Journal of Wind Engineering and Industrial Aerodynamics最新文献_第9页

Large eddy simulation of the flow around a high-rise building with special focus on the two-points two-times second order statistics of the velocity field 高层建筑周围流动的大涡度模拟，特别关注速度场的两点两倍二阶统计量

IF 4.2 2区工程技术 Q1 ENGINEERING, CIVIL

Journal of Wind Engineering and Industrial Aerodynamics

Pub Date : 2024-10-25 DOI: 10.1016/j.jweia.2024.105914

Mohanad Elagamy , Nishchay Tiwari , Cristobal Gallego-Castillo , Alvaro Cuerva-Tejero , Oscar Lopez-Garcia , Sergio Avila-Sanchez

Comprehending the wind characteristics in urban environments is crucial to ensure optimal performance and structural integrity of wind turbines operating in urban areas. This study aims to provide a deeper insight into wind characteristics over high-rise buildings rooftop. The impact of a high-rise building configuration on the turbulent wind field characteristics is analyzed, by means of large eddy simulations of a reference wind tunnel experiment. Special attention is paid to the analysis of the second order statistics of the turbulent velocity components, as they are crucial inputs for generating synthetic urban wind fields for wind turbine aeroelastic simulations. A Spectral Representation Method is applied to generate the desired turbulent inflow represented in the experiment study. The correspondence between the predicted statistics and the experimental values of the velocity components over the rooftop reinforces the idea about the practical viability of large eddy simulation to provide atmospheric turbulence information in the urban environment required to characterize the behavior of wind systems operating in that environment. Additionally, the two-points two-times second order statistics are significantly affected by the presence of the high-rise building, especially when those statistics involve at least a point within the recirculation bubble region.

了解城市环境中的风力特征对于确保在城市地区运行的风力涡轮机的最佳性能和结构完整性至关重要。本研究旨在深入探讨高层建筑屋顶的风特性。通过对参考风洞实验进行大涡模拟，分析了高层建筑配置对湍流风场特性的影响。研究特别关注湍流速度分量的二阶统计量分析，因为这些分量是为风轮机气动弹性模拟生成合成城市风场的关键输入。应用频谱表示法生成实验研究中所需的湍流流入。屋顶上的速度分量的预测统计与实验值之间的对应关系加强了大涡流模拟的实用性，它可以提供城市环境中的大气湍流信息，以描述在该环境中运行的风力系统的行为特征。此外，两点两次二阶统计受高层建筑的影响很大，特别是当这些统计至少涉及再循环气泡区域内的一个点时。

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引用次数: 0

Characterizing surface pressure and wind fields of typhoons approaching Hong Kong 接近香港的台风的表面气压和风场特征

IF 4.2 2区工程技术 Q1 ENGINEERING, CIVIL

Journal of Wind Engineering and Industrial Aerodynamics

Pub Date : 2024-10-25 DOI: 10.1016/j.jweia.2024.105934

Feng Hu , Junyi He , Zhifei Liu , Qiusheng Li , Pak-Wai Chan

In this paper, 17 severe typhoons that have affected Hong Kong are simulated using an advanced numerical atmospheric simulation system - Weather Research and Forecasting model (WRF). The simulated surface pressure and wind fields of these typhoons are validated against a wide range of field observations. Then azimuth-dependent models for the radius of maximum winds and the Holland parameter are established statistically at the surface level. It is observed that the shape parameter of the Holland pressure model is smaller at the surface than that at the gradient level. And the Holland wind field model cannot well reproduce the simulated radial wind profiles due to the complexities of nonuniform surface conditions and typhoon dynamics. It is found that the modified Rankine model provides satisfactory estimates of typhoon wind speeds in Hong Kong. Additionally, wind field asymmetries of typhoons approaching Hong Kong are highly correlated with the typhoon track velocity, vertical wind shear and the angle between them. The proposed statistical models and identified characteristics of wind field asymmetries of typhoons will provide useful information for rapidly assessing typhoon wind hazards.

本文利用先进的数值大气模拟系统--天气研究和预报模式（WRF），模拟了 17 个影响香港的强台风。这些台风的模拟表面气压和风场与大量实地观测数据进行了验证。然后，从统计角度建立了地表最大风半径和霍兰参数的方位角模型。结果表明，地表霍兰压力模型的形状参数小于梯度参数。由于非均匀表面条件和台风动力学的复杂性，荷兰风场模型不能很好地再现模拟的径向风廓线。研究发现，修正的朗肯模型对香港台风风速的估计令人满意。此外，接近香港的台风的风场不对称性与台风路径速度、垂直风切变和它们之间的角度高度相关。建议的统计模型和确定的台风风场不对称特征将为快速评估台风风灾提供有用信息。

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引用次数: 0

Flow field analysis of self-sustained flutter of a wide-slotted bridge deck 宽槽桥面自持飘移的流场分析

IF 4.2 2区工程技术 Q1 ENGINEERING, CIVIL

Journal of Wind Engineering and Industrial Aerodynamics

Pub Date : 2024-10-22 DOI: 10.1016/j.jweia.2024.105927

Jinlin Xia , Gregory A. Kopp , Yaojun Ge

This study delves into the flutter mechanism of a 5,000 m bridge with a wide-slotted deck, finding that the motion is self-sustained and not violently destructive. The system damping ratio is not fixed, and only one stable orbit exists. High-resolution PIV experiments at an experimental wind speed of 10.5 m/s measured the static and dynamic flow fields on the windward and leeward decks. The static results showed leading-edge separation on the windward deck within the reference range, while separation on the leeward deck was difficult to observe. Dynamic testing identified instantaneous vortices around the windward/leeward deck at each phase, with no signs of vortices in the wind speed vectors at all phases after phase-averaging, indicating that the vortex drift hypothesis is not valid. The analysis of the streamline pattern revealed periodic variations in leading-edge separation size and reattachment length on the windward deck during the vibration process, while the leeward deck showed consistently inconspicuous changes. Further examination uncovered a peculiar behavior in the horizontal wind speed profile on the leeward deck during the vibration process, attributed to dynamic changes in the height difference between the windward and leeward decks during flutter. The study suggests that the unusual wind speed profile on the leeward deck is caused by the dynamic changes in height difference between the windward and leeward decks during the flutter process, resulting in additional wind loading. These findings shed light on the complex dynamics of bridge flutter and have implications for the design and maintenance of long-span bridges.

本研究深入探讨了一座 5000 米宽槽桥面的扑翼机理，发现其运动是自持的，并不具有剧烈的破坏性。系统阻尼比不固定，只存在一个稳定轨道。在 10.5 米/秒的实验风速下进行的高分辨率 PIV 实验测量了迎风面和背风面的静态和动态流场。静态结果显示，迎风甲板上的前缘分离在参考范围内，而背风甲板上的分离难以观察到。动态测试在每个阶段都发现了迎风/背风甲板周围的瞬时涡流，而在阶段平均后，所有阶段的风速矢量中都没有涡流迹象，这表明涡流漂移假说不成立。对流线模式的分析表明，在振动过程中，迎风甲板上的前缘分离尺寸和重新连接长度会发生周期性变化，而背风甲板上的变化一直不明显。进一步研究发现，在振动过程中，背风甲板上的水平风速剖面有一种奇特的行为，这归因于扑翼过程中迎风甲板和背风甲板之间高度差的动态变化。研究表明，背风甲板上的异常风速剖面是由飘动过程中迎风甲板和背风甲板之间高度差的动态变化引起的，从而导致额外的风荷载。这些发现揭示了桥梁飘移的复杂动态，对大跨度桥梁的设计和维护具有重要意义。

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引用次数: 0

Dot-array porous medium model for windscreen and its simulation accuracy analysis 挡风玻璃的点阵多孔介质模型及其仿真精度分析

IF 4.2 2区工程技术 Q1 ENGINEERING, CIVIL

Journal of Wind Engineering and Industrial Aerodynamics

Pub Date : 2024-10-19 DOI: 10.1016/j.jweia.2024.105921

Deqing Zhu (朱德庆) , Tingguo Chen (陈廷国) , Chengjiao Ren (任珵娇) , Ke Wang (王可)

Porous medium models have long been prevalent numerical computation tools. Although they exhibit swift computational speed, their accuracy in simulating windscreen perforation structures is challenged. This paper introduces the innovative dot-array porous medium (DAPM) model, which accurately portrays the perforation structure and material characteristics of a windscreen by establishing virtual holes on the porous medium. Not only does it simplify modeling by eliminating complex perforation processes, but it also adeptly simulates the flow behavior of the windscreen. The comprehensive comparison between the DAPM model and the physical mesh model, traditional porous medium model, as well as wind tunnel test results, demonstrates that the DAPM model not only possesses rapid computational speed but also delivers outstanding precision in results. In terms of velocity distribution, vortex distribution, and flow intensity in the flow field, the model indicates a high level of accuracy, clearly exceeding that of the porous medium model. Moreover, the DAPM model showcases high versatility and adjustability in practical applications. By adjusting dimension parameters, it demonstrates the capability to precisely simulate any windscreen with holes arranged in a matrix pattern. This research provides an efficient and reliable tool for the numerical simulation of windscreens, with broad application prospects.

长期以来，多孔介质模型一直是流行的数值计算工具。虽然它们的计算速度很快，但在模拟挡风玻璃穿孔结构方面的准确性却受到了挑战。本文介绍了创新的点阵多孔介质（DAPM）模型，该模型通过在多孔介质上建立虚拟孔，准确地描绘了挡风玻璃的穿孔结构和材料特性。它不仅省去了复杂的穿孔过程，简化了建模，还能巧妙地模拟挡风玻璃的流动行为。DAPM 模型与物理网格模型、传统多孔介质模型以及风洞试验结果的综合比较表明，DAPM 模型不仅计算速度快，而且结果精度高。就流场中的速度分布、涡流分布和流动强度而言，该模型的精确度很高，明显超过了多孔介质模型。此外，DAPM 模型在实际应用中还具有很高的通用性和可调整性。通过调整尺寸参数，该模型能够精确模拟任何具有矩阵排列孔洞的挡风玻璃。这项研究为挡风玻璃的数值模拟提供了一种高效可靠的工具，具有广阔的应用前景。

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引用次数: 0

Wind-induced response and control criterion of the double-layer cable support photovoltaic module system 双层电缆支撑光伏组件系统的风致响应和控制标准

IF 4.2 2区工程技术 Q1 ENGINEERING, CIVIL

Journal of Wind Engineering and Industrial Aerodynamics

Pub Date : 2024-10-19 DOI: 10.1016/j.jweia.2024.105928

Yunqiang Wu , Yue Wu , Ying Sun , Xiaoying Sun

The cable support photovoltaic module system has obvious characteristics of wind-induced vibration. In order to study the wind-induced vibration response characteristics and mechanism of the double-cable support photovoltaic module systems, and further discuss the stiffness control criterion. The wind-induced vibration response of a new type of cable-truss support photovoltaic module system with a span of 35m is studied through the aeroelastic wind tunnel test. Firstly, the scaled aeroelastic test model was established to meet the aeroelastic test requirements. Then, the effects of wind direction, PV module inclination angle, and stability cable initial prestress on the wind-induced vibration response characteristics under uniform flow and turbulent field are studied. Finally, the wind-induced vibration response mechanism and stiffness control criterion are discussed. The results show that the increase of inclination angle will lead to a decrease in critical wind speed, the 0° wind direction is the most unfavorable, and the increase of initial prestress can increase the critical wind speed but is inefficient. The critical wind speed under the turbulent flow field is about 30% higher than that of the uniform flow field. The instability vibration is the result of multi-mode coupled vibration of vertical bending and torsion. It is suggested that the stiffness control criterion is more appropriate as 1/100. The research results are of great significance for the design and application of the cable support photovoltaic module system.

缆索支撑光伏组件系统具有明显的风致振动特征。为了研究双索面支撑光伏组件系统的风致振动响应特性和机理，并进一步探讨刚度控制准则。通过气动弹性风洞试验研究了跨度为 35m 的新型索桁架支撑光伏组件系统的风致振动响应。首先，建立了符合气动弹性试验要求的比例气动弹性试验模型。然后，研究了风向、光伏组件倾角和稳定索初始预应力对均匀流和湍流场下风致振动响应特性的影响。最后，讨论了风致振动响应机理和刚度控制准则。结果表明，倾角增大会导致临界风速减小，0°风向最不利，增大初始预应力可提高临界风速，但效率较低。湍流流场下的临界风速比均匀流场下的临界风速高出约 30%。失稳振动是垂直弯曲和扭转的多模耦合振动的结果。建议采用 1/100 的刚度控制标准更为合适。该研究成果对电缆支撑光伏组件系统的设计和应用具有重要意义。

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引用次数: 0

Assessment of turbulence model effects on WRF-LES of separated turbulent flows past a 3D hill 评估湍流模型对 WRF-LES 分离湍流流经三维山丘的影响

IF 4.2 2区工程技术 Q1 ENGINEERING, CIVIL

Journal of Wind Engineering and Industrial Aerodynamics

Pub Date : 2024-10-17 DOI: 10.1016/j.jweia.2024.105910

Yujiang Shi , Tao Tao , Haokai Wu , Yao-Ran Chen , Zhaolong Han , Dai Zhou , Wen-Li Chen , Yong Cao

Compared to traditional CFD models, weather research and forecasting model (WRF) can more realistically reproduce complex spatio-temporally varying wind fields under extreme weather disasters like typhoon. However, the large-eddy simulation mode of WRF (WRF-LES) to predict engineering-scale turbulence has yet to be clarified in terms of different turbulence models. This study selected a three-dimensional hill as the research object. We focus on separated flow past a 3D hill to systematically revisit the influence of four turbulence models (SMAG, TKE, NBA1, NBA2). The results show that four classical turbulence models under the default conditions can only reproduce the turbulent structure of the post-hill separation to a certain extent and that the nonlinear models (NBA1 and NBA2) simulate more hairpin vortices and small-scale vortex structures than the linear models (SMAG and TKE). Then, the parameter sensitivity is clarified by adjusting key parameters of four classical WRF-LES turbulence models. The results show that the ability of the linear models to simulate the separated flow and small-scale vortex structure is sensitive to the vortex viscosity coefficient. Once the nonlinear models are used, the simulation results are insensitive to the backscatter coefficient variation.

与传统的CFD模式相比，天气研究与预报模式（WRF）能更真实地再现台风等极端天气灾害下复杂的时空变化风场。然而，WRF（WRF-LES）预测工程尺度湍流的大涡模拟模式在不同的湍流模型方面还有待明确。本研究选择了一个三维山丘作为研究对象。我们以经过三维山丘的分离流为研究对象，系统地重新审视了四种湍流模型（SMAG、TKE、NBA1、NBA2）的影响。结果表明，在默认条件下，四种经典湍流模型只能在一定程度上再现山丘分离后的湍流结构，而非线性模型（NBA1 和 NBA2）比线性模型（SMAG 和 TKE）模拟了更多的发夹涡和小尺度涡旋结构。然后，通过调整四个经典 WRF-LES 湍流模型的关键参数，阐明了参数敏感性。结果表明，线性模型模拟分离流和小尺度涡旋结构的能力对涡旋粘度系数很敏感。使用非线性模型后，模拟结果对反向散射系数的变化不敏感。

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引用次数: 0

Fluid-structure interaction analysis of a 4:1 rectangular prism undergoing vortex-induced vibration 对发生涡流诱导振动的 4:1 矩形棱柱进行流固耦合分析

IF 4.2 2区工程技术 Q1 ENGINEERING, CIVIL

Journal of Wind Engineering and Industrial Aerodynamics

Pub Date : 2024-10-17 DOI: 10.1016/j.jweia.2024.105918

Zhanbiao Zhang, Fuyou Xu, Yuqi Wang, Xu Wang

The vortex-induced vibration (VIV) characteristics and fluid-structure interaction mechanism of a 4:1 rectangular prism is investigated in this study based on large-eddy simulations. Variations of the vibration amplitude, vortex-induced force, and surface pressure with the inflow velocity (U∗) are analyzed. Some significant questions regarding the VIV responses are raised and explained based on dynamic mode decomposition (DMD) and phase analyses of the flow fields. The cooperative shedding process of the motion-induced leading-edge vortex and the Karmon-type trailing-edge vortex that sustains the VIV is identified in the DMD mode. It is found that the phase difference between the leading and trailing-edge vortices in the near wake increases with U∗, leading to the eventual disappearance of VIV at a critical U∗. The root-mean-squared lift coefficient (C_L_rms) reaches its highest value in the initial phase of lock-in range, and then shows a monotonic reduction with increasing U∗. However, the structure could maintain a relatively large vibration amplitude until VIV disappears, even though the C_L_rms may be as low as that for the static case. This phenomenon is explained in detail based on the variations in phase distributions of the surface pressure with increasing U∗.

本研究基于大涡流模拟，研究了 4:1 矩形棱柱的涡致振动（VIV）特性和流固耦合机理。分析了振动振幅、涡诱力和表面压力随流入速度 (U∗) 的变化。根据流场的动模分解（DMD）和相位分析，提出并解释了有关 VIV 响应的一些重要问题。在 DMD 模式中，确定了运动诱导的前缘漩涡和维持 VIV 的 Karmon 型后缘漩涡的协同脱落过程。研究发现，近尾流中前缘漩涡和后缘漩涡的相位差随 U∗ 的增大而增大，最终导致 VIV 在临界 U∗ 时消失。均方根升力系数（CL_rms）在锁定范围的初始阶段达到最高值，然后随着 U∗ 的增大而单调降低。然而，尽管 CL_rms 可能与静态情况下一样低，结构仍可保持相对较大的振幅，直至 VIV 消失。这种现象的详细解释基于表面压力随 U∗ 增大而变化的相位分布。

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引用次数: 0

Effect and mechanism of stiffness distribution and sag-span ratio of main cables on structural dynamic characteristics and flutter performance of multi-cable suspension bridges 主缆刚度分布和矢跨比对多缆悬索桥结构动力特性和飘移性能的影响及机理

IF 4.2 2区工程技术 Q1 ENGINEERING, CIVIL

Journal of Wind Engineering and Industrial Aerodynamics

Pub Date : 2024-10-16 DOI: 10.1016/j.jweia.2024.105919

Yunliang Shi, Yongxin Yang, Jinbo Zhu, Jinjie Zhang

By incorporating extra load-carrying main cables, multi-cable suspension bridges provide increased flexibility in adjusting structural dynamic characteristics, and new possible solutions to the flutter instability problem of long-span bridges. Based on a multi-cable suspension bridge, this paper presents a particular insight into the dynamic characteristics which was contrast with double-cable suspension bridge. Furthermore, the influence of stiffness distribution and sag-span ratio of main cables on the dynamic characteristics was also studied. It is shown that due to the different contribution of the main cables, multi-cable suspension bridge has various torsional modes with similar vibration shapes of the stiffening girder, which is quite different from double-cable suspension bridge. Changes in stiffness distribution of main cables also have significant effects on the form of these torsional modes. On this basis, the flutter performance of multi-cable suspension bridge is studied by modality-driven method. The results indicate that the flutter critical wind speed increases with the increase of sag-span ratio and stiffness ratio of inner and outer main cables, and multi-cable suspension bridge can obtain better flutter performance than double-cable suspension bridge with appropriate stiffness distribution. The change of stiffness distribution and sag-span ratio may lead to the transition of flutter dominant mode.

通过加入额外的承载主缆，多缆悬索桥在调整结构动态特性方面提供了更大的灵活性，并为解决大跨度桥梁的飘移失稳问题提供了新的可能方案。本文以多索悬索桥为基础，对比双索悬索桥，对其动态特性进行了深入研究。此外，还研究了主缆刚度分布和矢跨比对动态特性的影响。结果表明，由于主缆的作用不同，多缆悬索桥具有各种扭转模式，加劲梁的振动形状相似，这与双缆悬索桥截然不同。主缆刚度分布的变化对这些扭转模态的形式也有显著影响。在此基础上，采用模态驱动法研究了多索悬索桥的扑动性能。结果表明，扑翼临界风速随内外主缆的矢跨比和刚度比的增大而增大，多索悬索桥比具有适当刚度分布的双索悬索桥能获得更好的扑翼性能。刚度分布和矢跨比的变化可能会导致扑翼主导模式的转变。

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引用次数: 0

Feasibility study of data-driven wall interference correction framework for subsonic wind tunnel 亚音速风洞数据驱动壁面干扰修正框架可行性研究

IF 4.2 2区工程技术 Q1 ENGINEERING, CIVIL

Journal of Wind Engineering and Industrial Aerodynamics

Pub Date : 2024-10-15 DOI: 10.1016/j.jweia.2024.105923

Myungsik Tai , Hyeonwoo Hwang , Shinkyu Jeong , Jongseo Bak , Donghun Park

Although the classical method is widely used for wall interference correction in wind tunnel testing, its reliability and accuracy for complex and unconventional geometries are rather limited. Studies on the evaluation of wall interference and the improvement of correction methods are desirable to enhance the reliability and generality for various geometric configurations. This study proposes a wall interference correction framework based on a deep neural network (DNN) ensemble using data obtained from the numerical panel method. The panel method is validated by comparing the results with those of Reynolds-averaged Navier-Stokes simulations. An automated process was established to generate a large amount of training data, and 600,000 datasets were generated based on the geometric parameters of the wind tunnel, test model, and angles of attack. The input variables of the DNN were determined through sensitivity analysis of the data. To alleviate the randomness of the initial weights and data distribution in the generation process of the DNN model, 20 DNNs with the same multi-layer perceptron structure were trained, and a DNN ensemble model was constructed using five ensemble members with high predictability. The accuracy of the DNN-ensemble based correction models were evaluated by comparing the correction results for the testing data.

虽然经典方法被广泛用于风洞试验中的壁面干扰校正，但其对于复杂和非常规几何结构的可靠性和准确性相当有限。为了提高各种几何构造的可靠性和通用性，有必要对壁面干扰的评估和修正方法的改进进行研究。本研究利用数值面板法获得的数据，提出了基于深度神经网络（DNN）集合的壁面干涉修正框架。通过将结果与雷诺平均纳维-斯托克斯模拟结果进行比较，验证了面板法。为生成大量训练数据建立了一个自动化流程，并根据风洞的几何参数、测试模型和攻角生成了 600,000 个数据集。DNN 的输入变量是通过对数据的敏感性分析确定的。为减轻 DNN 模型生成过程中初始权重和数据分布的随机性，训练了 20 个具有相同多层感知器结构的 DNN，并使用五个具有高预测性的集合成员构建了 DNN 集合模型。通过比较测试数据的修正结果，评估了基于 DNN 集合的修正模型的准确性。

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引用次数: 0

Numerical investigation on the impact of aerodynamic braking plates positioned at streamlined sections on the slipstream and wake flow of the high-speed train based on train-fixed reference frame 基于列车固定参照系的流线型区段空气动力制动板对高速列车滑流和尾流影响的数值研究

IF 4.2 2区工程技术 Q1 ENGINEERING, CIVIL

Journal of Wind Engineering and Industrial Aerodynamics

Pub Date : 2024-10-15 DOI: 10.1016/j.jweia.2024.105920

Puyang Zhang , Guangjun Gao , Jiabin Wang , Wenfei Shang , Liu Cao , Xinchao Su

This paper studies the aerodynamic characteristics of high-speed trains (HSTs) featuring aerodynamic braking plates installed on the streamlined sections, employing the improved delayed detached eddy simulation (IDDES) method at Re = 5.0 × 10⁵. The precision of the numerical simulation methodology has been validated through reduced-scale wind tunnel experiments. A comparative analysis has been conducted on the characteristics of slipstream, wake flow, and upper flow between the original configuration (OC) and the braking configuration (BC) of the HSTs. The findings reveal that the application of braking plates promotes significant separation phenomena around the HSTs, enhancing the slipstream velocity distribution. In the BC, compared to the OC, the maximum value of the time-averaged slipstream velocity has increased by approximately 134.9% and 76.8% at the trackside and platform positions, respectively. Additionally, the TSI value of the slipstream velocity shows increases of around 100.4% and 210.4% at the trackside and platform positions, respectively. Meanwhile, the turbulence fluctuations within the wake region have been enhanced, with the formation of a longitudinal vortex alongside the railway subgrade, whose core nearly covers the TSI positions. Notably, obvious shifts occur within the upper flow field, which significantly strengthens both flow turbulence and slipstream velocity, potentially influencing components on the upper surface of HSTs, such as the pantograph. The deployment of braking plates contributes to a significant increase in overall vehicle pressure drag, thereby enhancing the train's aerodynamic drag. Relative to the OC, the aerodynamic drag of the HST has increased by approximately 235.4% in the BC.

本文采用改进的延迟分离涡模拟（IDDES）方法，在 Re = 5.0 × 105 的条件下研究了高速列车（HST）的气动特性，该列车的流线型部分安装了气动制动板。通过缩小尺度的风洞实验验证了数值模拟方法的精确性。对 HST 原始配置（OC）和制动配置（BC）之间的滑流、尾流和上层流特性进行了对比分析。研究结果表明，制动板的应用促进了 HST 周围的显著分离现象，增强了滑流速度分布。在 BC 中，与 OC 相比，轨道边和平台位置的时间平均滑流速度最大值分别增加了约 134.9% 和 76.8%。此外，滑流速度的 TSI 值在轨道边和平台位置分别增加了约 100.4% 和 210.4%。同时，尾流区域内的湍流波动也增强了，在铁路路基旁形成了一个纵向涡流，其核心几乎覆盖了 TSI 位置。值得注意的是，上部流场发生了明显的变化，极大地增强了流动湍流和滑流速度，可能会影响 HST 上表面的部件，如受电弓。制动板的展开会显著增加整个车辆的压力阻力，从而增强列车的空气阻力。与正常运行时相比，在 BC 阶段 HST 的空气阻力增加了约 235.4%。

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引用次数: 0