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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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WRF-CFD模式耦合的山地风电场非定常仿真方法与验证
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作者 马国林 宋翌蕾 +1 位作者 田琳琳 赵宁 《中国电机工程学报》 北大核心 2026年第2期679-690,I0019,共13页
复杂地形风电场流动具有强烈的非定常现象和多尺度特征,其准确模拟是风资源精细化评估的难点。为兼顾宏观中尺度大气环流和微观非定常流动细节,该文结合中尺度气象研究与预报(weather research and forecasting,WRF)模式和微尺度计算流... 复杂地形风电场流动具有强烈的非定常现象和多尺度特征,其准确模拟是风资源精细化评估的难点。为兼顾宏观中尺度大气环流和微观非定常流动细节,该文结合中尺度气象研究与预报(weather research and forecasting,WRF)模式和微尺度计算流体动力学(computational fluid dynamics,CFD)技术,构建一套WRF-CFD模式耦合的复杂地形风电场非定常仿真方法。以国际经典案例Askervein山和Bolund岛为验证对象,研究复杂地形流场中平均风速和湍流强度的分布特征,并简要分析复杂地形中风力机布置策略。结果表明,基于WRF-CFD模式的数值模拟结果与实验观测值有较好的一致性,且优于中尺度数值模拟结果,在选取的特征点位置,风速绝对误差均在2 m/s以内。结果可为风力机的设计、布局、载荷评估及风电场运行控制提供一定参考。 展开更多
关键词 风资源评估 风电场 复杂地形 中微尺度耦合 气象研究与预报模式 计算流体动力学
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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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Cluster globally,model locally:clusterwise modeling of nonlinear dynamics
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作者 Nan Deng Bernd R.Noack +2 位作者 Luc R.Pastur Guy Y.Cornejo Maceda Chang Hou 《Acta Mechanica Sinica》 2025年第8期45-64,共20页
Data-driven reduced-order modeling opens new avenues of understanding,predicting,controlling,and optimizing system behavior.Simple systems may have state spaces in which sparse human-interpretable dynamical systems ca... Data-driven reduced-order modeling opens new avenues of understanding,predicting,controlling,and optimizing system behavior.Simple systems may have state spaces in which sparse human-interpretable dynamical systems can be identified.This approach has been pioneered by Brunton et al.(2016,PNAS)with sparse identification of nonlinear dynamics.Complex systems,however,cannot be expected to benefit from such simple analytical descriptions.Yet,smoothness may be exploited by analytical local descriptions.In this paper,we identify a clusterwise polynomial dynamics from time-resolved snapshot data.The full state space is partitioned into clusters with a reduced-order polynomial description for each cluster and a global patching strategy.The resulting clusterwise modeling is entirely data-driven and requires no prior knowledge of the system dynamics.We illustrate the approach on the well-known chaotic Lorenz and Rössler systems,on the more challenging chaotic fluid flow dynamics of higher state-space dimensions,on a noisy electrocardiogram signal,and finally on the time evolution of the monthly sunspot number.Clusterwise modeling offers a powerful and interpretable paradigm for dynamical modeling.Nonlinear dynamics can be approximated by assembling many simple local models of different resolutions,opening new paths to understand and control intricate nonlinearities. 展开更多
关键词 Nonlinear dynamics Reduced-order modeling System identification CLUSTERING Shear flow
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Contact Dynamics Modeling and Control During the Combination Process of Air-Ground Robots
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作者 Xueying Jin Haoyuan Liu +2 位作者 Guiyu Dong Kun Xu Xilun Ding 《Chinese Journal of Mechanical Engineering》 2025年第1期306-322,共17页
In recent years,there has been a surge of interest in air-ground collaborative robotics technologies.Our research group designs a novel combination-separation air-ground robot(CSAGR),which exhibits rapid automatic com... In recent years,there has been a surge of interest in air-ground collaborative robotics technologies.Our research group designs a novel combination-separation air-ground robot(CSAGR),which exhibits rapid automatic combination and separation capabilities.During the combination process,contact effects between robots,as well as between robots and the environment,are unavoidable.Therefore,it is essential to conduct detailed and accurate modeling and analysis of the collision impact intensity and transmission pathways within the robotic system to ensure the successful execution of the combination procedure.This paper addresses the intricate surface geometries and multi-point contact challenges present in the contact regions of dual robots by making appropriate modifications to the traditional continuous contact force model and applying equivalent processing techniques.The validity of the developed model is confirmed through comparisons with results obtained from finite element analysis(FEA),which demonstrates its high fidelity.Additionally,the impact of this model on control performance is analyzed within the flight control system,thereby further ensuring the successful completion of the combination process.This research represents a pioneering application and validation of continuous contact theory in the dynamics of collisions within dual robot systems. 展开更多
关键词 Air-ground robot Combination-separation function Contact force Dynamic modeling Finite element analysis
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Evaluation of scale effects in physical modeling of combined ogee and sharp-crested weir flow using a 3D CFD model
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作者 James Zulfan Bobby Minola Ginting Ravi Anthony Tartandyo 《Water Science and Engineering》 2025年第2期225-235,共11页
Research on scale effects on flows over weirs has been conducted on a limited basis, primarily focusing on flows upstream of a single-type weir, such as ogee, broad-crested, and sharp-crested (linear and non-linear) w... Research on scale effects on flows over weirs has been conducted on a limited basis, primarily focusing on flows upstream of a single-type weir, such as ogee, broad-crested, and sharp-crested (linear and non-linear) weirs. However, the scale effects downstream of these single-type weirs have not been thoroughly investigated. This study examined the scale effects on flows over a combined weir system consisting of an ogee weir and a sharp-crested weir, both upstream and downstream, utilizing physical modeling at a 1:33.33 scale based on Froude similarity and three-dimensional (3D) computational fluid dynamics (CFD) modeling. The sharp-crested weir in this study was represented by two sluice gates that remain closed and submerged during flood events. The experimental data confirmed that the equivalent discharge coefficients of the combined weir system behaved similarly to those of a sharp-crested weir across various H/P (where H is the total head, and P is the weir height) values. However, scale effects on the discharge rating curve due to surface tension and viscosity could only be minimized when H/P > 0.4, Re > 26 959, and We > 240 (where Re and We are the Reynolds and Weber numbers, respectively), provided that the water depth exceeded 0.042 m above the crest. Additionally, Re greater than 4 × 104 was necessary to minimize scale effects caused by viscosity in flows in the spillway channel and stilling basin (with baffle blocks). The limiting criteria aligned closely with existing literature. This study offers valuable insights for practical applications in hydraulic engineering in the future. 展开更多
关键词 3D cfd Ogee weir Physical modeling Sharp-crested weir Sluice gate Scale effects
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Enhancing hydrogel predictive modeling:an augmented neural network approach for swelling dynamics in pH-responsive hydrogels
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作者 M.A.FARAJI M.ASKARI-SEDEH +1 位作者 A.ZOLFAGHARIAN M.BAGHANI 《Applied Mathematics and Mechanics(English Edition)》 2025年第9期1787-1808,共22页
The pH-sensitive hydrogels play a crucial role in applications such as soft robotics,drug delivery,and biomedical sensors,as they require precise control of swelling behaviors and stress distributions.Traditional expe... The pH-sensitive hydrogels play a crucial role in applications such as soft robotics,drug delivery,and biomedical sensors,as they require precise control of swelling behaviors and stress distributions.Traditional experimental methods struggle to capture stress distributions due to technical limitations,while numerical approaches are often computationally intensive.This study presents a hybrid framework combining analytical modeling and machine learning(ML)to overcome these challenges.An analytical model is used to simulate transient swelling behaviors and stress distributions,and is confirmed to be viable through the comparison of the obtained simulation results with the existing experimental swelling data.The predictions from this model are used to train neural networks,including a two-step augmented architecture.The initial neural network predicts hydration values,which are then fed into a second network to predict stress distributions,effectively capturing nonlinear interdependencies.This approach achieves mean absolute errors(MAEs)as low as 0.031,with average errors of 1.9%for the radial stress and 2.55%for the hoop stress.This framework significantly enhances the predictive accuracy and reduces the computational complexity,offering actionable insights for optimizing hydrogel-based systems. 展开更多
关键词 transient swelling pH-responsive hydrogel neural network data-driven model hydration and stress dynamics
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CFD Simulation of Passenger Car Aerodynamics and Body Parameter Optimization
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作者 Jichao Li Xuexin Zhu +2 位作者 Cong Zhang Shiwang Dang Guang Chen 《Fluid Dynamics & Materials Processing》 2025年第9期2305-2329,共25页
The rapid advancement of technology and the increasing speed of vehicles have led to a substantial rise in energy consumption and growing concern over environmental pollution.Beyond the promotion of new energy vehicle... The rapid advancement of technology and the increasing speed of vehicles have led to a substantial rise in energy consumption and growing concern over environmental pollution.Beyond the promotion of new energy vehicles,reducing aerodynamic drag remains a critical strategy for improving energy efficiency and lowering emissions.This study investigates the influence of key geometric parameters on the aerodynamic drag of vehicles.A parametric vehicle model was developed,and computational fluid dynamics(CFD)simulations were conducted to analyse variations in the drag coefficient(C_(d))and pressure distribution across different design configurations.The results reveal that the optimal aerodynamic performance—characterized by a minimized drag coefficient—is achieved with the following parameter settings:engine hood angle(α)of 15°,windshield angle(β)of 25°,rear window angle(γ)of 40°,rear upwards tail lift angle(θ)of 10°,ground clearance(d)of 100 mm,and side edge angle(s)of 5°.These findings offer valuable guidance for the aerodynamic optimization of vehicle body design and contribute to strategies aimed at energy conservation and emission reduction in the automotive sector. 展开更多
关键词 Automotive aerodynamic characteristics flow field aerodynamic drag drag reduction optimization cfd(computational fluid dynamics)
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CFD Modeling to Evaluate User Safety by Using Flame Retardants in Asphalt Road Pavements during Large Tunnel Fires
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作者 Ciro Caliendo Isidoro Russo Gianluca Genovese 《Computer Modeling in Engineering & Sciences》 2025年第7期693-715,共23页
Road pavements in tunnels are usually made of asphalt mixtures,which,unfortunately,are flammable materials.Hence,this type of pavement could release heat,and more specifically smoke,in the event of a tunnel fire,there... Road pavements in tunnels are usually made of asphalt mixtures,which,unfortunately,are flammable materials.Hence,this type of pavement could release heat,and more specifically smoke,in the event of a tunnel fire,thereby worsening the environmental conditions for human health.Extensive research has been conducted in recent years to enhance the fire reaction of traditional asphalt mixtures for the road pavements used in tunnels.The addition of the Flame Retardants(FRs)in conventional asphalt mixtures appears to be promising.Nevertheless,the potential effects of the FRs in terms of the reduction in consequences on tunnel users in the event of a large fire do not seem to have been sufficiently investigated by using fluid dynamics analysis as a computational tool.Given this gap of knowledge,this article aims to quantitatively evaluate whether the use of flame-retarded asphalt mixtures,as opposed to traditional ones without FRs,might mitigate the adverse effects on the safety of evacuees and fire brigade by performing numerical analyses in the case of a tunnel fire.To achieve this goal,3D Computational Fluid Dynamics(CFD)models,which were executed using the Fire Dynamics Simulator(FDS)tool,were established in the case of a major fire of a Heavy Goods Vehicle(HGV)characterized by a maximum Heat Release Rate(HRRmax)of 100 MW.The people evacuation process was also simulated,and the Evac tool was used.Compared to the traditional asphalt pavements without FRs,the simulation findings indicated that the addition of the FRs causes a reduction in CO and CO_(2)levels in the tunnel during the aforementioned fire,with a minor number of evacuees being exposed to the risk of incapacity to self-evacuate,as well as certain safety benefits for the operability of the firefighters entering the tunnel downstream of the fire when the tunnel is naturally ventilated. 展开更多
关键词 Asphalt pavement combustion flame retardants road tunnel fire cfd modeling user safety operability of fire brigade
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基于CFD模拟的纵向通风哺乳猪舍气流与温度的优化研究
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作者 张校军 徐云政 +1 位作者 陈昭辉 赵晓冬 《家畜生态学报》 北大核心 2026年第1期88-95,共8页
为解决纵向通风哺乳母猪舍存在气流和温度分布不均匀的问题,该文通过计算流体力学(Computational Fluid Dynamics,CFD)模拟技术,研究了导流板长度为0.4~0.8 m和间距为2~6 m的不同工况下对哺乳母猪舍不同区域风速、温度以及舍内气流均匀... 为解决纵向通风哺乳母猪舍存在气流和温度分布不均匀的问题,该文通过计算流体力学(Computational Fluid Dynamics,CFD)模拟技术,研究了导流板长度为0.4~0.8 m和间距为2~6 m的不同工况下对哺乳母猪舍不同区域风速、温度以及舍内气流均匀度的影响。哺乳猪舍模型通过现场试验进行验证。结果表明:(1)出风口区域的风速随着导流板间距的减少、长度的增加而增加,导流板间距为2 m、长度为0.8 m工况下最大增幅为0.6 m/s。(2)出风口区域的温度随着导流板间距的减少、长度的增加而降低,导流板间距为2 m、长度为0.8 m工况下最大减幅为0.8℃。(3)导流板可增加母猪上方区域气流的均匀性,随导流板间距的减少、长度的增加而提高,在距离地面0.8 m高度的气流不均匀系数从0.8降至0.15。(4)在该研究条件下,导流板长度和间距与Y=0.8 m平面风速呈线性回归关系,回归方程为y=0.419 x_(1)-0.01x_(2)+0.548(x_(1)表示导流板长度,x_(2)表示导流板间距,R^(2)=0.99)。该研究通过CFD模拟定量分析了纵向通风哺乳猪舍内气流和温度的分布以及安装不同长度和间距的导流板对舍内气流和温度影响,为纵向通风哺乳猪舍内气流和温度优化提供了理论依据。 展开更多
关键词 计算流体力学 纵向通风 哺乳猪舍 气流 温度
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Photometric modeling of ejecta for evaluating defensive Kinetic impacts on asteroids
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作者 XiaoYu Sun ZhiJun Song +4 位作者 XiaoTao Guo XiaoJing Zhang Yuri Skorov Yang Yu He Zhang 《Earth and Planetary Physics》 2026年第1期205-221,共17页
Kinetic impact is the most practical planetary-defense technique,with momentum-transfer efficiency central to deflection design.We present a Monte Carlo photometric framework that couples ejecta sampling,dynamical evo... Kinetic impact is the most practical planetary-defense technique,with momentum-transfer efficiency central to deflection design.We present a Monte Carlo photometric framework that couples ejecta sampling,dynamical evolution,and image synthesis to compare directly with HST,LICIACube,ground-based and Lucy observations of the DART impact.Decomposing ejecta into(1)a highvelocity(~1600 m/s)plume exhibiting Na/K resonance,(2)a low-velocity(~1 m/s)conical component shaped by binary gravity and solar radiation pressure,and(3)meter-scale boulders,we quantify each component’s mass and momentum.Fitting photometric decay curves and morphological evolution yields size-velocity distributions and,via scaling laws,estimates of Dimorphos’bulk density,cratering parameters,and cohesive strength that agree with dynamical constraints.Photometric ejecta modeling therefore provides a robust route to constrain momentum enhancement and target properties,improving predictive capability for kinetic-deflection missions. 展开更多
关键词 Kinetic impact DART mission ejecta dynamics photometric modeling
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A review on research of system dynamics and multi-source fault diagnosis of key components in high-speed train
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作者 Baosen Wang Yongqiang Liu +4 位作者 Qilan Li Min Wang Qiaoying Ma Yingying Liao Shaopu Yang 《Chinese Journal of Mechanical Engineering》 2026年第1期496-507,共12页
As China's high-speed railway technology advances,high-speed trains have emerged as a pivotal mode of transportation,instrumental in facilitating passenger and freight mobility while fostering robust regional eco-... As China's high-speed railway technology advances,high-speed trains have emerged as a pivotal mode of transportation,instrumental in facilitating passenger and freight mobility while fostering robust regional eco-nomic and trade interactions.Nonetheless,the safety of train operations remains a paramount concern,prompting extensive research into the dynamic behavior of critical components,which is essential to ensuring seamless and secure transportation services.This article commences by comprehensively reviewing the current landscape and evolutionary trajectory of dynamic model analysis for both traditional bearings and axle box bearings.Emphasis is placed on elucidating the profound influence of diverse bearing fault types on the system's kinematic state,alongside delving into the research methodologies employed in developing multi-physics field coupling models.Subsequently,it expounds on the content of investigations focusing on various wheel and track impairments,grounded in the dynamic modeling of the bearing vehicle coupling system.Concurrently,the intricate interplay between wheel-rail excitation and axle box bearing faults on the system's performance is elucidated.Concludingly,the article underscores the inadequacy of current multi-source fault diagnosis meth-odologies in tackling the intricacies of complex train operating environments,thereby highlighting its sig-nificance as a pressing and vital research agenda for the future. 展开更多
关键词 High-speed train Axle box bearing Dynamic model Wheel rail excitation Multi-source fault
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基于CFD的直翼舵桨结构参数对水动力特性的影响
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作者 温小飞 胡昌龙 +1 位作者 黄佳林 肖惟起 《船舶工程》 北大核心 2026年第3期13-24,共12页
[目的]为了分析直翼舵桨推进器结构参数选型和性能优化方面存在的不足,[方法]以FSDJ-400RE-C型直翼舵桨为研究对象,采用基于计算流体力学(CFD)数值模拟方法构建数学模型,对其水动力性能进行仿真分析。通过对进速系数J取值为0~2.4时的数... [目的]为了分析直翼舵桨推进器结构参数选型和性能优化方面存在的不足,[方法]以FSDJ-400RE-C型直翼舵桨为研究对象,采用基于计算流体力学(CFD)数值模拟方法构建数学模型,对其水动力性能进行仿真分析。通过对进速系数J取值为0~2.4时的数值仿真结果与试验数据进行对比,验证构建的数学模型的准确性,其中:J=2.0工况下的效率偏差仅为6.6285%。在此基础上,以J=2.0为代表工况,对桨叶长度、弦长和厚度等主要结构参数的压力场、速度场和水动力特性曲线进行对比分析,并以单一参数下桨叶水动力最优为条件进行参数组合仿真计算。[结果]结果表明:当桨叶长度为1260 mm、弦长为510 mm、厚度为60 mm时,单参数下的水动力性能最优,但最优参数组合并非简单的叠加最优;以桨叶长度L为基准,当桨叶弦长C与L的比值为0.405、桨叶厚度T与C的比值为0.118时,直翼舵桨的水动力特性达到最佳状态。[结论]研究成果可供直翼舵桨的水动力性能预报、桨叶机构设计和优化参考。 展开更多
关键词 直翼舵桨 计算流体力学(cfd) 水动力特性 结构参数
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Face-Pedestrian Joint Feature Modeling with Cross-Category Dynamic Matching for Occlusion-Robust Multi-Object Tracking
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作者 Qin Hu Hongshan Kong 《Computers, Materials & Continua》 2026年第1期870-900,共31页
To address the issues of frequent identity switches(IDs)and degraded identification accuracy in multi object tracking(MOT)under complex occlusion scenarios,this study proposes an occlusion-robust tracking framework ba... To address the issues of frequent identity switches(IDs)and degraded identification accuracy in multi object tracking(MOT)under complex occlusion scenarios,this study proposes an occlusion-robust tracking framework based on face-pedestrian joint feature modeling.By constructing a joint tracking model centered on“intra-class independent tracking+cross-category dynamic binding”,designing a multi-modal matching metric with spatio-temporal and appearance constraints,and innovatively introducing a cross-category feature mutual verification mechanism and a dual matching strategy,this work effectively resolves performance degradation in traditional single-category tracking methods caused by short-term occlusion,cross-camera tracking,and crowded environments.Experiments on the Chokepoint_Face_Pedestrian_Track test set demonstrate that in complex scenes,the proposed method improves Face-Pedestrian Matching F1 area under the curve(F1 AUC)by approximately 4 to 43 percentage points compared to several traditional methods.The joint tracking model achieves overall performance metrics of IDF1:85.1825%and MOTA:86.5956%,representing improvements of 0.91 and 0.06 percentage points,respectively,over the baseline model.Ablation studies confirm the effectiveness of key modules such as the Intersection over Area(IoA)/Intersection over Union(IoU)joint metric and dynamic threshold adjustment,validating the significant role of the cross-category identity matching mechanism in enhancing tracking stability.Our_model shows a 16.7%frame per second(FPS)drop vs.fairness of detection and re-identification in multiple object tracking(FairMOT),with its cross-category binding module adding aboute 10%overhead,yet maintains near-real-time performance for essential face-pedestrian tracking at small resolutions. 展开更多
关键词 Cross-category dynamic binding joint feature modeling face-pedestrian association multi object tracking occlusion robustness
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基于CFD的深海轮式ROV水动力分析
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作者 白传宏 李德威 《船舶工程》 北大核心 2026年第1期168-175,共8页
[目的]为了更好实现对深海资源探测以及生物样品采集,[方法]从遥控水下机器人(ROV)的使用要求与整体结构出发,设计一款可在6000 m深处海洋作业的爬行兼浮游复合式机器人,基于计算流体力学(CFD)的数值计算分析方法对ROV的水动力特性进行... [目的]为了更好实现对深海资源探测以及生物样品采集,[方法]从遥控水下机器人(ROV)的使用要求与整体结构出发,设计一款可在6000 m深处海洋作业的爬行兼浮游复合式机器人,基于计算流体力学(CFD)的数值计算分析方法对ROV的水动力特性进行数值仿真,并基于整体式水动力模型进行水动力参数求解。[结果]结果表明:该ROV满足克服海下水阻力的要求,拟合得到的水动力系数可为ROV整体结构设计的优化、控制系统的设计提供数据支持。[结论]研究结果可为ROV的设计提供一定参考。 展开更多
关键词 遥控水下机器人(ROV) 网格边界条件 水动力分析 计算流体力学(cfd)
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基于CFD-DEM耦合的碾米颗粒运动模拟与方法研究
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作者 杨勇 周龙 +2 位作者 范吉军 余南辉 李园 《食品与机械》 北大核心 2026年第1期64-71,共8页
[目的]针对卧式碾米机在碾米过程中造成颗粒破碎和过碾的问题,提出通过改变吸风气流方向提高糙米颗粒的碾磨质量。[方法]采用CFD-DEM耦合方法,分别对上吸风10 m/s、下吸风5 m/s和无风速3种状态进行数值仿真分析,并通过物理样机碾磨试验... [目的]针对卧式碾米机在碾米过程中造成颗粒破碎和过碾的问题,提出通过改变吸风气流方向提高糙米颗粒的碾磨质量。[方法]采用CFD-DEM耦合方法,分别对上吸风10 m/s、下吸风5 m/s和无风速3种状态进行数值仿真分析,并通过物理样机碾磨试验验证仿真结果。[结果]随着气流方向由上吸风转变到下吸风,颗粒沿Y轴的上升速度vy及三轴合成平均速度v整体降低,同层段位置处上吸风颗粒速度vy大于下吸风的,在碾白室中下部处明显观察到上吸风颗粒平均速度v大于下吸风颗粒的,碾磨区域内颗粒运动能力的差异导致容易过碾和破损区域的受力情况明显不同,颗粒运动能力强时碾白室底部颗粒受到的挤压力减小,颗粒运动能力弱时碾白室底部颗粒受到的挤压力增大;颗粒翻滚角速度在上吸风的作用下,对比无风速和下吸风效果增强;每种状态下3次的物理试验结果,上吸风10 m/s、无风速和下吸风5 m/s的碾磨度平均值分别为1.90%,2.20%,2.78%,破损率平均值分别为0.37%,0.46%,0.60%。[结论]上吸风状态下颗粒碾磨过程中的流动和受力特性优于无风速和下吸风的情况;上吸风比无风速和下吸风的碾磨度和破碎率明显下降。 展开更多
关键词 碾米颗粒 cfd-DEM 颗粒流动 多孔介质模型
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基于CFD-PBM耦合模型的搅拌槽中气体分散特性研究
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作者 李凯旋 李政权 +3 位作者 张博群 王贻得 石昊宇 周宗彦 《中国有色冶金》 北大核心 2026年第1期113-124,共12页
在气液搅拌的混合与分散过程中,气泡的尺寸和分布不仅决定气泡的上升速度和气体在液相中的停留时间,还直接影响含气率及气液接触面积。诸多学者采用计算流体动力学(CFD)研究了气泡尺寸分布、气体含量和液体速度,但均没有考虑气泡聚并和... 在气液搅拌的混合与分散过程中,气泡的尺寸和分布不仅决定气泡的上升速度和气体在液相中的停留时间,还直接影响含气率及气液接触面积。诸多学者采用计算流体动力学(CFD)研究了气泡尺寸分布、气体含量和液体速度,但均没有考虑气泡聚并和破碎的影响。群体平衡模型(PBM)重建了气泡尺寸分布,构建了气泡破碎和聚并的核函数,PBM与CFD结合,可以在搅拌罐等工艺设备中获得相当准确的气泡尺寸。本文采用CFD-PBM耦合模型,研究搅拌槽内气液分散过程的流体动力学,探究转速和气体流量对气泡尺寸分布、流场、数量浓度及气含率的影响,得到以下主要结论。该模型精度高于Basavarajappa的预测,且模拟结果对比最大误差不超过10%,能很好的预测气泡尺寸分布;搅拌转速显著影响气液混合效率,高转速(400 r/min)下气泡尺寸更小且分布均匀,气液传质性能显著提升;低气体流量(0.5 vvm)下,气泡生成量较少且分布不均匀,适当增加气体流量(0.7 vvm)有助于延长气泡滞留时间,但过高流量(0.9 vvm)可能导致气泡聚并和传质效率下降;高转速(400 r/min)下,搅拌桨叶片背液面区域会出现明显的气穴现象,这是由局部负压导致气体汇聚形成稳定的气腔,对搅拌效率和气液分散效果产生不利影响;通过合理调控转速和叶轮设计,可以减轻气穴现象所带来的不利影响,从而进一步提升搅拌效率和气体分散效果。实际生产中,可以通过优化搅拌速度与气体流量,来改善气泡分布和气液混合效果。 展开更多
关键词 搅拌槽 气液两相 cfd-PBM耦合模型 分散特性 气泡分布
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基于CFD-DEM方法的高炉炉料轨迹落点预测
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作者 何潺 刘丕亮 +1 位作者 林帅辉 吴博 《冶金能源》 北大核心 2026年第1期62-69,共8页
针对当前高炉炉料落点预测的不足,文章采用CFD-DEM方法分析高炉炉料轨迹和落点位置,并利用程树森等提出的数学模型验证CFD-DEM模型的准确性。该方法全面考虑多种影响因素,包括科里奥利力、煤气流量、溜槽的旋转速度和倾角等,直观和精准... 针对当前高炉炉料落点预测的不足,文章采用CFD-DEM方法分析高炉炉料轨迹和落点位置,并利用程树森等提出的数学模型验证CFD-DEM模型的准确性。该方法全面考虑多种影响因素,包括科里奥利力、煤气流量、溜槽的旋转速度和倾角等,直观和精准地再现炉料在高炉内的运动过程。结果表明:当溜槽转速为1.05 rad/s时,科里奥利力对焦炭和矿石落点的影响分别达到28%和22%,煤气流非均匀性使焦炭和矿石的落点半径外移2.74%和3.87%。精准预测料流轨迹落点必须综合考虑科里奥利力和煤气流的影响。与数学模型对比,CFD-DEM模型对焦炭和矿石落点半径预测均方根误差分别为0.060 m和0.055 m,最大相对偏差不超过5%,与数学模型预测结果几乎一致,因此能够准确预测高炉炉料轨迹落点,为后续高炉布料操作提供新的理论依据。 展开更多
关键词 无料钟炉顶高炉 cfd-DEM 数学模型验证 科里奥利力 气固耦合
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基于CFD的化工反应器流场优化研究
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作者 孙永伟 《化工管理》 2026年第3期98-101,共4页
化工反应器在化学工程中具有重要作用,但传统反应器常存在流场不均、死区及流动短路等问题,这些问题影响了反应效率并导致能量浪费。可借助计算流体动力学(computational fluid dynamics,CFD)技术,优化化工反应器流场。该方法通过优化... 化工反应器在化学工程中具有重要作用,但传统反应器常存在流场不均、死区及流动短路等问题,这些问题影响了反应效率并导致能量浪费。可借助计算流体动力学(computational fluid dynamics,CFD)技术,优化化工反应器流场。该方法通过优化反应器几何结构、调整流动控制策略并选择合适的湍流模型,提高流场均衡性与湍流强度调节效力。研究结果表明,优化后的反应器反应物转化率和产物选择性显著提升。此外,优化方案有效降低了能量消耗,提高了反应器的整体运行效率。研究为化工反应器的设计与优化提供了理论依据和技术支持。 展开更多
关键词 计算流体动力学 化工反应器 流场优化 湍流模型 传质效率
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煤矿通风应急响应示踪气体与CFD模拟研究
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作者 王剑亮 《煤炭科技》 2026年第1期45-49,共5页
在煤矿突发事件应急处置过程中,存在救援人员无法直接进入事故地点的情况,此时通过远程手段快速准确分析矿井通风系统运行状态,助力矿山救援队伍做出科学决策至关重要。为此,结合示踪气体技术和计算流体动力学(CFD)建模方法,通过向煤矿... 在煤矿突发事件应急处置过程中,存在救援人员无法直接进入事故地点的情况,此时通过远程手段快速准确分析矿井通风系统运行状态,助力矿山救援队伍做出科学决策至关重要。为此,结合示踪气体技术和计算流体动力学(CFD)建模方法,通过向煤矿通风系统释放特定示踪气体,利用CFD模型对矿井内的气流流动进行数值模拟,建立4种通风破坏场景以模拟不同程度或类型的通风系统失效情况,并将模型预测结果与现场实验数据进行了对比验证,确保模型分析的有效性和准确性。实验与模型分析结果显示,结合示踪气体剖面的直接观测与CFD模型的数值模拟,能够有效识别矿井通风系统的变化特征,有助于提升矿井应急救援的响应速度和决策质量。 展开更多
关键词 矿井通风 示踪气体 cfd建模
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