both -heptane and methane for these two reduced models was achieved and reasonable predictions for the measured laminar flame speeds were obtained for the 35-step model. But the 27-step model cannot predict the laminar flame speed very well. In addition, these two reduced models were both able to reproduce the experimentally measured in-cylinder pressure and heat release rate profiles for a HPDI natural gas marine engine, the highest error of predicted combustion phase being 6.5%. However, the engine-out CO emission was over-predicted and the highest error of predicted NO emission was less than 12.9%. The predicted distributions of temperature and equivalence ratio by the 35-step and 27-step models are similar to those of the 334-step model. However, the predicted distributions of OH and CH O are significantly different from those of the 334-step model. In short, the reduced chemical kinetic models developed provide a high-efficient and dependable method to simulate the characteristics of combustion and emissions in HPDI natural gas marine engines.

关键词： high-pressure direct-injection     natural gas     chemical kinetics     combustion modelling     marine engine    

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Separation of

Wei Hou, Qingjun Zhang, Aiwu Zeng

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1169-1184 doi: 10.1007/s11705-020-2018-6

摘要： In this study, vapor recompression and heat integration assisted distillation arrangements with either the low or high pressure in the reflux drum are proposed to reduce and/or eliminate the application of the costly refrigerant for the separation of -heptane and isobutanol mixture. The high-pressure arrangement with vapor recompression and heat integration is the most attractive among these four intensified configurations since it can reduce total annual cost by 18.10%, CO emissions by 75.01% based on natural gas (78.78% based on heavy oil fuel), and second-law efficiency by 61.20% compared to a conventional refrigerated distillation system. Furthermore, exergy destruction in each component is calculated for the heat integration configurations and is shown in pie diagrams. The results demonstrate that the high-pressure configuration presents unique advantages in terms of thermodynamic efficiency compared to the low-pressure case. In addition, dynamic control investigation is performed for the economically efficient arrangement and good product compositions are well controlled through a dual-point temperature control strategy with almost negligible product offsets and quick process responses when addressing 20% step changes in production rate and feed composition. Note that there are no composition measurement loops in our developed control schemes.

关键词： n-heptane/isobutanol     vapor recompression     heat integration     low and/or high-pressure options    

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高压富水断层“外堵内固注浆法”设计新理念与工程实践

张民庆,张梅

《中国工程科学》 2009年 第11卷 第12期   页码 26-34

摘要：

宜万铁路齐岳山隧道F11断层由断层角砾岩、破裂岩、断层泥组成，断层内富含高压水，超前探孔单孔最大涌水量1 800 m3/h，水压力2.5 MPa。针对F11高压富水断层，前期按“以堵为主、限量排放”施工原则，采取全断面帷幕注浆措施，注浆工程量大、进度慢。为及早攻克F11高压富水断层，建设单位多次邀请院士、专家现场踏勘、研讨，提出“注浆加固、分水降压、快挖快封、加强监测、综合治理”施工技术方案，将全断面帷幕注浆调整为外堵内固注浆。对于高压富水断层，通常的设计是加固圈厚一些、加固体强一些，而外堵内固注浆是将隧道周边岩体、水量及水压力分布假定为不均匀性，从而通过超前探孔锁定弱水区和强水区，针对弱水区采取基本注浆，对强水区采取加强注浆，注浆机理为“封堵裂隙、减少水量；固结围岩、改良地层。”注浆时，先通过区域定位孔进行无约束注浆堵水，从而使地层中水量得到有效控制，然后按“合理步距、封堵水流，由外到内、环环相扣，间隔跳孔、锁定水源，增加补孔、区域加强”的注浆理念进行注浆施工。通过现场实践，外堵内固注浆能达到注浆堵水和加固效果。外堵内固注浆与全断面帷幕注浆相比，注浆孔数量和注浆量减少50 %，在水量大时，注浆进度提高80 %，一般情况下提高50 %以上，因此，外堵内固注浆具有广阔的推广应用价值。

关键词： 高压富水断层     不均匀性     注浆堵水加固     外堵内固注浆     创新    

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未来飞机液压系统的特点

王占林,陈斌

《中国工程科学》 1999年 第1卷 第3期   页码 5-10

摘要：

现代飞机舵面操纵系统与动力收放系统几乎都是液压驱动的。随着飞机特别是军用飞机的发展，对机载液压系统提出了更高的要求。文章对飞机特别是军用飞机液压系统的主要发展趋势进行了综述，并对国内外的飞机液压系统的研究工作进行了一定的介绍。指出：质量轻、体积小、高压化、大功率、变压力、智能化、集成化、余度技术等是未来飞机液压系统的主要发展趋势，尤其是高压变压力泵源系统对未来飞机的发展尤为重要。

关键词： 机载液压系统     高压化     变压力     余度     功率电传    

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高压高产含硫气井测试技术及应用

王世泽,唐瑞江, 赵祚培,杜林

《中国工程科学》 2010年 第12卷 第10期   页码 56-60

摘要：

川东北海相气藏埋藏深、温度压力高、普遍含硫、平面及纵向产量变化大，测试工艺复杂，面临井下工具受限、井下事故复杂、井控及环境污染风险大等难题。在川东北高含硫气井测试实践与经验基础上，形成了高压高产含硫气井测试技术。形成了三类六套APR射孔—酸压—测试联作短期测试管柱；管柱力学分析、多级压力控制、国产抗硫及复合地面流程等测试配套工艺满足各类测试要求；以压井、防喷、防漏为主的测试应急方案及措施确保了作业安全。该技术在YB1-侧1，YB12，HB1-1D等井中成功应用，为该类气田勘探开发的顺利进行提供了技术支撑。

关键词： 高压高产     含硫     气藏     测试    

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标题 作者 时间 类型 操作

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

Terahertz time-domain spectroscopy of high-pressure flames

Jason BASSI, Mark STRINGER, Bob MILES, Yang ZHANG

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

Numerical simulation of air flow field in high-pressure fan with splitter blades

LI Jianfeng, LU Junfu, ZHANG Hai, LIU Qing, YUE Guangxi

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

Development of lunar regolith-based composite for - 3D printing via high-pressure extrusion system

期刊论文

Properties of Ag-doped Bi-Sb alloys as thermoelectric conversion materials for solid state refrigeration

Wen XU, Laifeng LI, Rongjin HUANG, Min ZHOU, Liyun ZHENG, Linghui GONG, Chunmei SONG

期刊论文

and laboratory experimental studies on hard-rock tunnel excavation based on disc cutter coupled with high-pressure

期刊论文

Pilot study for the treatment of sodium and fluoride-contaminated groundwater by using high-pressure

Xiaomao WANG,Hongwei YANG,Zhenyu LI,Shaoxia YANG,Yuefeng XIE

期刊论文

Development of a simplified n-heptane/methane model for high-pressure direct-injection natural

Jingrui LI, Haifeng LIU, Xinlei LIU, Ying YE, Hu WANG, Xinyan WANG, Hua ZHAO, Mingfa YAO

期刊论文

Separation of

Wei Hou, Qingjun Zhang, Aiwu Zeng

期刊论文

高压富水断层“外堵内固注浆法”设计新理念与工程实践

张民庆,张梅

期刊论文

未来飞机液压系统的特点

王占林,陈斌

期刊论文

高压高产含硫气井测试技术及应用

王世泽,唐瑞江, 赵祚培,杜林

期刊论文