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High-performance computing of 3D blasting wave propagation in underground rock cavern by using 4D-LSM on TianHe-3 prototype E class supercomputer

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Deep Underground Science and Engineering 2022年第1期1卷 87-100页

作者： Meng Fu gaofeng zhao State Key Laboratory of Hydraulic Engineering Simulation and Safety School of Civil EngineeringTianjin UniversityTianjinChina

Parallel computing assigns the computing model to different processors on different devices and implements it ***,it has broad applications in the numerical simulation of geotechnical engineering and underground engineering,of which models are always *** parallel computing,the computing time or the memory requirements will be reduced by splitting the original domain of the numerical model into many subdomains,which is thus named as the domain decomposition *** this study,a cubic and equal volume domain decomposition strategy was utilized to realize the parallel computing on the distributed memory system of four-dimensional lattice spring model(4D-LSM)based on the message passing *** a more efficient communication strategy introduced,this study aimed at operating an one-billion-particle model on a supercomputer *** preprocessing procedure of the parallelized 4D-LSM was restructured and the particle generation strategy suitable for the supercomputer platform was employed to minimize the time consumption in preprocessing and *** this basis,numerical calculations were performed on TianHe-3 prototype E class supercomputer at the National Supercomputer Center in *** fieldscale three-dimensional blasting wave propagation models were carried out,of which the numerical results verify the computing power and the advantage of the parallelized 4D-LSM in the simulation of large-scale three-dimension ***,the time complexity and spatial complexity of 4D-LSM and other particle discrete element methods were analyzed.

关键词： domain decomposition method lattice spring model parallel computing wave propagation

Modeling stress wave propagation in rocks by distinct lattice spring model

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第4期6卷 348-355页

作者： gaofeng zhao Centre for Infrastructure Engineering and Safety School of Civil and Environmental Engineering The University of New South Wales

In this paper, the ability of the distinct lattice spring model （DLSM） for modeling stress wave propagation in rocks was fully investigated. The influence of particle size on simulation of different types of stress waves （e.g. one-dimensional （1D） P-wave, 1D S-wave and two-dimensional （2D） cylindrical wave） was studied through comparing results predicted by the DLSM with different mesh ratios （It） and those obtained from the corresponding analytical solutions. Suggested values of lr were obtained for modeling these stress waves accurately. Moreover, the weak material layer method and virtual joint plane method were used to model P-wave and S-wave propagating through a single discontinuity. The results were compared with the classical analytical solutions, indicating that the virtual joint plane method can give better results and is recommended. Finally, some remarks of the DLSM on modeling of stress wave propagation in rocks were provided.

关键词： Distinct lattice spring model Rock Stress wave Verification

Numerical study of the semi-circular bend dynamic fracture toughness test using discrete element models

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Science China(Technological Sciences) 2015年第9期58卷 1587-1595页

作者： zhao gaofeng KAZERANI Tohid MAN Ke GAO Mz zhao Jian State Key Laboratory of Hydraulic Engineering Simulation and Safety School of Civil Engineering Tianjin University Centre for Infrastructure Engineering and Safety School of Civil and Environmental Engineering University of New South Wales State Key Lab of Hydraulics and Mountain River Engineering Sichuan University Civil Engineering School Faculty of Engineering University of Nottingham University Park Beijing Research Institute of Uranium Geology Department of Civil Engineering Monash University

The semi-circular bend(SCB) dynamic fracture toughness test is simulated using discrete element models. The influence of the frictional boundary condition, constitutive law and specimen thickness on the test measurements is investigated. It is found that friction between loading plates and the rock specimen affects the test results. Therefore, friction must be carefully considered to obtain accurate measurements. The simulation results also show that in contrast to the 2D model in which a rate-dependent cohesive law must be introduced, 3D models with a rate-independent law can produce good results. Furthermore, the study suggests that test measurements are seriously affected by specimen thickness; thus, full 3D modeling is required for simulation of the SCB test.

关键词： dynamic fracture toughness rock discrete element model friction

Effect of electrically stimulating acupoint, Zusanli(ST 36), on patient’s recovery after laparoscopic colorectal cancer resection: a randomized controlled trial

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Journal of Traditional Chinese Medicine 2019年第3期39卷 433-439页

作者： Huang Wei Yu Tingyu Long Wenfei Xiao Jianbin zhao gaofeng Department of Anesthesiology Guangdong Provincial Hospital of Chinese Medicine Guangzhou 510000 China Second Clinical Medical College Guangzhou University of Chinese Medicine Guangzhou 510000 China

OBJECTIVE:To investigate the effect of transcutaneous electrical acupoint stimulation (TEAS) on enhanced recovery after surgery (ERAS) in laparoscopic colorectal cancer resection and its clinical ***:Sixty-four patients undergoing laparoscopic colorectal resection were randomly divided into two groups,the control group (group A) and the TEAS group (group B).Patients in the TEAS group received electroacupuncture stimulation of bilateral Zusanli (ST 36) at 30 min before anesthesia to the end of *** patients in the control group were not given the *** anesthesia management of the two groups were performed according to the ERAS guidelines,and postoperative patient-controlled intravenous analgesia (PCIA) was *** amount of remifentanil used in the two groups was observed and recorded,and the visual analogue scale (VAS) of the 4,12,24 and 48 h after surgery in the two groups was ***,postoperative anal exhaust time,postoperative feeding time,postoperative first ambulation time and postoperative hospital stay length were compared between the two ***:Compared with group A,the VAS score of group B decreased significantly at 48 h after operation (P 0.05).CONCLUSION:TEAS can promote the recovery of postoperative gastrointestinal function and reduce the pain intensity 48 h after surgery,thus satisfying the need of early postoperative analgesia.

关键词： Colorectal neoplasms Laparoscopes Transcutaneous electric nerve stimulation Recovery of function Randomized controlled trial

1D/2D composite subnanometer channels for ion transport:The role of confined water

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Nano Research 2023年第8期16卷 10913-10921页

作者： Yuhao Li Xiaorui Jin Xinhai Yan Xinyu Ai Xin Yang Zi-Jian Zheng Kun Huang gaofeng zhao Yongan Yang Meiling Wu Kai-Ge Zhou Institute of Molecular Plus Department of ChemistryTianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials Hubei Key Laboratory of Polymer MaterialsHubei UniversityWuhan 430062China School of Chemical Engineering and Analytical Science National Graphene InstituteUniversity of ManchesterManchesterM139PLUK School of Civil Engineering Tianjin UniversityTianjin 300072China

As a mass transport media,water is an alternative of organic solvent applied in rechargeable batteries,due to its unique properties,including fast ionic migration,easy-processibility,economic/environmental friendliness,and flame ***,due to the high activity of water molecules in aqueous electrolytes,the corrosion of metal anode,side reactions,and inferior metal electrodeposition behavior leads to unstable cycling performance,poor Coulombic efficiency(CE),and early-staged failure of *** several attempts to regulate the activity of water,migration of ions is sacrificed,due to the limited methods to control the water ***,we developed a subnanoscale confinement strategy based on a nacre-like structure to modulate the activity of water in the solid *** tuning the ratio between the two-dimensional(2D)vermiculite and one-dimensional(1D)cellulose nanofibers(CNFs),the capillary size in the 1D/2D structure is altered to achieve a fast Zn^(2+)*** dielectric relaxation and molecular dynamics studies indicate that the enhanced Zn^(2+)conductivity is attributed to the fast water relaxation in the precisely defined 1D/2D *** advantage of the regulated activity of the confined water in 2D capillary,the composite vermiculite membrane can suppress the corrosion and side reactions between Zn electrode and water molecular,endowing a reversible Zn^(2+)stripping/plating behavior and a stable cycling performance for 900 *** on our confinement strategy to control the water states by 1D/2D structures,this work will open an avenue toward aqueous energy storage devices with excellent reversibility,high safety,and long-term stability.

关键词： ion transport subnanometer channels confined water aqueous electrolyte limited side reactions

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基于阿里云的四维弹簧模型并行运算性能

土木与环境工程学报（中英文） 2019年第3期41卷 1-10页

作者：赵高峰陈华天津大学建筑工程学院水利工程仿真与安全国家重点实验室天津300072

四维弹簧模型(Four-Dimensional Lattice Spring Model,4D-LSM)是一种考虑额外维相互作用的新型离散数值计算方法。该方法用于岩石破坏分析需要消耗大量计算资源,不适合在普通个人电脑上运行。基于多核并行技术,在阿里云和多核工作站等... 详细信息

四维弹簧模型(Four-Dimensional Lattice Spring Model,4D-LSM)是一种考虑额外维相互作用的新型离散数值计算方法。该方法用于岩石破坏分析需要消耗大量计算资源,不适合在普通个人电脑上运行。基于多核并行技术,在阿里云和多核工作站等多种硬件环境下对4D-LSM的计算极限性能及瓶颈进行详细分析,主要研究了求解规模、求解类型、线程数、硬件配置等对4D-LSM求解效能的影响。研究发现,内存容量决定可计算的模型规模,弹性问题的计算时间与模型规模成正比,并行计算效率受CPU性能和内存带宽的共同影响。在不考虑经济因素的情况下,云计算在多核匹配和内存分配方面的灵活性特别适合于四维弹簧模型的并行计算分析。结果表明:基于阿里云的4D-LSM最大运算规模可以达到十亿单元,由于目前的瓶颈在于前后处理,4D-LSM目前的可分析规模仍然限制在两千万单元。最后,展示了采用极限规模的并行四维弹簧模型求解三维币形裂纹扩展的实际应用案例。

关键词：云计算四维弹簧模型并行计算三维裂纹扩展

基于四维离散数值方法的岩石圆环试样动态破坏及耗能规律

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土木与环境工程学报（中英文） 2019年第2期41卷 20-28页

作者：张奔赵高峰天津大学建筑工程学院天津300072

利用最新提出的四维离散弹簧元法(4D-LSM)对岩石圆环的动态抗变形及耗能特性进行研究。首先对4D-LSM用于描述岩石圆环试样破坏的适用性进行了验证,发现4D-LSM可以较好地再现岩石试样的孔径比与破坏形态和强度间的影响规律。在此基础上,... 详细信息

利用最新提出的四维离散弹簧元法(4D-LSM)对岩石圆环的动态抗变形及耗能特性进行研究。首先对4D-LSM用于描述岩石圆环试样破坏的适用性进行了验证,发现4D-LSM可以较好地再现岩石试样的孔径比与破坏形态和强度间的影响规律。在此基础上,对孔隙率、非均质性、厚径比等因素与抗变形及耗能间的规律进行研究,得到了对应的数学公式。利用4D-LSM模拟大变形方面的优势,发现当岩石材料的变形抵抗能力较大时,岩石圆环将表现出与传统仅考虑小变形情况下实验和数值计算不同的破坏形态,岩石圆环的材料抗拉强度与抗变形能力也分别呈现非线性关系。通过建立圆环阵列模型,研究了由多个岩环构成的组合结构的抗变形和能量抵抗能力以及对应的破坏形态。结果表明,组合结构中的圆环单元与单圆环受力的破裂形态有所不同,但单圆环的抗变形及耗能规律仍适用于岩环阵列结构的分析。

关键词：四维离散弹簧元法岩石圆环耗能变形

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基于声发射监测的岩石热损伤实时演化研究

中南大学学报（自然科学版） 2021年第8期52卷 2945-2958页

作者：张玉良吴必胜赵高峰天津大学水利工程仿真与安全国家重点实验室天津300354 清华大学水利水电工程系北京100084

为了建立岩石热损伤演化模型,基于NI高性能测试系统与LabVIEW开发环境,通过对不同岩性试样(3种花岗岩和3种砂岩)进行热损伤试验,捕捉岩石在升温(从室温到500℃)和降温过程中的声发射信息。采用薄片分析方法揭示岩石经历高温作用前后的... 详细信息

为了建立岩石热损伤演化模型,基于NI高性能测试系统与LabVIEW开发环境,通过对不同岩性试样(3种花岗岩和3种砂岩)进行热损伤试验,捕捉岩石在升温(从室温到500℃)和降温过程中的声发射信息。采用薄片分析方法揭示岩石经历高温作用前后的微观结构。根据声发射能量与弹性模量,建立岩石热损伤演化模型。研究结果表明:岩石在经历高温作用后微观裂隙增多,薄片糙面粗糙度增大;声发射信号频率存在2个明显的区间,即0.1~20 kHz和20~80 kHz,声发射幅值主要集中在50~70 dB;不同岩石的声发射能量存在显著差异,花岗岩的热损伤主要集中在升温段,砂岩的热损伤主要集中在降温段,揭示了岩石热损伤演化具有高度的岩性依赖性。岩石热损伤演化模型较好地表征了岩石损伤变量随温度升高和降低的演化;花岗岩和砂岩热损伤过程中的损伤机理存在明显的差异,花岗岩中结晶颗粒的面-面接触使其具有非均匀变形和含缺陷矿物颗粒导致的双重损伤机理,砂岩碎屑颗粒的点-点接触关系导致其损伤中以含缺陷矿物导致的降温损伤机理为主。

关键词：声发射岩石热损伤深地热损伤机理

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紫精类变色材料的合成与应用研究

过程工程学报 2022年第3期22卷 304-317页

作者：赵高峰赵炜珍刘晓敏青岛大学化学化工学院山东青岛266071 中国科学院过程工程研究所北京100190

紫精是一种具有显著光学对比度、较高着色效率、独特氧化还原稳定性的化合物。它易于进行分子设计以及被用于大面积器件的制作。由于其独特的性能,紫精类变色材料在军事伪装、屏幕显示、信息存储、智能变色窗等领域都有着广泛的应用前景... 详细信息

紫精是一种具有显著光学对比度、较高着色效率、独特氧化还原稳定性的化合物。它易于进行分子设计以及被用于大面积器件的制作。由于其独特的性能,紫精类变色材料在军事伪装、屏幕显示、信息存储、智能变色窗等领域都有着广泛的应用前景,成为当前研究的热点之一。随着智能材料的迅速发展,科研工作者对紫精基变色材料(包括小分子紫精衍生物、紫精功能共轭聚合物,基于紫精的有机/无机复合材料)的研究也逐渐深入。本工作对近年来紫精变色材料的研究进展进行了综述,重点介绍了紫精的合成与应用、离子液体和聚离子液体在紫精变色领域中的应用以及目前国内外企业和研究单位的研究现状,并从工业应用方向讨论了紫精变色材料目前存在的问题和未来的潜在应用。

关键词：紫精变色机理合成应用