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| 1 | An improved large eddy simulation of two-phase flows in a pump impeller显示文摘用动态秒顺序 sub-grid-scale (SGS ) 的改进大旋涡模拟压力模型被开发了为稠密的狂暴的粒子液体的管理方程建模在一个旋转坐标系统的二阶段的流动,和连续性被一个团加权的方法保存解决过滤管理方程。在当前的秒顺序 SGS 模型, SGS 压力是解决的紧张率和旋转率张肌的功能,并且模型参数从维的一致性和紧张率和旋转率张肌的 invariants 被获得。在数字计算,有限的卷方法习惯于 discretize 有一个蹒跚的格子系统的管理方程。SIMPLEC 算法被申请管理方程的 discretized 的答案。适合身体的坐标被用来在复杂几何学模仿二阶段的流动。最后秒顺序动态 SGS 模型成功地被使用模仿稠密的狂暴的粒子液体在离心的 impeller 的二阶段的流动。预言的压力和速度分布在对试验性的结果的好同意。 | Xuelin Tang Fujun Wang Yulin Wu | 2007 | Acta Mechanica Sinica2007，23，6： | 10 |
| 2 | A highly conductive and stretchable wearable liquid metal electronic skin for long-term conformable health monitoring显示文摘Conventional rigid electronics are usually unconformable with soft skins and tend to fail in accurate physiological monitoring and precise treatment. Electronic skins(e-Skins) made by conductive and stretchable materials offer mechanical compliance for fabricating flexible and conformable wearables. Compared to common organic or inorganic conductive materials, gallium-based liquid metals alone own superior conductivity and compliance. Here, we demonstrate a highly conductive and stretchable electronic skin with liquid metal circuits(LMCs) embedded in silicone rubber film, which are functionalized for physiological signals monitoring. Through the designs of serpentine structure, LMCs maintained good electrical conductivity and functionality under over 100% strain. Also, a wearable electrocardiogram(ECG) recording device was fabricated and tested. The device was able to acquire steady signals during real-time measurement of physical activities. The proposed liquid metal e-Skin can be further extended to conformable bio-integrated healthcare devices and intelligent health monitoring networks. | GUO Rui WANG XueLin YU WenZhuo TANG JianBo LIU Jing | 2018 | Science China(Technological Sciences)2018，61，7： | 10 |
| 3 | Numerical Simulation of Pressure Fluctuations in a Large Francis Turbine Runner显示文摘The pressure fluctuation caused by unsteady flow in runner is one of the main reasons of vibration for a large Francis hydraulic turbine. It directly affects the steady operation of the hydraulic turbine unit. The existing research of the pressure fluctuation in hydraulic turbine mainly focuses on the unsteady flow in draft tube. Accurate distribution of pressure fluctuations inside a runner is not very clear. In this paper, the numerical method for predicting the pressure fluctuations in runner is investigated and the numerical simulation is performed for a large Francis hydraulic turbine. It is proved that the combination of shear-stress transport(SST) k-w turbulence model and pressure-implicit with splitting of operators(PISO) algorithm could give more reliable prediction of pressure fluctuations in runner. The frequencies of pressure fluctuations in runner are affected by the flow in guide vane and the flow in draft tube. The first dominant frequency is significantly determined by the flow in draft tube, especially at part load condition. This frequency is approximately equal to one-third of the runner rotating frequency. The evident second dominant frequency is exactly equal to the guide vane passing frequency. The peak-to-peak amplitudes of pressure fluctuations in runner at small guide vane open angle are larger than that at large open angle at the same operating head. The amplitudes at points on blade pressure surface are generally greater than that on suction surface. The research results could be used to direct the hydraulic design and operation stability improvement of a large Francis hydraulic turbine. | WANG Fujun LIAO Cuilin TANG Xuelin | 2012 | Chinese Journal of Mechanical Engineering2012，25，6： | 9 |
| 4 | A lattice Boltzmann model coupled with a Large Eddy Simulation model for flows around a groyne显示文摘This present paper proposes a two-dimensional lattice Boltzmann model coupled with a Large Eddy Simulation (LES) model and applies it to flows around a non-submerged groyne in a channel. The LES of shallow water equations is efficiently performed using the Lattice Boltzmann Method (LBM) and the turbulence can be taken into account in conjunction with the Smagorinsky Sub-Grid Stress (SGS) model. The bounce-back scheme of the non-equilibrium part of the distribution function is used to determine the unknown distribution functions at inflow boundary, the zero gradient of the distribution function is set normal to outflow boundary to obtain the unknown distribution functions here and the bounce-back scheme, which states that an incoming particle towards the boundary is bounced back into fluid, is applied to the solid wall to ensure non-slip boundary conditions. The initial flow field is defined firstly and then is used to calculate the local equilibrium distributions as initial conditions of the distribution functions. These coupled models successfully predict the flow characteristics, such as circulating flow, velocity and water depth distributions. The comparisons between the simulated results and the experimental data show that the model scheme has the capacity to solve the complex flows in shallow water with reasonable accuracy and reliability. | Xin YU Xuelin TANG Wuchang WANG Fujun WANG Zhicong CHEN Xiaoyan SHI | 2010 | International Journal of Sediment Research2010，25，3： | 4 |
| 5 | EXPERIMENTAL INVESTIGATIONS AND NUMERICAL SIMULATIONS OF REDUCING SECONDARY FLOWS AROUND A SPUR DIKE显示文摘To better understand the flow patterns near Jiuling Hill in the approach navigation channel of the Three Gorges Project and to improve the navigation channel, a physical flume model was constructed with a non-submerged spur dike placed as a barrier. An approach of sucking a small amount of water from the upper flume at the convex side of the spur dike and spouting it out again into the lower flume at the downstream side of the spur dike, so-called “sucking-spouting” water method, was proposed to improve navigational conditions. The flows around the spur dike for this method are experimentally investigated, and are compared to those in the no “sucking-spouting” water case. Based on the rigid lid assumption and a Dynamic Smagorinsky Model, all the vortex flows around the spur dike are numerically simulated, and the data are analyzed systematically. By applying “sucking-spouting” method, the recirculation zone caused by the spur dike reduced greatly and the transverse velocity decreased. At the same time, the flow behind the spur dike is much more complex, and materials and momentum substantially exchange between the dead zone and the main flow because of spouting action. The finite volume method is used to discretize the governing equations together with a staggered grid system, where the second-order difference is applied for the diffusion terms and the source terms while the upwind difference QUICK is used for the convection terms. The computational results are in fairly good agreement with the experimental data. | Xuelin TANG Xiang DING Zhicong CHEN Wenlong WANG | 2006 | International Journal of Sediment Research2006，21，2： | 2 |
| 6 | Numerical research on lid-driven cavity flows using a three-dimensional lattice Boltzmann model on non-uniform meshes显示文摘A lattice Boltzmann model combined with curvilinear coordinate is proposed for lid-driven cavity three-dimensional (3D) flows. For particle velocity distribution, the particle collision process is performed in physical domain, and the particle streaming process is carried out in the corresponding computational domain, which is transferred from the physical domain using interpolation method. For the interpolation calculation, a second-order upwind interpolation method is adopted on internal lattice nodes in flow fields while a second-order central interpolation algorithm is employed at neighbor-boundary lattice nodes. Then the above-mentioned model and algorithms are used to numerically simulate the 3D flows in the lid-driven cavity at Reynolds numbers of 100, 400 and 1000 on non-uniform meshes. Various vortices on the x-y, y-z and x-z symmetrical planes are successfully predicted, and their changes in position with the Reynolds number increasing are obtained. The velocity profiles of u component along the vertical centerline and w component along the horizontal centerline are both in good agreement with the data in literature and the calculated results on uniform meshes. Besides, the velocity vector distributions on various cross sections in lid-driven cavity predicted on non-uniform meshes are compared with those simulated on uniform meshes and those in the literature. All the comparisons and validations show that the 3D lattice Boltzmann model and all the numerical algorithms on non-uniform meshes are accurate and reliable to predict effectively flow fields. | TANG XueLin SU YanWen WANG FuJun LI LinWei | 2013 | Science China(Technological Sciences)2013，56，9： | 1 |
| 7 | Numerical investigations of vortex flows and vortex suppression schemes in a large pumping-station sump显示文摘 | Tang Xuelin Wang Fujun Li Yaojun | 2011 | Proceedings of the lnstitution of Mechanical Engineers2011，225，6： | 1 |
| 8 | Damping of aluminum-matrix composite reinforced by carbon nanotube:Multiscale modeling and characteristics显示文摘It is a crucial requirement for structure-damping materials to attain both stiffness and damping;unfortunately,the two properties are usually mutually exclusive.This study interestingly demonstrates that introducing Ni atoms into the interface of carbon nanotube(CNT)reinforced aluminum-matrix composites can defeat the conflict of stiffness versus damping.This originates from the gradient variation of the modulus and energy dissipation in the effective interfacial zone.The rule of mixture is modified by taking the interface contribution into account,and a gradient damping model is proposed to account for the contribution of the interface energy dissipation.Molecular dynamics simulations confirm that the proposed multiscale modulus and damping models can describe the elastic modulus and damping behavior of the composites with different volume fractions and different diameters of CNTS.The gradient interface slip caused by the lattice mismatches and misfit dislocations between Ni-coated CNT and aluminum is one of the pathways for achieving unprecedented levels of the product of stiffness and damping. | WANG Fei LI Li TANG HaiShan WANG XueLin HU YuJin | 2023 | Science China(Technological Sciences)2023，66，4： | 1 |
| 9 | Nu- merical investigation of vortex flows and vortex suppres- sion schemes in a large pumping-station sump 显示文摘 | TANG Xuelin WANG Fujun LI Yanjun | 2011 | Jour- nal of mechanical engineering science2011，225，6： | 1 |
| 10 | Numerical investigation on cavitating flows with thermodynamic effects in a diffuser-type centrifugal pump显示文摘 | Tang Xuelin Bian Liyuan Wang Fujun | 2013 | Journal of Mechanical Science and Technology2013，27，6： | 1 |
| 11 | Comparison between Plane and Stereo Block Adjustment for ZY-3 Satellite Images显示文摘Block adjustment for satellite images cannot be solved with weak convergence geometric conditions,therefore a plane block adjustment method to improve the targeting precision of images is proposed utilizing DEM as height constraint plane block adjustment method.First,a rational function model with affine transformation is selected as the mathematical model of the satellite image plane block adjustment.Second,to update the ground coordinates of tie points(TPs),the plane coordinates of TPs are only solved in the adjustment process.Elevation values are obtained by using DEM interpolation.Finally,the plane coordinates of all TPs and orientation parameters of all satellite images are solved through plane block adjustment with a few ground control points ZY-3 nadir images for two regions are tested for plane block adjustment while ZY-3 forward-nadir-back images of the same two regions are tested for stereo block adjustment.A comparison indicates that almost the same accuracy can be obtained with plane block adjustment support using a 1∶50 000 DEM and stereo block adjustment for ZY-3 images.For ZY-3 nadir images,almost no loss of plane block adjustment accuracy occurred when global DEM with 1 km grid and SRTM with 90 m grid replaced the 1∶50 000 DEM as elevation control,.Test results demonstrate the effectiveness and feasibility of the plane block adjustment method. | Taoyang WANG Guo ZHANG Deren LI Wanshou JIANG Xinming TANG Xuelin LIU | 2018 | Journal of Geodesy and Geoinformation Science2018，1，1： | 1 |
| 12 | Vibration analysis of fluid- structure interaction in water hammer based on transfer matrix method显示文摘In consideration of the problem that the effect of conduit structure on water hammer has been ignored in the classical theory,the Poisson coupling between the fluid and the pipeline was studied and a fourteen-equation mathematical model of fluid-structure interaction(FSI)was developed.Then,the transfer matrix method(TMM)was used to calculate the modal frequency,modal shape and frequency response.The results were compared with that in experiment to verify the correctness of the TMM and the results show that the fluid-structure coupling has a greater impact on the modal frequencies than the modal shape.Finally,the influence on the response spectrum of different damping ratios was studied and the results show that the natural frequency under different damping ratios has changed little but there is a big difference for the pressure spectrum.With the decreasing of damping ratio,the damping of the system on frequency spectrum is more and more significant and the dispersion and dissipation is more and more apparent.Therefore the appropriate damping ratio should be selected to minimize the effects of the vibration of the FSI.The results provide references for the theory research of FSI in the transient process. | GAO Hui TANG Xuelin | 2016 | 排灌机械工程学报2016，34，6： | 1 |
| 13 | EARTHQUAKE FOCAL MECHANISM AND ITS TECTONIC SIGNIFICANCE ALONG THE TWO SIDES OF THE RED RIVER FAULT ZONE显示文摘The Red River Fault Zone is a gigantic slide-slip fault zone extending up to 1000km from Tibet to SouthChina Sea. It has been divided into the north, central and south segments according to the difference of thegeometry, kinetics, and seismicity on the land, but according to the contacted relationship between the old pre-Cenozoic block in Indochina Peninsula and the South China block, the Red River Fault Zone was divided into two parts extending from land to ocean, the north and south segments. Since the Tertiary, the Red River Fault Zone suffered first the sinistral movement and then the dextral movement. The activities of the north and the south segments were different. Based on the analysis of earthquakes and focal mechanism solutions,earthquakes with the focus depths of 0-33km are distributed over the whole region and more deep earthquakes are distributed on the northeastern sides of the Red River fault. Types of faulting activities are the thrust in the northwest, the normal in the north and the strike-slip in the south, with the odd type, viz. the transition type, in the other region. These show the Red River Fault Zone and its adjacent region suffered the extruding force in NNW direction and the normal stress in NEE direction and it makes the fault in the region extrude-thrust,horizontal strike-slip and extensional normal movement. | ZHU Junjiang ZHAN Wenhuan QIU Xuelin XU Huilong TANG Cheng | 2004 | Geotectonica et Metallogenia2004，28，1： | 0 |
| 14 | Experimental Investigation of Flow Patterns in a Pump Intake with Different CWL(Critical Water Level)and Back-Wall Clearance显示文摘In this study,influence of back-wall clearance,CWL(Critical Water Level)and air content in water on flow patterns in a pump intake has been investigated experimentally and theoretically for different cases.The statistical data show that CWL for a two-phase flow is lower than that in the case of a single-phase flow at a relatively low flow rate,and as the flow rate increases,this trend turns out to be completely reversed.Fine experimental data obtained under conditions of subcritical,critical and supercritical flow rates have revealed that the larger the back-wall clearance is,the more vortices exist and the higher the vorticity of free-surface vortices is.For the smallest back-wall clearance,the flow coming through the inlet occupies most space under the pipe bell,and both this flow and the inflow coming from the back wall are asymmetric relative to a certain vertical line other than the axis.For the larger and the largest back-wall clearances,the flows coming from the inlet and from the back wall are almost symmetrical relative to the vertical axis of the pipe bell.The velocity distributions on two PIV measurement lines for different back-wall clearance magnitudes indicate that the smallest back-wall clearance influences the flow around the pipe bell. | GUO Miao TANG Xuelin LI Xiaoqin WANG Fujun | 2021 | Journal of Thermal Science2021，30，6： | 0 |
| 15 | Progress in efficient doping of Al-rich AlGaN显示文摘The development of semiconductors is always accompanied by the progress in controllable doping techniques.Taking AlGaN-based ultraviolet(UV)emitters as an example,despite a peak wall-plug efficiency of 15.3%at the wavelength of 275 nm,there is still a huge gap in comparison with GaN-based visible light-emitting diodes(LEDs),mainly attributed to the inefficient doping of AlGaN with increase of the Al composition.First,p-doping of Al-rich AlGaN is a long-standing challenge and the low hole concentration seriously restricts the carrier injection efficiency.Although p-GaN cladding layers are widely adopted as a compromise,the high injection barrier of holes as well as the inevitable loss of light extraction cannot be neglected.While in terms of n-doping the main issue is the degradation of the electrical property when the Al composition exceeds 80%,resulting in a low electrical efficiency in sub-250 nm UV-LEDs.This review summarizes the recent advances and outlines the major challenges in the efficient doping of Al-rich AlGaN,meanwhile the corresponding approaches pursued to overcome the doping issues are discussed in detail. | Jiaming Wang Fujun Xu Lisheng Zhang Jing Lang Xuzhou Fang Ziyao Zhang Xueqi Guo Chen Ji Chengzhi Ji Fuyun Tan Xuelin Yang Xiangning Kang Zhixin Qin Ning Tang Xinqiang Wang Weikun Ge Bo Shen | 2024 | Journal of Semiconductors2024，45，2： | 0 |
| 16 | Applications of Three-Dimensional LBM-LES Combined Model for Pump Intakes显示文摘Lattice Boltzmannmodel(LBM)in conjunction with an accurate Large Eddy Simulation(LES)technology was proposed to simulate various vortical structures and their evolutions in open pump intakes.The strain rate tensor in the LES model is locally calculated by means of non-equilibrium moments based on Chapman-Enskog expansion,and bounce-back scheme was used for non-slip condition on solid walls and reflection scheme for free surface.The presentedmodel was applied to investigate free-surface and wall-attached vortices for different water levels and flow rate.The vortex position,shapes and vorticities were predicted successfully under three flowing cases(i.e.critical water level(CWL),lower water level,lower flow rate),and the numerical velocity and streamline distribution were analyzed systematically.For CWL based on Froude number considering open channel flows,the shape and the location of various dynamic vortices were captured.Compare to the experimental results of CWL,more vortices were predicted for lower water level,and less vortices were observed for lower flow rate.The predicted velocities and vortex locations are in good agreement with the experimental of a small physical model.The comparisons demonstrated the feasibility and stability of above-mentioned model and numerical method in predicting vortex flows inside open pump intakes. | Miao Guo Xuelin Tang Yanwen Su Xiaoqin Li Fujun Wang | 2018 | Communications in Computational Physics2018，24，6： | 0 |
| 17 | Analytical approach for sheet flow transport in purely acceleration-skewed oscillatory flow显示文摘An instantaneous analytical approach is developed to predict sheet flow transport in purely accelerationskewed oscillatory flow. The approach is derived from exponential approximations of velocity and concentration profiles above a mobile seabed, and it particularly considers factors of phase lead; phase lag(i.e. phase residual and phase shift); acceleration modification; and asymmetries in shear stress,roughness height, and boundary layer development. The approach can predict net boundary layer flow above a mobile seabed, and can revert to the classical bedload model. Instantaneous and net sediment transport rates are studied using the approach. The instantaneous sediment transport rate in an onshore flow stage can be approximated by a power function of velocity in which the exponent is confirmed to range between 1 and 5 with a decrease in the phase residual. The net sediment transport rate predicted using the approach is validated using a considerable amount of measured data, and compared with existing instantaneous and half-period type models that consider the phase lag or acceleration modification. For the net sediment transport rate in purely acceleration-skewed oscillatory flow, the phase residual is less important than the acceleration-skewed boundary layer difference between onshore and offshore acceleration stages. | Xin Chen Fujun Wang Xuelin Tang | 2018 | International Journal of Sediment Research2018，33，3： | 0 |
| 18 | The levels of osteopontin in human milk of Chinese mothers and its associations with maternal body composition显示文摘Objective:This study explored the content and change trend of osteopontin(OPN)in breast milk and analyzed the relationship between OPN in breast milk and maternal body composition.Methods:Breast-feeding mothers were recruited in Xinhua Hospital to collect breast milk and provide pertinent information.The content of OPN in breast milk was determined by enzyme-linked immunosorbent assay(ELISA).Determination of protein content in human milk was performed via the BCA method.The maternal body composition was determined by the bioelectrical impedance method.Serum glucocorticoid receptorα,adiponectin,insulin,and leptin were determined by ELISA.SPSS 25 was used for statistical analysis.Results:In the longitudinal cohort,106 mothers provided 318 milk samples at different lactation periods.The results indicate that the OPN showed dynamic changes.OPN levels were(343.2±163.5)mg/L during 1-14 days postpartum,(228.4±121.5)mg/L during 2-4 months postpartum,and(204.8±100.6)mg/L during 5-7 months postpartum.The content of OPN was very high in the first 1-14 days postpartum and then decreased.Compared with early postpartum milk,the OPN content of mature milk showed a significant relationship with maternal weight-related parameters.Additional body composition analysis was performed in 88 women at the mature milk phase.The results show that the OPN in milk is related to the mother’s body composition,especially the content of skeletal muscle mass,but not to relevant humoral factors.Conclusions:The levels of OPN in human milk of Chinese mothers showed dynamic changes with the extension of lactation time.The OPN in human milk was related to the mother’s body composition but not related to related humoral factors. | Huijuan Ruan Qingya Tang Xuan Zhao Yajie Zhang Xuelin Zhao Yi Xiang Wei Geng Yi Feng Wei Cai | 2022 | Food Science and Human Wellness2022，11，5： | 0 |
| 19 | The H3K9me2-binding protein AGDP3 limits DNA methylation and transcriptional gene silencing in Arabidopsis显示文摘DNA methylation,a conserved epigenetic mark,is critical for tuning temporal and spatial gene expression.The Arabidopsis thaliana DNA glycosylase/lyase REPRESSOR OF SILENCING 1(ROS1)initiates active DNA demethylation and is required to prevent DNA hypermethylation at thousands of genomic loci.However,how ROS1 is recruited to specific loci is not well understood.Here,we report the discovery of Arabidopsis AGENET Domain Containing Protein 3(AGDP3)as a cellular factor that is required to prevent gene silencing and DNA hypermethylation.AGDP3 binds to H3K9me2 marks in its target DNA via its AGD12 cassette.Analysis of the crystal structure of the AGD12 cassette of AGDP3 in complex with an H3K9me2 peptide revealed that dimethylated H3 K9 and unmodified H3 K4 are specifically anchored into two different surface pockets.A histidine residue located in the methyllysine binding aromatic cage provides AGDP3 with pH-dependent H3K9me2 binding capacity.Our results uncover a molecular mechanism for the regulation of DNA demethylation by the gene silencing mark H3K9me2. | Xuelin Zhou Mengwei Wei Wenfeng Nie Yue Xi Li Peng Qijie Zheng Kai Tang Viswanathan Satheesh Yuhua Wang Jinyan Luo Xuan Du Rui Liu Zhenlin Yang Honggui La Yingli Zhong Yu Yang Jian-Kang Zhu Jiamu Du Mingguang Lei | 2022 | Journal of Integrative Plant Biology2022，64，12： | 0 |
| 20 | Longitudinal changes in body weight of breastfeeding mothers in the first year after delivery and its relationship with human milk composition:a combined longitudinal and cross-sectional cohort study显示文摘Objective:Postpartum weight retention(PPWR)is a common problem among women after childbirth.The main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term follow-up and preliminarily explore the relationship between maternal body weight and human milk composition,including macronutrients,leptin,and adiponectin.Methods:The study included a longitudinal cohort(122 mothers),and a cross-sectional cohort(37 mothers).The human milk,maternal weight,and dietary surveys were collected in the longitudinal cohort at different follow-up time points(1-14 days postpartum,2-4 months postpartum,5-7 months postpartum,and 12-17 months postpartum).The maternal body weight was analyzed using the responses in the survey questionnaires.A milk analyzer based on the mid-infrared spectroscopy(MIRS)was used to determine milk composition,and nutrition analysis software evaluated dietary intakes.In the cross-sectional cohort,participating mothers were asked to provide blood and human milk samples and pertinent information related to maternal body composition.Maternal body composition was measured by bioelectrical impedance analysis(BIA),while ELISA analyzed leptin and adiponectin in milk and serum.Results:At 5-7 months postpartum,the PPWR of breastfeeding mothers was(2.46±3.59)kg.At 12-17 months postpartum,the PPWR was(0.98±4.06)kg.PPWR was found to be negatively correlated with milk fat content within 14 days postpartum and positively correlated at 2-4 months postpartum.In addition,the maternal weight and body muscle mass were positively correlated with leptin and adiponectin in milk.Plasma leptin was positively correlated with the mother’s body weight,body mass index(BMI),FAT percentage,and body fat mass,while plasma adiponectin did not correlate with any parameter.The results also indicate that the PPWR did not correlate with leptin and adiponectin in plasma or milk.Conclusions:Breastfeeding mothers may retain considerable weight gain one year after delivery.Human milk composition may be related to changes in maternal body weight.Leptin and adiponectin in breast milk and leptin in plasma are associated with the maternal body composition.This study supports the notion that maternal nutritional status may affect offspring health through lactation,and future research should focus on exploring weight management of postpartum mothers. | Huijuan Ruan Yajie Zhang Qingya Tang Xuan Zhao Xuelin Zhao Yi Xiang Wei Geng Yi Feng Wei Cai | 2024 | Food Science and Human Wellness2024，13，1： | 0 |
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