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A three-dimensional CFD numerical simulation study on pressurized oxy-fuel gasification of poultry manure in an industrial-scale gasifier
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作者 Qinwen Liu Guoqing Lian +4 位作者 Wenli Dong Yu Su Wei Quan Leong Chi-Hwa Wang Wenqi Zhong 《Chinese Journal of Chemical Engineering》 2025年第5期115-127,共13页
As a renewable energy source,the thermal conversion of poultry manure,is a promising waste treatment solution that can generate circular economic outputs such as energy and reduce greenhouse gas emissions.Currently,pr... As a renewable energy source,the thermal conversion of poultry manure,is a promising waste treatment solution that can generate circular economic outputs such as energy and reduce greenhouse gas emissions.Currently,pressurized gasification of poultry manure is still a novel research field,especially when combined with a novel technological route of oxy-fuel gasification.Oxy-fuel gasification is a newly proposed and promising gasification technology for power generation that facilitates future carbon capture and storage.In this work,based on a commercially operated industrial-scale chicken manure gasification power plant in Singapore,we presented an interesting first exploration of the coupled pressurization technology for oxy-fuel gasification of poultry manure using CFD numerical simulation,analyzed the effects of pressure and oxygen enrichment concentration as well as the coupling mechanism between them,and discussed the conversion and emission of nitrogen-and sulfur-containing pollutants.The results indicate that under oxy-fuel gasification condition(Oxy-30,i.e.,30%O_(2)/70%CO_(2)),as the pressure increases from 0.1 to 0.5 MPa,the CO concentration in the syngas increases slightly,the H_(2)concentration increases to approximately 25%,and the CH4 concentration(less than 1%)decreases,resulting in an increase in the calorific value of syngas from 5.2 to 5.6 MJ·m^(-3).Compared to atmospheric pressure conditions,a relatively higher oxygen-enriched concentration interval(Oxy-40 to Oxy-50)under pressurized conditions is advantageous for autothermal gasification.Pressurization increases NO precursors production and also promotes homogeneous and heterogeneous reduction of NO,and provides favorable conditions for self-desulfurization.This work offers reference for the realization of a highly efficient and low-energy-consumption thermochemical treatment of livestock manure coupled with negative carbon emission technology. 展开更多
关键词 Oxy-fuel gasification Pressurized gasification Poultry manure Carbon negative cfd numerical simulation
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A three-dimensional CFD study of the hydrodynamic behavior of equal and unequal-sized in-line methane bubbles at high pressure
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作者 Nikolaos A.Avgerinos Dionissios P.Margaris 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第9期1792-1802,共11页
The hydrodynamic behavior of multiple bubbles rising upward is a field of ongoing research since various aspects of their interaction require further analysis. Shape deformation, rise velocity, and drag coefficient ar... The hydrodynamic behavior of multiple bubbles rising upward is a field of ongoing research since various aspects of their interaction require further analysis. Shape deformation, rise velocity, and drag coefficient are some of the uncertainties to be determined in a bubble upward flow. For this study the predictions of the three-dimensional numerical simulations of the volume of fluid(VOF) CFD model were first compared with experimental results available in the literature, serving as benchmark cases. Next, 28 cases of pairs of equal and unequal-sized in-line pairs of bubbles moving upwards were simulated. The bubble size varied between 2.0–10 mm. Breakthrough of the present study is the small initial distance of 2.5 R between the center of the bubbles. To provide a more practical nature in this study material properties were selected to match methane gas and seawater properties at deepsea conditions of 15 MPa and 4 ℃, thus yielding a fluid-to-bubble density ratio λ = 7.45 and viscosity ratio n = 100.46. This is one of the few studies to report results of the coalescence procedure in this context. The hydrodynamic behavior of the leading and trailing bubbles was thoroughly studied. Simulation results of the evolution of the rise velocity and the shape deformation with time indicate that the assumption that the leading bubble is rising as a free rising single one is not valid for bubbles between 2.0–7.0 mm. Finally, results of the volume of the daughter bubble exhibited an oscillating nature. 展开更多
关键词 BUBBLE COALESCENCE Computational fluid dynamics cfd METHANE Rise velocity Shape deformation
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Accurate closed-form flutter eigensolutions of three-dimensional composite laminates with shear deformation
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作者 Dezhuang PAN Yufeng XING 《Chinese Journal of Aeronautics》 2026年第1期230-246,共17页
According to the Mindlin plate theory and the first-order piston theory,this work obtains accurate closed-form eigensolutions for the flutter problem of three-dimensional(3D)rectangular laminated panels.The governing ... According to the Mindlin plate theory and the first-order piston theory,this work obtains accurate closed-form eigensolutions for the flutter problem of three-dimensional(3D)rectangular laminated panels.The governing differential equations are derived by the Hamilton's variational principle,and then solved by the iterative Separation-of-Variable(i SOV)method,which are applicable to arbitrary combinations of homogeneous Boundary Conditions(BCs).However,only the simply-support,clamped and cantilever panels are considered in this work for the sake of clarity.With the closed-form eigensolutions,the flutter frequency,flutter mode and flutter boundary are presented,and the effect of shear deformation and aerodynamic damping on flutter frequencies is investigated.Besides,the relation between panel energy and the work of aerodynamic load is discussed.The numerical comparisons reveal the following.(A)The flutter eigenvalues obtained by the present method are accurate,validated by the Finite Element Method(FEM)and the Galerkin method.(B)When the span-chord ratio is larger than 3,simplifying a 3D panel to 2D(two-dimensional)panel is reasonable and the relative differences of the flutter points predicted by the two models are less than one percent.(C)The reciprocal relationship between the mechanical energy of the panel and the work done by aerodynamic load is verified by using the present flutter eigenvalues and modes,further indicating the high accuracy of the present solutions.(D)The coupling of shear deformation and aerodynamic damping prevents frequency coalescing. 展开更多
关键词 Closed-form eigensolutions The first-order piston theory The Mindlin plate theory three-dimensional panel flutter Separation-of-variable method
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Numerical aerodynamic analysis of bluff bodies at a high Reynolds number with three-dimensional CFD modeling 被引量:4
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作者 BAI YuGuang YANG Kai +4 位作者 SUN DongKe ZHANG YuGuang KENNEDY David WILLIAMS Fred GAO XiaoWei 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第2期277-289,共13页
This paper focuses on numerical simulations of bluff body aerodynamics with three-dimensional CFD(computational fluid dynamics) modeling,where a computational scheme for fluid-structure interactions is implemented.The... This paper focuses on numerical simulations of bluff body aerodynamics with three-dimensional CFD(computational fluid dynamics) modeling,where a computational scheme for fluid-structure interactions is implemented.The choice of an appropriate turbulence model for the computational modeling of bluff body aerodynamics using both two-dimensional and three-dimensional CFD numerical simulations is also considered.An efficient mesh control method which employs the mesh deformation technique is proposed to achieve better simulation results.Several long-span deck sections are chosen as examples which were stationary and pitching at a high Reynolds number.With the proposed CFD method and turbulence models,the force coefficients and flutter derivatives thus obtained are compared with the experimental measurement results and computed values completely from commercial software.Finally,a discussion on the effects of oscillation amplitude on the flutter instability of a bluff body is carried out with extended numerical simulations.These numerical analysis results demonstrate that the proposed three-dimensional CFD method,with proper turbulence modeling,has good accuracy and significant benefits for aerodynamic analysis and computational FSI studies of bluff bodies. 展开更多
关键词 bluff body aerodynamic analysis fluid-structure interaction three-dimensional cfd modeling FLUTTER
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基于CFD-DEM的微阀射流疏堵模拟研究
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作者 魏列江 张海东 +3 位作者 魏小玲 刘豆豆 陈阳 强彦 《机床与液压》 北大核心 2026年第3期164-170,共7页
针对微阀在长期使用中因微小颗粒物沉积与黏附导致流道堵塞的问题,提出一种通过手指按压储液囊形成射流进行疏通的方法,清除堵塞物的同时避免损伤微阀结构。针对阀芯-阀座间颗粒团聚形成的堵塞,采用CFD-DEM耦合仿真方法,通过改变按压储... 针对微阀在长期使用中因微小颗粒物沉积与黏附导致流道堵塞的问题,提出一种通过手指按压储液囊形成射流进行疏通的方法,清除堵塞物的同时避免损伤微阀结构。针对阀芯-阀座间颗粒团聚形成的堵塞,采用CFD-DEM耦合仿真方法,通过改变按压储液囊时间,研究不同射流条件下颗粒聚集状态。仿真结果表明:当匀速按压时间为1.5 s时,射流速度增长平缓,只有20%的颗粒被冲刷出堵塞位置;按压时间为0.5 s时,射流速度迅速增大,97%的颗粒被冲刷掉,有效改善了微阀堵塞,按压时间显著影响疏堵效率。为进一步验证所提方法的有效性,使用放大样机进行实验验证。结果表明:按压1.5 s后,堵塞的明胶颗粒未能被完全冲刷,大量颗粒仍滞留于阀座区域;而按压时间缩短至0.5 s后,阀芯与阀座之间的明胶颗粒几乎完全被清除,微阀恢复正常工作状态。实验与仿真结果一致,证明基于CFD-DEM耦合仿真模拟按压储液囊射流冲刷堵塞物的方法可行。 展开更多
关键词 微阀 颗粒 堵塞 射流 cfd-DEM
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半解析CFD-DEM耦合方法研究进展
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作者 许成顺 苏卓林 +1 位作者 徐佳琳 吴昕怡 《土木工程学报》 北大核心 2026年第2期1-19,共19页
流体-颗粒相互作用广泛存在于岩土工程、生物能源与工业过程等领域,CFD-DEM耦合方法因其能同时解析流体连续相与颗粒离散相的动态行为,已成为该类多相系统模拟的主流手段。文章系统综述了CFD-DEM耦合方法,重点聚焦于近年来快速发展的半... 流体-颗粒相互作用广泛存在于岩土工程、生物能源与工业过程等领域,CFD-DEM耦合方法因其能同时解析流体连续相与颗粒离散相的动态行为,已成为该类多相系统模拟的主流手段。文章系统综述了CFD-DEM耦合方法,重点聚焦于近年来快速发展的半解析策略。首先梳理了离散单元法在接触模型与非球形颗粒建模方面的进展;其次对比了全解析、非解析与半解析三类耦合方法的适用条件与技术特点;进而详细评述了基于统计核函数、扩散平滑、双网格及粒子点云等主流半解析算法的原理、优势与局限。最后,针对复杂颗粒形态处理、致密饱和体系模拟、多物理场耦合及机器学习融合等方面的挑战,提出未来研究方向。该文旨在为相关领域研究者提供方法选择与模型开发的参考依据,促进半解析CFD-DEM方法在岩土工程及相关领域的深入应用与发展。 展开更多
关键词 cfd-DEM耦合 半解析方法 流体颗粒相互作用 孔隙场重构
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横摇激励对压裂船混砂罐中固-液两相混合特性影响的CFD模拟
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作者 郑雨杭 何霞 +3 位作者 王国荣 陈林燕 张万春 刘清友 《西南石油大学学报(自然科学版)》 北大核心 2026年第1期95-106,共12页
混砂罐是压裂作业的核心装备,其搅拌效果决定了压裂液的性能,并进一步影响压裂作业进程。针对海洋晃动载荷对压裂船混砂罐内部混合过程的作用不明确的问题,基于CFD方法建立了考虑横摇激励下的压裂船混砂罐固-液两相混合模型,探究了不同... 混砂罐是压裂作业的核心装备,其搅拌效果决定了压裂液的性能,并进一步影响压裂作业进程。针对海洋晃动载荷对压裂船混砂罐内部混合过程的作用不明确的问题,基于CFD方法建立了考虑横摇激励下的压裂船混砂罐固-液两相混合模型,探究了不同横摇幅值和周期对其混合特性的影响。研究表明:横摇激励主要影响颗粒相的速度与分布,对罐内混合相的整体流场影响不大,且颗粒相表现出与横摇方向相同的运动趋势;颗粒相的分布受到罐体位置的影响,在左倾状态时左侧颗粒相体积分数明显大于不晃动时,右侧则明显小于不晃动时,右倾时则与之相反;横摇激励可以加速混合过程,随着横摇幅值增大或周期降低,罐体左右两侧颗粒相体积分数差异增大,颗粒相下沉趋势更加明显,导致排出口混合相平均密度也随之增加,但排出口密度均匀指数呈现下降的趋势,在T=8 s,A>6°或A=6°,T<8 s时均匀指数低于不晃动时。研究结果可为探究混合类罐体受晃动载荷的影响奠定理论基础。 展开更多
关键词 压裂船 混砂罐 cfd方法 横摇激励 混合特性
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CFD模拟检测核电厂主控室密封性
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作者 王稹 刘思光 +4 位作者 高旭 张渊 吴涛 李晓晨 张雪平 《核电子学与探测技术》 北大核心 2026年第1期57-61,共5页
针对第四代核电高温气冷堆设计的模拟主控室,本研究采用计算流体动力学(Computational Fluid Dynamics,CFD)仿真软件,对主控室房间及通风管道的气流与压力分布进行了模拟计算,并将仿真结果与进风量实测值进行了对比。结果表明:模拟计算... 针对第四代核电高温气冷堆设计的模拟主控室,本研究采用计算流体动力学(Computational Fluid Dynamics,CFD)仿真软件,对主控室房间及通风管道的气流与压力分布进行了模拟计算,并将仿真结果与进风量实测值进行了对比。结果表明:模拟计算流量与实测流量偏差在5%以内,验证了仿真的准确性,表明主控室整体保压情况良好,能够维持12 Pa~14.3 Pa正压,且整体压力随房间高度增加而增大;CFD仿真技术的应用可降低设计与试验成本,为百万千瓦级高温气冷堆主控室通风系统的设计提供技术支持。 展开更多
关键词 cfd仿真 主控室 高温气冷堆 气流分布 正压分布
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基于CFD技术的餐厨垃圾预处理车间臭气收集系统优化研究
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作者 邓兵 陈敏行 雷谱成 《环境卫生工程》 2026年第1期100-108,117,共10页
针对餐厨垃圾预处理车间恶臭气体(以硫化氢为主)收集效率低、能源浪费等问题,本研究结合某县餐厨废弃物无害化处理厂实际案例,采用计算流体力学(CFD)技术对车间气流组织进行数值模拟。通过建立1∶1物理模型(车间尺寸66.65 m×34.50 ... 针对餐厨垃圾预处理车间恶臭气体(以硫化氢为主)收集效率低、能源浪费等问题,本研究结合某县餐厨废弃物无害化处理厂实际案例,采用计算流体力学(CFD)技术对车间气流组织进行数值模拟。通过建立1∶1物理模型(车间尺寸66.65 m×34.50 m×13.40 m),对比分析了卸料门开启数量(0~3个)对应的4种工况下换气次数、风口布局对气流分布的影响。结果表明:排风口集中于中心标高6.00 m处,送风口(标高2.50 m)风量不足且位置不合理,导致一层1.50 m人员呼吸区存在显著死区,工况4(同时开启3个卸料门)时死区面积最大;机械补风量仅设计为排风量的50%,且补风无法穿透设备遮挡区域,造成气流扰动不足。通过调整送/排风口位置、增加低空补风比例,可在满足门洞风速≥0.3 m/s的前提下减少无效换气,降低设备占地与能耗。 展开更多
关键词 计算流体力学 臭气收集 餐厨垃圾 气流组织 数值模拟
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离心纺丝技术:生产设备创新与CFD仿真模拟的进展研究
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作者 郭永康 赵帆 +1 位作者 饶秉钧 王富军 《东华大学学报(自然科学版)》 北大核心 2026年第1期168-179,共12页
离心纺丝技术作为一种兼具低成本与高效率优势的纤维制备方法,在生物医疗和高分子材料等领域具有重要应用价值。本文综述了自1924年Hooper研制首台离心纺丝装置以来,离心纺丝生产设备及技术与计算流体力学(CFD)仿真两方面的研究进展。... 离心纺丝技术作为一种兼具低成本与高效率优势的纤维制备方法,在生物医疗和高分子材料等领域具有重要应用价值。本文综述了自1924年Hooper研制首台离心纺丝装置以来,离心纺丝生产设备及技术与计算流体力学(CFD)仿真两方面的研究进展。在设备层面,纺丝系统从单一纺丝盘逐步发展为多室组合与气流辅助等复杂结构,显著提升了纤维的细度与均匀性;收集系统也实现了从固定式向连续输送式的演进,有效促进了纤维的高效可控沉积。在仿真层面,CFD技术通过气流场模拟与聚合物射流动力学分析,揭示了溶液浓度、转速等关键参数对纺丝过程的影响机制,为工艺优化提供了理论依据。然而,目前该技术仍面临设备定制化程度高、纳米纤维均匀性不足等问题。未来研究应着力于设备集成化以提升对射流动力的微观调控,并发展气流与聚合物直接耦合的多物理场CFD模型,以推动离心纺丝技术向工业化、高性能化方向持续发展。 展开更多
关键词 离心纺丝 cfd仿真 生产设备 纳米纤维
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Direct calculation method of roll damping based on three-dimensional CFD approach 被引量:6
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作者 周耀华 马宁 +1 位作者 石珣 章程 《Journal of Hydrodynamics》 SCIE EI CSCD 2015年第2期176-186,共11页
The effect of roll damping on the prediction of a ship's motion is significant. A method based on the 3-D CFD approach for calculating the roll damping of a ship is proposed in this paper. The free decay experiments ... The effect of roll damping on the prediction of a ship's motion is significant. A method based on the 3-D CFD approach for calculating the roll damping of a ship is proposed in this paper. The free decay experiments of 4 different types of ships at zero velocity are carried out. The roll damping coefficients are calculated and compared with the experiment results, with a good agreement. It is shown that the method adopted in this paper could be used to simulate the free rolling of a ship in the calm water at zero velocity very well and with good, stable accuracy for the prediction of the roll damping, and also with good applicability. This method may be further developed for the prediction of a full scale ship in the future. 展开更多
关键词 roll damping cfd free decay
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基于CFD的浓差极化汲取膜浓缩过程强化研究
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作者 殷嘉伟 杨旭 +3 位作者 沈飞 林春香 万印华 陈国强 《膜科学与技术》 北大核心 2026年第1期154-163,共10页
浓差极化汲取膜浓缩技术能够提取高倍蛋白浓缩液的浓差极化层,具有低剪切、低能耗的优势,但目前仍缺乏浓差极化层的高效汲取方法。为提高该技术对蛋白的浓缩效率,本研究采用计算流体力学(CFD),构建了二维数值模型,系统模拟了外场(重力... 浓差极化汲取膜浓缩技术能够提取高倍蛋白浓缩液的浓差极化层,具有低剪切、低能耗的优势,但目前仍缺乏浓差极化层的高效汲取方法。为提高该技术对蛋白的浓缩效率,本研究采用计算流体力学(CFD),构建了二维数值模型,系统模拟了外场(重力场、电场及重力场电场的复合场)和重要过程参数(蛋白黏度及入口流速)对浓差极化层迁移行为和汲取效率的影响。结果表明,重力场、电场及复合场都能有效促进浓差极化层的迁移。其中,复合场对浓差极化的汲取效率最高。此外,蛋白黏度和入口流速的提高均会对汲取效率产生负面影响。该研究以CFD模拟揭示了施加外场和过程参数对浓差极化汲取技术的重要作用,为该技术的过程强化和控制策略开发提供指导。 展开更多
关键词 浓差极化汲取 cfd模拟 重力场电场的复合场 蛋白黏度 入口流速
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Three-dimensional line-of-sight-angle-constrained leader-following cooperative interception guidance law with prespecified impact time 被引量:3
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作者 Hao YOU Xinlong CHANG Jiufen ZHAO 《Chinese Journal of Aeronautics》 2025年第1期491-506,共16页
To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D lea... To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance law.First,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact time.Next,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the time-to-go.Then,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy consumption.Moreover,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering applications.Finally,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law. 展开更多
关键词 three-dimensional cooperative interception Leader-following missiles Prespecified impact time LOS-angle-constrained Fixed-time stability Global integral sliding mode
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Global Mapping of Three-Dimensional Urban Structures Reveals Escalating Utilization in the Vertical Dimension and Pronounced Building Space Inequality 被引量:1
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作者 Xiaoping Liu Xinxin Wu +6 位作者 Xuecao Li Xiaocong Xu Weilin Liao Limin Jiao Zhenzhong Zeng Guangzhao Chen Xia Li 《Engineering》 2025年第4期86-99,共14页
Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significan... Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significant gap in detailed and consistent data on 3D building space structures with global coverage due to the challenges inherent in the data collection and model calibration processes.In this study,we constructed a global urban structure(GUS-3D)dataset,including building volume,height,and footprint information,at a 500 m spatial resolution using extensive satellite observation products and numerous reference building samples.Our analysis indicated that the total volume of buildings worldwide in2015 exceeded 1×10^(12)m^(3).Over the 1985 to 2015 period,we observed a slight increase in the magnitude of 3D building volume growth(i.e.,it increased from 166.02 km3 during the 1985–2000 period to 175.08km3 during the 2000–2015 period),while the expansion magnitudes of the two-dimensional(2D)building footprint(22.51×10^(3) vs 13.29×10^(3)km^(2))and urban extent(157×10^(3) vs 133.8×10^(3)km^(2))notably decreased.This trend highlights the significant increase in intensive vertical utilization of urban land.Furthermore,we identified significant heterogeneity in building space provision and inequality across cities worldwide.This inequality is particularly pronounced in many populous Asian cities,which has been overlooked in previous studies on economic inequality.The GUS-3D dataset shows great potential to deepen our understanding of the urban environment and creates new horizons for numerous 3D urban studies. 展开更多
关键词 three-dimensional Global mapping Building volume Building height Building space inequality
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Three-dimensional reconstruction under computed tomography and myopectineal orifice measurement under laparoscopy for quality control of inguinal hernia treatment 被引量:1
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作者 Lei Zhang Jing Chen +7 位作者 Yu-Ying Zhang Lei Liu Han-Dan Wang Ya-Fei Zhang Jun Sheng Qiu-Shi Hu Ming-Liang Liu Yi-Lin Yuan 《World Journal of Gastrointestinal Endoscopy》 2025年第3期50-59,共10页
BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are ne... BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are necessary.However,due to differences in race and sex,people’s body shapes vary.According to European guidelines,the patch should measure 10 cm×15 cm.If any part of the MPO is dissected,injury to the nerves,vascular network,or organs may occur during surgery,thereby leading to inguinal discomfort,pain,and seroma formation after surgery.Therefore,accurate localization and measurement of the boundary of the MPO are crucial for selecting the optimal patch for inguinal hernia repair.AIM To compare the size of the MPO measured on three-dimensional multislice spiral computed tomography(CT)with that measured via laparoscopy and explore the relevant factors influencing the size of the MPO.METHODS Clinical data from 74 patients who underwent laparoscopic tension-free inguinal hernia repair at the General Surgery Department of the First Affiliated Hospital of Anhui University of Science and Technology between September 2022 and July 2024 were collected and analyzed retrospectively.Transabdominal preperitoneal was performed.Sixty-four males and 10 females,with an average age of 58.30±12.32 years,were included.The clinical data of the patients were collected.The boundary of the MPO was measured on three-dimensional CT images before surgery and then again during transabdominal preperitoneal.All the preoperative and intraoperative data were analyzed via paired t-tests.A t-test was used for comparisons of age,body mass index,and sex between the groups.In the comparative analysis,a P value less than 0.05 indicated a significant difference.RESULTS The boundaries of the MPO on 3-dimensional CT images measured 7.05±0.47 cm and 6.27±0.61 cm,and the area of the MPO was 19.54±3.33 cm^(2).The boundaries of the MPO during surgery were 7.18±0.51 cm and 6.17±0.40 cm.The errors were not statistically significant.However,the intraoperative BD(the width of the MPO,P=0.024,P<0.05)and preoperative AC(the length of the MPO,P=0.045,P<0.05)significantly differed according to sex.The AC and BD measurements before and during surgery were not significantly different according to age,body mass index,hernia side or hernia type(P>0.05).CONCLUSION The application of this technology can aid in determining the most appropriate dissection range and patch size. 展开更多
关键词 HERNIA INGUINAL Myopectineal orifice three-dimensional reconstruction Computed tomography Inguinal hernia
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空-水双模态跨介质机器人推进性能CFD仿真研究
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作者 孙宇锋 周晶 +1 位作者 赵黎明 刘妹琴 《水下无人系统学报》 2026年第1期94-108,共15页
为应对复杂海洋环境中跨介质作业的需求,针对一款具备空中与水下双模态运动能力的跨介质机器人,开展了推进系统的计算流体力学(CFD)仿真研究。由于空气与水的密度、黏性等物理性质存在显著差异,传统单环境推进器难以兼顾2种介质的高效... 为应对复杂海洋环境中跨介质作业的需求,针对一款具备空中与水下双模态运动能力的跨介质机器人,开展了推进系统的计算流体力学(CFD)仿真研究。由于空气与水的密度、黏性等物理性质存在显著差异,传统单环境推进器难以兼顾2种介质的高效推进。为此,文中建立了涵盖空中与水下2种典型工况的三维瞬态CFD模型,采用滑移网格与流体体积方法,对单螺旋桨与多推进器耦合系统进行对比仿真分析,揭示了跨介质推进系统在推力系数、推进效率与尾流干扰等方面的差异性及规律。结果表明,在3 kn航速下,水下推进系统效率最高可达48.48%,显著高于空中推进系统(7.43%);多推进器协同运行会引起尾流耦合干扰,但在合理布局下可提升整体效率。文中构建了统一的空-水推进CFD分析框架,提出了一种跨介质推进性能定量评估方法,为跨介质机器人推进系统的布局优化与多模态协同设计提供理论参考。 展开更多
关键词 跨介质机器人 空-水双模态 cfd仿真 推进性能 尾流 多模态协同
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CFD辅助的柴油加氢裂解反应过程分子水平模拟
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作者 黄泽义 叶磊 +8 位作者 覃兴龙 田冬妮 马明轩 张雅欣 宋子杰 刘纪昌 张健 张金山 胡炳星 《石油学报(石油加工)》 北大核心 2026年第1期145-161,共17页
柴油加氢裂解工艺是炼油厂改善油品质量、提高化学品收率的典型技术。为提升柴油加氢裂解工艺应对油化市场需求变化的灵活性,采用结构导向集总(SOL)方法和计算流体力学(CFD)对柴油加氢裂解反应过程进行了分子水平的模拟与优化。依据气... 柴油加氢裂解工艺是炼油厂改善油品质量、提高化学品收率的典型技术。为提升柴油加氢裂解工艺应对油化市场需求变化的灵活性,采用结构导向集总(SOL)方法和计算流体力学(CFD)对柴油加氢裂解反应过程进行了分子水平的模拟与优化。依据气相色谱仪与全二维气相色谱-飞行时间质谱联用仪对原料柴油的分析结果,采用22个结构单元构建由1210个结构向量组成的1210行×23列分子组成矩阵。结合临氢催化反应机理,设计了34条反应规则描述柴油加氢裂解反应网络,依据阿伦尼乌斯方程计算反应速率,运用改进的Runge-Kutta法求解反应网络,建立了分子水平的柴油加氢裂解反应动力学模型。结合反应器结构与流体流动状态,采用Fluent软件模拟反应器内的三维流动和传热过程。研究表明:将CFD模拟得到的反应器内部温度场数据引入基于SOL方法的柴油加氢裂解反应动力学模型的热反馈,显著提升了模型的预测精度;与未引入CFD温度场的模型相比,引入CFD温度场的模型对产物收率、族组成分布和典型分子四氢萘的质量分数计算偏差分别降低了0.76、1.04和0.22百分点。CFD计算与分子水平反应动力学模型相结合可以模拟反应器内的温度场和流场变化,从而更为精准地反映柴油加氢裂解反应器内的分子组成分布,揭示分子转化规律,指导柴油加氢裂解反应过程的模拟与优化。 展开更多
关键词 加氢裂解 反应动力学 计算流体力学(cfd) 结构导向集总 分子管理
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Artificial intelligence-aided semi-automatic joint trace detection from textured three-dimensional models of rock mass 被引量:1
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作者 Seyedahmad Mehrishal Jineon Kim +1 位作者 Yulong Shao Jae Joon Song 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期1973-1985,共13页
It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimens... It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimensional(3D)models are relatively straightforward but time-consuming.One potential solution to enhance this process is to use machine learning algorithms to detect the 3D traces.In this study,a unique pixel-wise texture mapper algorithm generates a dense point cloud representation of an outcrop with the precise resolution of the original textured 3D model.A virtual digital image rendering was then employed to capture virtual images of selected regions.This technique helps to overcome limitations caused by the surface morphology of the rock mass,such as restricted access,lighting conditions,and shading effects.After AI-powered trace detection on two-dimensional(2D)images,a 3D data structuring technique was applied to the selected trace pixels.In the 3D data structuring,the trace data were structured through 2D thinning,3D reprojection,clustering,segmentation,and segment linking.Finally,the linked segments were exported as 3D polylines,with each polyline in the output corresponding to a trace.The efficacy of the proposed method was assessed using a 3D model of a real-world case study,which was used to compare the results of artificial intelligence(AI)-aided and human intelligence trace detection.Rosette diagrams,which visualize the distribution of trace orientations,confirmed the high similarity between the automatically and manually generated trace maps.In conclusion,the proposed semi-automatic method was easy to use,fast,and accurate in detecting the dominant jointing system of the rock mass. 展开更多
关键词 Automatic trace detection Digital joint mapping Rock discontinuities characterization three-dimensional(3D)trace network
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Dynamic modeling of a three-dimensional braided composite thin plate considering braiding directions 被引量:1
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作者 Chentong GAO Huiyu SUN +1 位作者 Jianping GU W.M.HUANG 《Applied Mathematics and Mechanics(English Edition)》 2025年第1期123-138,共16页
Currently,there are a limited number of dynamic models available for braided composite plates with large overall motions,despite the incorporation of three-dimensional(3D)braided composites into rotating blade compone... Currently,there are a limited number of dynamic models available for braided composite plates with large overall motions,despite the incorporation of three-dimensional(3D)braided composites into rotating blade components.In this paper,a dynamic model of 3D 4-directional braided composite thin plates considering braiding directions is established.Based on Kirchhoff's plate assumptions,the displacement variables of the plate are expressed.By incorporating the braiding directions into the constitutive equation of the braided composites,the dynamic model of the plate considering braiding directions is obtained.The effects of the speeds,braiding directions,and braided angles on the responses of the plate with fixed-axis rotation and translational motion,respectively,are investigated.This paper presents a dynamic theory for calculating the deformation of 3D braided composite structures undergoing both translational and rotational motions.It also provides a simulation method for investigating the dynamic behavior of non-isotropic material plates in various applications. 展开更多
关键词 three-dimensional(3D)braided composite braiding direction composite thin plate large overall motion dynamic model
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Three-dimensional models:from cell culture to Patient-Derived Organoid and its application to future liposarcoma research
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作者 SAYUMI TAHARA SYDNEY RENTSCH +4 位作者 FERNANDA COSTAS CASAL DE FARIA PATRICIA SARCHET ROMA KARNA FEDERICA CALORE RAPHAEL E.POLLOCK 《Oncology Research》 SCIE 2025年第1期1-13,共13页
Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma ... Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma pathobiology.Conventional cell culture-based research(2D cell culture)is still playing a pivotal role,while several shortcomings have been recently under discussion.In vivo,mouse models are usually adopted for pre-clinical analyses with expectations to overcome the issues of 2D cell culture.However,they do not fully recapitulate human dedifferentiated liposarcoma(DDLPS)characteristics.Therefore,three-dimensional(3D)culture systems have been the recent research focus in the cell biology field with the expectation to overcome at the same time the disadvantages of 2D cell culture and in vivo animal models and fill in the gap between them.Given the liposarcoma rarity,we believe that 3D cell culture techniques,including 3D cell cultures/co-cultures,and Patient-Derived tumor Organoids(PDOs),represent a promising approach to facilitate liposarcoma investigation and elucidate its molecular mechanisms and effective therapy development.In this review,we first provide a general overview of 3D cell cultures compared to 2D cell cultures.We then focus on one of the recent 3D cell culture applications,Patient-Derived Organoids(PDOs),summarizing and discussing several PDO methodologies.Finally,we discuss the current and future applications of PDOs to sarcoma,particularly in the field of liposarcoma. 展开更多
关键词 Cell culture LIPOSARCOMA Patient-Derived Organoid(PDO) SPHEROID three-dimensional(3D)cell culture
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