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水平井 3

压裂 2

微地震监测 2

沉管隧道 2

裂缝 2

YAG激光淬火 1

mcr 1

β-粒子的横向振动 1

临界风速 1

主缆单元索股 1

井网 1

优化 1

低渗透 1

压裂裂缝 1

发动机缸体 1

固定床 1

地铁隧道 1

基础灌砂 1

多黏菌素耐药性 1

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A study of spray granulation in vibrated fluidized bed with internal heating tubes

Xiaoheng PAN, Shichao YE, Zeguang ZHANG, Li ZHANG, Xuejun ZHU

《化学科学与工程前沿（英文）》 2009年第3卷第1期页码 78-82 doi: 10.1007/s11705-009-0084-x

摘要： The granulation process in a vibrated fluidized bed with immersed horizontal heating tubes was studied in this paper, with small monoammonium phosphate particles as the initial particles and monoammonium phosphate solution sprayed on them. The concrete influences on the granulating performance of the immersed horizontal heating power, fluidizing gas velocity, vibration frequency and amplitude had been analyzed theoretically. The results show that appropriate vibration intensity is a preferred condition for the growth of partials, but the fine dust will become much more along with prolonged vibration. Increasing the heating power is beneficial to raise the growth rate. Particles will grow faster if the fluidizing gas velocity is higher, but this will cause more fine dust. The optimized condition of =0.002 m, =6.67 Hz, =1.4 m/s was given after the analysis of the experimental results. In the end, a semiempirical formula was derived from the experiment data, and the calculation results show good agreement with the experimental data.

关键词： vibrated fluidized bed immersed horizontal horizontal heating tubes spray granulation particle growth model

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Particle-scale simulation of fluidized bed with immersed tubes

ZHAO Yongzhi, JIANG Maoqiang, CHENG Yi

《化学科学与工程前沿（英文）》 2008年第2卷第3期页码 341-345 doi: 10.1007/s11705-008-0046-8

摘要： In order to simulate gas-solids flows with complex geometry, the boundary element method was incorporated into the implementation of a combined model of computational fluid dynamics and discrete element method. The resulting method was employed to simulate hydrodynamics in a fluidized bed with immersed tubes. The transient simulation results showed particle and bubble dynamics. The bubble coalescence and break-up behavior when passing the immersed tubes was successfully predicted. The gas-solid flow pattern in the fluidized bed is changed greatly because of the immersed tubes. As particles and gas are come in contact with the immersed tubes, the gas bubbles will be deformed. The collisions between particles and tubes will make the tubes surrounded by air pockets most of the time and this is unfavorable for the heat transfer between particles and tubes.

关键词： unfavorable computational gas-solid particle discrete

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Performance analysis of an air-source heat pump using an immersed water condenser

Jie JI, Huide FU, Hanfeng HE, Gang PEI,

《能源前沿（英文）》 2010年第4卷第2期页码 234-245 doi: 10.1007/s11708-009-0056-3

摘要： A distributed model of an air-source heat pump (ASHP) system and its experimental setup using an immersed water condenser were presented. Dynamic performance of the ASHP was then evaluated by both simulation and experiment. The results indicated that the system coefficient of performance (COP) decreased as the condenser temperature increased, ranging from 4.41 to 2.32 with the average COP equaling 3.29 during the experiment. Comparisons between simulation results and experimental measurements demonstrated that the model was able to yield satisfactory predictions. Furthermore, temperature profiles of the refrigerant in the evaporator and condenser were also given. This paper provides the theoretical and experimental background for ASHP system optimization and a valuable reference for a solar air-source heat pump water heater when the solar irradiation energy is insufficient on cloudy or rainy days.

关键词： air-source heat pump distributed model immersed water condenser

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Comparative study on foundation treatment methods of immersed tunnels in China

Shaochun WANG, Xuehui ZHANG, Yun BAI

《结构与土木工程前沿（英文）》 2020年第14卷第1期页码 82-93 doi: 10.1007/s11709-019-0575-x

摘要： Based on engineering practices of four typical traffic immersed tunnels built in China, this paper details the features of the four dominant foundation treatment methods for immersed tunnel construction: pile foundation, sand flow foundation, grouting foundation, and gravel bedding foundation. Subsoil stress time-history of different method are specified first, plus a summary of settlement assessment method for foundation quality control. Further, a comprehensive comparison of settlement and cost of these four foundation treatment methods is conducted to highlights the specific merits, disadvantages and conditions encountered in each foundation treatment method, based on real projects information. The findings of this article could henceforth be applied to foundation treatment work in immersed tube tunnel construction.

关键词： foundation treatment method immersed tunnel subsoil stress settlement

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沉管隧道基础灌砂模拟试验

郑爱元,谭忠盛,李治国

《中国工程科学》 2009年第11卷第7期页码 81-85

摘要：

基于相似理论与模拟试验，对沉管隧道基础灌砂的主要参数进行了研究；重点介绍了模拟试验的模型设计、试验流程、试验重点注意事项与试验技术要求，通过试验取得了所需的第一手数据，在对试验成果进行总结分析的基础上，对灌砂施工的主要参数进行了验证分析，其成果可为后续沉管隧道的基础灌砂施工提供参考与借鉴。

关键词：沉管隧道基础灌砂模拟试验

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Natural convection heat transfer of water in a horizontal circular gap

SU Guanghui, WU Yingwei, Kenichiro Sugiyama

《能源前沿（英文）》 2007年第1卷第2期页码 167-173 doi: 10.1007/s11708-007-0021-y

摘要： An experimental study on the natural convection heat transfer on a horizontal downward facing heated surface in a water gap was carried out under atmospheric pressure conditions. A total of 700 experimental data points were correlated using Rayleigh versus Nusselt number in various forms, based on different independent variables. The effects of different characteristic lengths and film temperatures were discussed. The results show that the buoyancy force acts as a resistance force for natural convection heat transfer on a downward facing horizontal heated surface in a confined space. For the estimation of the natural convection heat transfer under the present conditions, empirical correlations in which Nusselt number is expressed as a function of the Rayleigh number, or both Rayleigh and Prandtl numbers, may be used. When it is accurately predicted, the Nusselt number is expressed as a function of the Rayleigh and Prandtl numbers, as well as the gap width-to-heated surface diameter ratio; and uses the temperature difference between the heated surface and the ambient fluid in the definition of Rayleigh number. The characteristic length is the gap size and the film temperature is the average fluid temperature.

关键词： function diameter different independent different characteristic horizontal downward

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Numerical simulation of liquid falling film on horizontal circular tubes

Fengdan SUN, Songlin XU, Yongchuan GAO

《化学科学与工程前沿（英文）》 2012年第6卷第3期页码 322-328 doi: 10.1007/s11705-012-1296-z

摘要： The objective of this study is to investigate numerically the flow characteristics of falling film on horizontal circular tubes. Numerical simulations are performed using FLUENT for 2D configurations with one and two cylinders. The volume of fluid method is used to track the motion of liquid falling film and the gas-liquid interface. The effect of flow characteristics on heat and transfer coefficient may be remarkable, although it has been neglected in previous studies. The velocity distribution and the film thickness characteristics on the top tube, some special flow characteristics on the bottom tube, intertube flow modes and effect of liquid feeder height on flow characteristics have been studied. Our simulations indicate that 1) the velocity distributions of the upper and lower parts of the tube are not strictly symmetric and non-uniform, 2) the film thickness depends on flow rate and angular distributions, 3) the flow characteristics of the top tube are different from those of the bottom tube, 4) three principal and two intermediate transition modes are distinguished, and 5) the liquid feed height plays an important role on the formation of falling film. The numerical results are in a good agreement with the theoretical values by the Nusselt model and the reported results.

关键词： falling film horizontal tube flow characteristics film thickness liquid feeder height

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水下隧道沉管法设计与施工关键技术

杜朝伟,王秀英

《中国工程科学》 2009年第11卷第7期页码 76-80

摘要：

结合国内已建成的沉管隧道对沉管法施工干坞方案比选、管段及接头防水设计进行了探讨分析，对沉管法施工的关键技术如管段制作、管节浮运、沉放及水下对接和基础处理方法进行了归纳。

关键词：沉管隧道方案比选防水设计施工技术

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Numerical analysis of bearing behaviors of single batter piles under horizontal loads in various directions

《结构与土木工程前沿（英文）》 2023年第17卷第2期页码 224-237 doi: 10.1007/s11709-022-0914-1

摘要： The horizontal bearing behavior of a single batter pile (SBP) is vital to its application in practical engineering; however, the horizontal responses of SBPs change with the directions of horizontal loads, and this phenomenon is rarely investigated. Therefore, the directional differences in the horizontal bearing behaviors of SBPs are investigated in this study. Four model tests are conducted to preliminarily examine the effects of the skew angle of horizontal loads on the horizontal bearing capacities and distributions of the bending moments of the SBPs. Subsequently, the differences in the responses of the SBPs under horizontal loads in various directions at full scale are analyzed comprehensively via finite-element (FE) analysis. The effects of the skew angle on SBP-soil interaction are discussed. Moreover, an empirical design method is proposed based on the FE analysis results to predict the bearing ratios of SBPs in medium-dense and dense sand while considering the effects of the skew angle, batter angle, and pile diameter. The method is confirmed to be effective, as confirmed by the close agreement between the predicting results with the model test (reported in this study) and centrifuge model test results (reported in the literature).

关键词： single batter pile skew horizontal load model test finite-element analysis empirical design method

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Experimental study on shear behavior of reinforced concrete beams with web horizontal reinforcement

Dong XU,Yu ZHAO,Chao LIU

《结构与土木工程前沿（英文）》 2014年第8卷第4期页码 325-336 doi: 10.1007/s11709-014-0080-1

摘要： In determining the shear capacity of reinforced concrete beams, current codes do not provide any calculation method to evaluate the influence of web horizontal reinforcement, although they exist as structural reinforcements (or skin reinforcement). The present paper comprises results of 11 reinforced concrete beams in an effort to investigate the influence of web horizontal reinforcement on the shear behavior of reinforced concrete beams. The primary design variables are the shear-span-depth ratio, different reinforcement ratio of stirrups and web horizontal reinforcement. Influence of web horizontal reinforcement on crack patterns and failure mode was studied. It was found that web horizontal reinforcement can increase the shear capacity of the beams and restrain growth of inclined cracks effectively. Test results are very valuable, as very few references of shear tests can be found focusing on the effect of web horizontal reinforcement on the shear capacity of the beams.

关键词： reinforced concrete beam shear strength web horizontal reinforcement experiments

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Optimization model for rotor blades of horizontal axis wind turbines

LIU Xiong, CHEN Yan, YE Zhiquan

《机械工程前沿（英文）》 2007年第2卷第4期页码 483-488 doi: 10.1007/s11465-007-0084-9

摘要： This paper presents an optimization model for rotor blades of horizontal axis wind turbines. The model refers to the wind speed distribution function on the specific wind site, with an objective to satisfy the maximum annual energy output. To speed up the search process and guarantee a global optimal result, the extended compact genetic algorithm (ECGA) is used to carry out the search process. Compared with the simple genetic algorithm, ECGA runs much faster and can get more accurate results with a much smaller population size and fewer function evaluations. Using the developed optimization program, blades of a 1.3 MW stall-regulated wind turbine are designed. Compared with the existing blades, the designed blades have obviously better aerodynamic performance.

关键词： population extended algorithm developed optimization accurate

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Numerical simulation on flow of ice slurry in horizontal straight tube

Shengchun LIU,Ming SONG,Ling HAO,Pengxiao WANG

《能源前沿（英文）》 2021年第15卷第1期页码 201-207 doi: 10.1007/s11708-017-0451-0

摘要： Numerical simulation on flow of ice slurry in horizontal straight tubes was conducted in this paper to improve its transportation characteristics and application. This paper determined the influence of the diameter and length of tubes, the ice packing factors (IPF) and the flow velocity of ice slurry on pressure loss by using numerical simulation, based on two-phase flow and the granular dynamic theory. Furthermore, it was found that the deviation between the simulation results and experimental data could be reduced from 20% to 5% by adjusting the viscosity which was reflected by velocity. This confirmed the reliability of the simulation model. Thus, two mathematical correlations between viscosity and flow velocity were developed eventually. It could also be concluded that future rheological model of ice slurry should be considered in three sections clarified by the flow velocity, which determined the fundamental difference from single-phase fluid.

关键词： ice slurry horizontal tubes numerical simulation pressure drop viscosity model

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β-粒子在穿越铜狭缝中的横向台阶分布

朱永强,郝建宇

《中国工程科学》 2008年第10卷第8期页码 81-86

摘要：

文章研究了电子高速运动时所产生的横向振动。实验方法是利用半圆聚焦β-谱仪上90Sr源β-粒子在不同磁场下对于相同弯曲半径下β-粒子具有不同的能量和动量的特性，研究这些β-粒子在通过不同宽度的铜狭缝（厚8 mm）时的粒子数n和铜狭缝宽度δ的函数关系，发现不管β-粒子具有什么能量和动量，都具有横向运动的趋势和在铜狭缝中出现了台阶分布。其原因可能是β-粒子本身具有横向振幅A和周围真空起伏能量的相互作用。

关键词： β-粒子的横向振动铜狭缝宽度横向台阶分布

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Theoretical prediction and validation of global horizontal solar irradiance for a tropical climate in

Sivasankari SUNDARAM,Jakka SARAT CHANDRA BABU

《能源前沿（英文）》 2015年第9卷第3期页码 311-321 doi: 10.1007/s11708-015-0369-3

摘要： This paper aims to propose monthly models responsible for the theoretical evaluation of the global horizontal irradiance of a tropical region in India which is Sivagangai situated in Tamilnadu. The actual measured global horizontal irradiance hails from a 5 MW solar power plant station located at Sivagangai in Tamilnadu. The data were monitored from May 2011 to April 2013. The theoretical assessment was conducted differently by employing a programming platform called Microsoft Visual Basic 2010 Express. A graphical user interface was created using Visual Basic 2010 Express, which provided the evaluation of empirical parameters for model formulation such as daily sunshine duration ( ), maximum possible sunshine hour duration ( ), extra terrestrial horizontal global irradiance ( ) and extra terrestrial direct normal irradiance ( ). The proposed regression models were validated by the significance of statistical indicators such as mean bias error, root mean square error and mean percentage error from the predicted and the actual values for the region considered. Comparison was made between the proposed monthly models and the existing normalized models for global horizontal irradiance evaluation.

关键词： global horizontal irradiance (GHI) mean bias error root mean square error mean percentage error coefficient of regression Visual Basic 2010 Express

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Experimental study on combined buoyant-thermocapillary flow along with rising liquid film on the surface of a horizontal

Manuel J. GOMES, Ning MEI

《能源前沿（英文）》 2020年第14卷第1期页码 114-126 doi: 10.1007/s11708-017-0483-5

摘要： Temperature distribution and variation with time has been considered in the analysis of the influences of the initial level of immersion of a horizontal metallic mesh tube in the liquid on combined buoyant and thermo-capillary flow. The combined flow occurs along with the rising liquid film flow on the surface of a horizontal metallic mesh tube. Three different levels of immersion of the metallic mesh tube in the liquid have been tested. Experiments of 60 min in duration have been performed using a heating metallic tube with a diameter of 25 mm and a length of 110 mm, sealed outside with a metallic mesh of 178 mm by 178 mm, and distilled water. These reveal two distinct flow patterns. Thermocouples and infrared thermal imager are utilized to measure the temperature. The level of the liquid free surface relative to the lower edge of the tube is measured as angle . The results show that for a smaller angle, or a low level of immersion, with a relatively low heating power, it is possible to near fully combine the upwards buoyant flow with the rising liquid film flow. In this case, the liquid is heated only in the vicinity of the tube, while the liquid away from the flow region experiences small changes in temperature and the system approaches steady conditions. For larger angles, or higher levels of immersion, a different flow pattern is noticed on the liquid free surface and identified as the thermo-capillary (Marangoni) flow. The rising liquid film is also present. The higher levels of immersion cause a high temperature gradient in the liquid free surface region and promote thermal stratification; therefore the system could not approach steady conditions.

关键词： rising liquid film combined flow thermo-capillary flow buoyant flow metallic mesh tube horizontal tube