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Chinese Journal of Chemical Engineering 2002年第2期10卷 142-148页

作者：周力行杨玟廉春英 l.s.fan D.J.lee Department of Engineering Mechanics Tsinghua University Beijing 100084 China Department of Chemical Engineering The Ohio State University USA

A full second-order moment (FsM) model and an algebraic stress (AsM) two-phase turbulence modelare proposed and applied to predict turbulent bubble-liquid flows in a 2D rectangular bubble column. Predictiongives the bubble and liquid velocities, bubble volume fraction, bubble and liquid Reynolds stresses and bubble-liquidvelocity correlation. For predicted two-phase velocities and bubble volume fraction there is only slight differencebetween these two models, and the simulation results using both two models are in good agreement with the particleimage velocimetry (PIV) measurements. Although the predicted two-phase Reynolds stresses using the FsM are insomewhat better agreement with the PIV measurements than those predicted using the AsM, the Reynolds stressespredicted using both two models are in general agreement with the experiments. Therefore, it is suggested to usethe AsM two-phase turbulence model in engineering application for saving the computation time.

关键词： second-order moment model two-phase turbulence bubble-liquid flow bubble column

large-eddy simulation of Bubble-liquid Confined Jets

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Chinese Journal of Chemical Engineering 2002年第4期10卷 381-384页

作者：杨玟周力行 l.s.fan Department of Engineering Mechanics Tsinghua University 北京 100084

The large-eddy simulation (lEs) with two-way coupling is used to study bubble-liquid two-phase confined multiple jets discharged into a 2D *** lEs results reveal the large-eddy vortex structures of both liquid flow and bubble motion,the shear-generated and bubble-induced liquid turbulence,and indicate much stronger bubble fluctuation than that of the liquid,the enhancement of liquid turbulence by *** shear and bubble-liquid interaction are important for the liquid turbulence generation in the case studied.

关键词： large-eddy simulation bubble-liquid flow two-phase jet

鼓泡床内气泡-液体两相湍流代数应力模型的数值模拟

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化工学报 2002年第8期53卷 780-786页

作者：周力行杨玟廉春英 l.s.fan D.J.lEE 清华大学工程力学系北京100084 俄亥俄州立大学化学工程系

现有的气泡 -液体两相流动的数值模拟中 ,或者不考虑湍流 ,或者仅仅考虑液体湍流 ,但是直接模拟和PIV测量结果都表明气泡由于尾迹的作用有强烈的湍流脉动 .本文首次推导和封闭了同时模拟气泡湍流脉动和液体湍流脉动的二阶矩输运方程两... 详细信息

现有的气泡 -液体两相流动的数值模拟中 ,或者不考虑湍流 ,或者仅仅考虑液体湍流 ,但是直接模拟和PIV测量结果都表明气泡由于尾迹的作用有强烈的湍流脉动 .本文首次推导和封闭了同时模拟气泡湍流脉动和液体湍流脉动的二阶矩输运方程两相湍流模型 ,并在此基础上建立了代数应力气泡 -液体两相湍流模型 .用代数应力模型模拟了二维矩形断面鼓泡床内气泡 -液体两相流动 .预报结果给出了气泡和液体两相速度场、两相Reynolds应力及湍动能分布和气泡体积分数分布 .模拟结果与PIV测量结果符合很好 ,表明了模型的合理性 .研究结果表明 ,原先静止的液体在气泡因浮力而产生的上升运动的作用下产生回流流动 ,而气泡则只有上升运动 .气泡速度始终大于液体速度 .在床内气泡湍流脉动确实始终很强烈 .液体则由于气泡的作用以及自身速度梯度产生的双重作用而发生湍流脉动 .气泡的脉动显著地大于液体的脉动 .两相湍流脉动都是各向异性的。

关键词：数值模拟鼓泡床气液两相湍流代数应力模型单汽泡动力学

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气泡-液体闭式多股射流的大涡模拟研究

工程热物理学报 2003年第1期24卷 127-130页

作者：杨玟周力行李荣先 l.s.fan 清华大学工程力学系北京100084 Department of Chemical Engineering The Ohio State UniversityColumbusUSA

采用气泡-液体两相流动的欧拉-拉氏大涡模拟,研究了矩形通道内多股射流形成的气泡-液体两相湍流流动,得到了气液两相湍流瞬态结构,产生和发展过程。研究结果发现气泡和液体都有瞬态大涡结构,气泡脉动比液体的强。大涡模拟统计结果给出... 详细信息

采用气泡-液体两相流动的欧拉-拉氏大涡模拟,研究了矩形通道内多股射流形成的气泡-液体两相湍流流动,得到了气液两相湍流瞬态结构,产生和发展过程。研究结果发现气泡和液体都有瞬态大涡结构,气泡脉动比液体的强。大涡模拟统计结果给出了有无气泡两种情况下的液体湍流脉动速度均方根值分布。瞬态和统计结果都表明,气泡增大了液体湍流,液体湍流来源于其自身的剪切产生和气泡的作用。这与二阶矩模型模拟结果定性一致。

关键词：气泡-液体闭式多股射流气液两相射流两相湍流大涡模拟

气泡-液体多股射流二阶矩两相湍流模型的模拟

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工程热物理学报 2002年第2期23卷 231-234页

作者：杨玟周力行李荣先 l.s.fan 清华大学工程力学系北京100084 Department of Chemical Engineering The Ohio state University

本文采用二阶矩两相湍流模型模拟了气泡－液体闭式多股射流。研究结果显示出预报的两相速度、雷诺应力和气泡体积分数分布的合理性，以及在速度较高和剪切较强的情况下，气泡湍流脉动仍然大于液体湍流脉动，气泡增强液体湍流，气液两相... 详细信息

本文采用二阶矩两相湍流模型模拟了气泡－液体闭式多股射流。研究结果显示出预报的两相速度、雷诺应力和气泡体积分数分布的合理性，以及在速度较高和剪切较强的情况下，气泡湍流脉动仍然大于液体湍流脉动，气泡增强液体湍流，气液两相湍流脉动均存在各向异性，而且气泡脉动的各向异性比液体脉动的大等规律。

关键词：两相湍流二阶矩模型数值模拟气泡-液体多股射流速度应力体积脉动

spalling characteristics of high-temperature treated granitic rock at different strain rates

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1280-1288页

作者： l.F.fan Q.H.Yang X.l.Du The Key laboratory of Urban security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing100124China

The dynamic spalling characteristics of rock are important for stability analysis in rock *** paper presented an experimental investigation on the dynamic spalling characteristics of granite with different temperatures and strain rates.A series of dynamic spalling tests with different impact velocities were conducted on thermally treated granite at different *** dynamic spalling strengths of granite with different temperatures and strain rates were determined.A model was proposed to correlate the dynamic spalling strength of granite,high temperature and strain *** results show that the spalling strength of granite decreases with increasing ***,the spalling strength of granite with a higher strain rate is larger than that with a lower strain *** proposed model can describe the relationship among dynamic spalling strength of granite,high temperature and strain rate.

关键词： Dynamic spalling characteristics High temperature strain rate Dynamic loading Granite

Metric and Upper Dimension of Extended Annihilating-Ideal Graphs

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Algebra Colloquium 2024年第2期31卷 221-238页

作者： s.Nithya G.Elavarasi Genghua fan Department of Mathematics St.Xavier's College(Autonomous)Palayamkottai 627002Tamil NaduIndia Afiliated to Manonmaniam sundaranar University Abishekapatti Tirunelveli 627012Tamil NaduIndia PG and Research Department of Mathematics St.Xavier's College(Autonomous)Palayamkottai 627002Tamil NaduIndia Affiliated to Manonmaniam sundaranar University Abishekapatti Tirunelveli 627012Tamil NaduIndia 不详

The metric dimension problem is called navigation problem due to its application to robot navigation in *** this concept has wide applications in motion planning,sonar and loran station,and so *** this paper,we study certain results on the metric dimension,upper dimension and resolving number of extended annihilating-ideal graph EAG(R)associated to a commutative ring R,denoted by dim M(EAG(R)),dim+(EAG(R))and res(EAG(R)),*** we prove the finiteness conditions of dim M(EAG(R))and dim+(EAG(R)).In addition,we characterize dim M(EAG(R)),dim+(EAG(R))and res(EAG(R))for artinian rings and the direct product of rings.

关键词： extended annihilating-ideal graph metric dimension upper dimension resolving number

Material flow analysis and global warming potential assessment of an industrial insect-based bioconversion plant using housefly larvae

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Journal of Environmental sciences 2024年第5期139卷 483-495页

作者： Tao lu fan lü Nanlin liao Honghui Chai Hua Zhang Pinjing He Institute of Waste Treatment and Reclamation Tongji UniversityShanghai 200092China state Key laboratory of Pollution Control and source Reuse Tongji UniversityShanghai 200092China Zhejiang Qihe Ecological Technology Co. Ltd.Hangzhou 310052China

The significant increase in the demand for biomass waste treatment after garbage classification has led to housefly larvae treatment becoming an attractive treatment *** can provide a source of protein while treating biomass waste,which means that nutrients can be returned to the natural food ***,the performance of this technology in terms of its environmental impacts is still unclear,particularly with regards to global warming potential(GWP).This study used a life cycle assessment(lCA)approach to assess a housefly larvae treatment plant with a treatment capacity of 50 tons of biomass waste per *** lCA results showed that the 95% confidence intervals for the GWP in summer and winter were determined to be 24.46-32.81 kg CO_(2) equivalent(CO_(2)-eq)/ton biomass waste and5.37-10.08 kg CO_(2)-eq/ton biomass waste,*** greater GWP value in summer is due to the longer ventilation time and higher ventilation intensity in summer,which consumes more *** main GWP contributions are from(1)electricity needs(accounting for 78.6% of emissions in summer and 70.2%in winter)and(2)product substitution by mature housefly larvae and compost(both summer and winter accounting for 96.8% of carbon reduction).

关键词： Biomass waste Musca domestica Housefly larvae life cycle assessment Global warming potential

seismic response of pile-supported structures considering the coupling of inertial and kinematic interactions in different soil sites

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Frontiers of structural and Civil Engineering 2024年第9期18卷 1350-1361页

作者： Huiling ZHAO fan ZHANG Department of Civil Engineering Shanghai UniversityShanghai 200444China

Dynamic soil−pile−superstructure interaction is crucial for understanding pile behavior in earthquake-prone *** the safety of piles requires determining the seismic bending moment caused by combined inertial and kinematic interactions,which is *** paper addresses this problem through numerical simulations of piles in different soil sites,considering soil *** reveal that the period of the soil site significantly affects the interaction among soil,piles,and *** moments in soft and hard soil sites exceed those in medium soil sites by more than *** modes of piles exhibit distinct characteristics between hard and soft soil *** soil sites exhibit a singular inflection point,while hard soil sites show two inflection *** soft soil sites,pile-soil kinematic interaction gradually increases bending moment from tip to head,with minor influence from superstructure’s inertial *** hard soil sites,significant inertial effects from soil,even surpassing pile-soil kinematic effects near the tip,lead to reversed superposition bending ***’s inertial interaction notably impacts pile head in hard soil sites.A simplified coupling method is proposed using correlation coefficient to represent inertial and kinematic *** findings provide insights into complex seismic interactions among soil,piles,and structures.

关键词： pile seismic response soft soil inertial interaction kinematic interaction

Bi_(2)WO_(6)/AgIns_(2)s-scheme heterojunction:Efficient photodegradation of organic pollutant and toxicity evaluation

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Journal of Materials science & Technology 2024年第3期170卷 200-211页

作者： Yanyan Zhao Xu fan Hongxing Zheng Enzhou liu Jun fan Xuejun Wang College of Biology Pharmacy and Food Engineering Shangluo UniversityShangluo 726000China Qinling-Bashan Mountains Bioresources Comprehensive Development C.I.C. Shaanxi University of TechnologyHanzhong 723001China school of Chemical Engineering Northwest UniversityXi’an 710069China

Constructing of heterojunction was identified as a feasible way to improve photocatalytic activity of *** this work,a n-p type Bi_(2)WO_(6)/AgIns_(2)s-scheme heterojunction was successfully prepared for organic pollutants *** Bi_(2)WO_(6)/AgIns_(2)s-scheme heterojunction exhibited much higher pho-tocatalytic activity towards Rhodamine B(92.24%,expose to visible light for 60 min),norfloxacin(81.73%,expose to visible light for 90 min)and levofloxacin(87.46%,expose to visible light for 90 min)than pure Bi_(2)WO_(6)and pure AgIns_(2).Toxicity analysis indicated the low environmental toxicity of Rhodamine B degradation intermediates for Rye seeds and sudangrass seeds germination and *** study displayed that AgIns_(2)and Bi_(2)WO_(6)work as the primary photocatalyst to form·O_(2)−and ·OH,*** improved photocatalytic activity of the Bi_(2)WO_(6)/AgIns_(2)s-scheme heterojunction was due to the im-proved light response range and intensified carrier separation ***,a s-scheme charge transfer mechanism including multiple charge transfer channels was *** work could provide an effective strategy for organic pollutants degradation in wastewater.

关键词： Photocatalysis s-scheme heterojunction AgIns_(2) Bi_(2)WO_(6) Toxicity experiments