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A GPU-accelerated two-phase flow model for fluid-solid interaction using the sharp interface immersed boundary method

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Journal of Hydrodynamics 2024年第5期36卷 883-897页

作者： Li-ping Ma ji-jian lian Dong-ming Liu State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin300072China School of Civil Engineering Tianjin UniversityTianjin300072China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu610065China

A two-phase flow model accelerated by graphical processing unit(GPU)is developed to solve fluid-solid interaction(FSI)using the sharp-interface immersed boundary method(IBM).This model solves the incompressible Navier-Stokes equations using the projection-based fractional step method in a fixed staggered Cartesian grid system.A volume of fluid(VOF)method with second-order accuracy is employed to trace the free *** represent the intricate surface geometry,the structure is discretized using the unstructured triangle ***,a ray tracing method is employed to classify fluid and solid points.A high-order stable scheme has been introduced to reconstruct the local velocity at interface *** FSI problems,including wave evolution around a breakwater,interaction between a periodic wave train and a moving float,and a 3-D moving object interacting with the free surface,were investigated to validate the accuracy and stability of the proposed *** numerical results are in good agreement with the experimental ***,we evaluated the computational performance of the proposed GPU-based *** GPU-based model achieved a 42.29 times speedup compared with the single-core CPU-based model in the three-dimension ***,the results regarding the time cost of each code section indicate that achieving more significant acceleration is associated with solving the turbulence,advection,and diffusion terms,while solving the pressure Poisson equation(PPE)saves the most ***,the impact of grid number on computational efficiency indicates that as Fluid-solid interaction(FSI)immersed boundary method(IBM)graphical processing unit(GPU)two-phase flow moving rigid bodythe number of grids increases,the GPU-based model outperforms the multi-core CPU-based model.

关键词： Fluid-solid interaction(FSI) immersed boundary method(IBM) graphical processing unit(GPU) two-phase flow moving rigid body

Optimal sensor placement in hydropower house based on improved triaxial effective independence method

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Water Science and Engineering 2012年第3期5卷 329-339页

作者： ji-jian lian Long-jun HE Hai-jun WANG State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University Tianjin 300072 P. R. China

The capacity and size of hydro-generator units are increasing with the rapid development of hydroelectric enterprises, and the vibration of the powerhouse structure has increasingly become a major problem. Field testing is an important method for research on dynamic identification and vibration mechanisms. Research on optimal sensor placement has become a very important topic due to the need to obtain effective testing information from limited test resources. To overcome inadequacies of the present methods, this paper puts forward the triaxial effective independence driving-point residue （EfI3-DPR3） method for optimal sensor placement. The Efl3-DPR3 method can incorporate both the maximum triaxial modal kinetic energy and linear independence of the triaxial target modes at the selected nodes. It was applied to the optimal placement oftriaxial sensors for vibration testing in a hydropower house, and satisfactory results were obtained. This method can provide some guidance for optimal placement of triaxial sensors of underground powerhouses.

关键词： triaxial sensor " optimal placement " Efl3-DPR3 method " hydropower house "vibration testing

Wave force on composite bucket foundation of an offshore wind turbine

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Journal of Hydrodynamics 2016年第1期28卷 33-42页

作者：练继建于通顺张金凤 State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University College of Engineering Ocean University of China

A new analytical expression for calculating the wave force on a composite bucket foundation is obtained. Based on the diffraction theory, the analytical solution of the wave pressure and the wave force on the composite bucket foundation is accurately derived by assigning reasonable boundary conditions. Experiments for the wave pressure on the bucket foundation with a scale of 1：60 under different wave conditions in the wave flume are designed and conducted. The analytical results agree well with the experimental data, and the theoretical approach can accurately predict the wave force on the large-scale structures. The wave pressure distribution on the composite bucket foundation is presented and the influence of the wave height, the water depth and the wave period on the wave force on the composite bucket foundation is investigated. This study provides a quite accurate method to calculate the wave force on a composite bucket foundation, which gives a good framework for future studies of the wave force on other large-scale structures with complex boundaries.

关键词： wave force composite bucket foundation diffraction theory wave flume

Preparation and Performance of Ternary Early Strength Agent and Quercetin Composite Cement Sealing Material

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 130-140页

作者： LIU jian CHEN Meiting ji Xiaoli XU Chao WANG Chunmei Department of Safety Science and Engineering Anhui University of Science and TechnologyHuainan 232001China Key Laboratory of Mine Safety and High Efficient Mining Jointly Built by Province and Education Ministry Anhui University of Science and TechnologyHuainan 232001China Department of Chemical Engineering and Explosives Anhui University of Science and TechnologyHuainan 232001China

A ternary early-strengthening agent consisting of calcium formate+triethanolamine+lithium sulfate was compounded with quercetin to shorten the setting time of cementitious materials while ensuring their early *** optimum ratio of the three early-strengthening agents was determined as 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate by response surface *** effects of the ternary early-strengthening agent composed of calcium formate+triethanolamine(TEA)+lithium sulfate on cementitious pore sealing materials under the synergistic effect of quercetin were studied by means of the performance tests of compressive strength,fluidity,and setting time,and the microstructural characterizations of X-ray powder diffractometer(XRD),thermogravimetry(TG-DSC)and scanning electron microscopy(SEM).The study shows that the synergistic effect of ternary early-strengthening agent and quercetin forms a multi-performance composite admixture for cementitious *** best performance was obtained with the compounding scheme of 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate ternary early-strengthening agent and 0.05%*** compressive strength of 1,3,7,and 28 d are 94.8%,39.8%,42%,and 28%higher than those of the blank group,*** initial time and final setting time are 41 and 57 minutes,*** to the microscopic analysis,the network and fibrous C-S-H gels generated by ternary early-strengthening agents are attached to the surface promoted by quercetin,which forms skeleton support while thickening and solidifying the cement slurry,which enhances the early compressive strength of the cement-based materials.

关键词： sealing material ternary early-strengthening agent quercetin synergetic effect response surface methodology

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随机载荷下风电齿轮箱太阳轮疲劳寿命预测

兰州理工大学学报 2017年第5期43卷 47-50页

作者：敬志臣王建吉连潇陇东学院机械工程学院甘肃庆阳745000 兰州理工大学机电工程学院甘肃兰州730050

以2 MW水平轴变速风力发电机齿轮箱中的太阳轮为研究对象,选用双参数Weibull分布描述风场风速的统计规律,以此作为齿轮箱的外部载荷激励,并通过Monte Carlo方法进行仿真模拟得到太阳轮的应力分布.基于随机载荷作用下零件疲劳寿命的预测... 详细信息

以2 MW水平轴变速风力发电机齿轮箱中的太阳轮为研究对象,选用双参数Weibull分布描述风场风速的统计规律,以此作为齿轮箱的外部载荷激励,并通过Monte Carlo方法进行仿真模拟得到太阳轮的应力分布.基于随机载荷作用下零件疲劳寿命的预测模型对风电齿轮箱中太阳轮的疲劳寿命进行预测,结果表明:该方法能够有效预测随机载荷作用下太阳轮的疲劳寿命,对风电齿轮箱零件的疲劳寿命预测与评估具有一定的指导意义.

关键词：风电齿轮箱随机载荷 Monte Carlo方法疲劳寿命

Influence of Incomplete Soil Plugs on Bearing Capacities of Bucket Foundations in Clay

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China Ocean Engineering 2024年第1期38卷 144-155页

作者： LI Hui-shan LIU Run YANG Xu lian ji-jian State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China Institute of Marine Energy and Intelligent Construction Tianjin University of TechnologyTianjin 300384China

Due to the uneven seabed and heaving of soil during pumping,incomplete soil plugs may occur during the installation of bucket foundations,and the impacts on the bearing capacities of bucket foundations need to be *** this paper,the contact ratio(the ratio of the top diameter of the soil plug to the diameter of the bucket)and the soil plug ratio(the ratio of the soil heave height to the skirt height)are defined to describe the shape and size of the incomplete soil ***,finite element models are established to investigate the bearing capacities of bucket foundations with incomplete soil plugs and the influences of the contact ratios,and the soil plug ratios on the bearing capacities are *** results show that the vertical bearing capacity of bucket foundations in homogeneous soil continuously improves with the increase of the contact ***,in normally consolidated soil,the vertical bearing capacity barely changes when the contact ratio is smaller than 0.75,while the bearing capacity suddenly increases when the contact ratio increases to 1 due to the change of failure *** contact ratio hardly affects the horizontal bearing capacity of bucket ***,the moment bearing capacity improves with the increase of the contact ratio for small aspect ratios,but hardly varies with increasing contact ratio for aspect ratios larger than ***,the reduction coefficient method is proposed based on this analysis to calculate the bearing capacities of bucket foundations considering the influence of incomplete soil *** comparison results show that the proposed reduction coefficient method can be used to evaluate the influences of incomplete soil plug on the bearing capacities of bucket foundations.

关键词： bucket foundation incomplete soil plug uniaxial bearing capacity contact ratio soil plug ratio

考虑场地效应的多点地震动作用下边坡永久位移分析

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岩土工程学报 2025年第1期47卷 65-75页

作者：宋健潘驭航陆朱汐姬建张飞高玉峰河海大学岩土力学与堤坝工程教育部重点实验室江苏南京210024 河海大学土木与交通学院江苏南京210024

地震动引起的边坡土层非线性动力响应可能导致坡体不同位置的地震动加速度时程不一致,从而对整个滑动体的极限平衡状态及之后的地震累积永久位移产生影响。为了研究场地效应对边坡地震永久位移的影响,基于极限平衡条分法,通过对不同土... 详细信息

地震动引起的边坡土层非线性动力响应可能导致坡体不同位置的地震动加速度时程不一致,从而对整个滑动体的极限平衡状态及之后的地震累积永久位移产生影响。为了研究场地效应对边坡地震永久位移的影响,基于极限平衡条分法,通过对不同土条赋予不同的水平和竖向地震动时程,推导出一种考虑场地效应的圆弧和任意形状滑面的多点地震作用下边坡永久位移分析方法。通过与有限差分软件FLAC的数值模拟结果进行对比,验证了该方法能够合理考虑地震动的场地效应。通过研究不同分布形式的多点地震动及竖向地震动对边坡永久位移的影响,结果表明:场地效应引起的水平地震动放大以及多点地震动不同分布模式会导致整个滑体平均地震惯性力作用位置发生改变,从而影响地震作用下滑动体沿滑面的永久变形量,竖向地震动对边坡地震位移影响较小。将方法应用于Lexington土石坝震后变形案例分析,计算得到的坝坡地震永久位移与实际震后观测值相吻合,证明了考虑场地效应的重要性及本文方法的合理性。

关键词：地震边坡稳定性场地效应永久位移极限平衡条分法多点地震动

Upper Bound Solution of the Resisting Moment Bearing Capacity of A Composite Bucket Shallow Foundation of An Offshore Wind Turbine in Sand

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China Ocean Engineering 2022年第6期36卷 859-870页

作者： LIU Run LI Tian-liang CHEN Guang-si lian ji-jian State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China

Bearing the large moment that is generated by the wind load that acts on the upper structure of offshore wind turbines is an important feature of their foundations that is different from other offshore structures.A composite bucket shallow foundation(CBSF)has been proposed by Tianjin University to address the soft geological conditions in the offshore regions of China for wind *** CBSF is a new type of foundation and is effective against large *** soil deformation test of a CBSF and the numerical simulation study under the same working conditions are carried out to determine the failure mechanism of a CBSF under moment *** resisting soil compression rateηm is defined as a new empirical parameter that indicates the ability of the soil inside the bucket to resist moment *** upper limit of the resisting moment bearing capacity of the bucket foundation is derived through the upper bound theorem of classical plasticity theory based on the failure *** calculation method is validated by tests of bucket models with different height-diameter ratios in sand under moment loading.

关键词： bucket foundation failure mechanism resisting moment bearing capacity upper bound theorem resisting soil compression rate

Pharmacological targeting cGAS/STING/NF-κB axis by tryptanthrin induces microglia polarization toward M2 phenotype and promotes functional recovery in a mouse model of spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3287-3301页

作者： Ziwei Fan Mengxian jia jian Zhou Zhoule Zhu Yumin Wu Xiaowu Lin Yiming Qian jiashu lian Xin Hua jianhong Dong Zheyu Fang Yuqing Liu Sibing Chen Xiumin Xue Juanqing Yue Minyu Zhu Ying Wang Zhihui Huang Honglin Teng Department of Orthopedics(Spine Surgery) the First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina School of Pharmacy Hangzhou Normal UniversityHangzhouZhejiang ProvinceChina Department of Neurology The First Affiliated Hospital of Wenzhou Medical UniversityWenzhouZhejiang ProvinceChina Department of Pathology Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhouZhejiang ProvinceChina Department of Clinical Research Center Affiliated Hangzhou First People’s HospitalSchool of MedicineWestlake UniversityHangzhouZhejiang ProvinceChina

The M1/M2 phenotypic shift of microglia after spinal cord injury plays an important role in the regulation of neuroinflammation during the secondary injury phase of spinal cord *** of shifting microglia polarization from M1(neurotoxic and proinflammatory type)to M2(neuroprotective and anti-inflammatory type)after spinal cord injury appears to be *** possesses an anti-inflammatory biological ***,its roles and the underlying molecular mechanisms in spinal cord injury remain *** this study,we found that tryptanthrin inhibited microglia-derived inflammation by promoting polarization to the M2 phenotype in *** promoted M2 polarization through inactivating the cGAS/STING/NF-κB ***,we found that targeting the cGAS/STING/NF-κB pathway with tryptanthrin shifted microglia from the M1 to M2 phenotype after spinal cord injury,inhibited neuronal loss,and promoted tissue repair and functional recovery in a mouse model of spinal cord ***,using a conditional co-culture system,we found that microglia treated with tryptanthrin suppressed endoplasmic reticulum stress-related neuronal *** together,these results suggest that by targeting the cGAS/STING/NF-κB axis,tryptanthrin attenuates microglia-derived neuroinflammation and promotes functional recovery after spinal cord injury through shifting microglia polarization to the M2 phenotype.

关键词： cGAS/STING functional recovery microglia neuroinflammation neuroprotection nuclear factor-κB polarization spinal cord injury tryptanthrin