Physics of Fluids最新文献_第10页

Gas physisorption impact on prolate dust in free-molecule flows: A static study 气体物理吸附对自由分子流中棱形尘埃的影响：静态研究

Physics of Fluids Pub Date : 2024-05-01 DOI: 10.1063/5.0207053

Hsin-Chen Yu, Xiaoping Zhang, Lei Wu, Zhongzhou Ren, Peishan He

{"title":"Gas physisorption impact on prolate dust in free-molecule flows: A static study","authors":"Hsin-Chen Yu, Xiaoping Zhang, Lei Wu, Zhongzhou Ren, Peishan He","doi":"10.1063/5.0207053","DOIUrl":"https://doi.org/10.1063/5.0207053","url":null,"abstract":"Gas–solid coupling systems operating at low pressure or the micro/nanoscale generally exist in nature and industrial manufacture. Although the gas-scattering model has been widely used to study this problem on the dust surface, the consideration of gas physisorption was often neglected in previous applications of gas–surface scattering models. Therefore, this study aims to investigate the distribution of gas physisorption on the dust surface and assess its impact on the static force experienced by nonspherical dust in free-molecule flows. In this study, the prolate dust spinning around its minor axis is considered and the in-house direct simulation Monte Carlo code is used. Results show that gas physisorption on prolate dust is influenced by changes in gas number densities, Mach number, and dust shape. Furthermore, the gas physisorption enhances the gas–dust coupling for dust with a smooth surface at low gas pressure, attributed to the increasing ratio of Maxwell diffuse scattering of gas molecules on the gas-adsorbed part of the surface. Hence, gas physisorption was suggested as a potential factor for gas–dust coupling at low gas pressure.","PeriodicalId":509470,"journal":{"name":"Physics of Fluids","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141028791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Identification of full-field wind loads on buildings using a mechanism-inspired recursive convolutional neural network with partial structural responses 利用部分结构响应的机制启发递归卷积神经网络识别建筑物的全场风荷载

Physics of Fluids Pub Date : 2024-05-01 DOI: 10.1063/5.0206423

Fubo Zhang, Ying Lei, Lijun Liu, Jinshan Huang

{"title":"Identification of full-field wind loads on buildings using a mechanism-inspired recursive convolutional neural network with partial structural responses","authors":"Fubo Zhang, Ying Lei, Lijun Liu, Jinshan Huang","doi":"10.1063/5.0206423","DOIUrl":"https://doi.org/10.1063/5.0206423","url":null,"abstract":"Indirect identification approaches through structural responses have proven effective for wind load estimation in real-world engineering. Currently, methods for identifying wind loads mainly rely on theoretical inverse identification, with rare research based on the mapping relationship between structural responses and wind loads through machine learning. In this paper, a scheme for identifying full-field wind loads using a recursive convolutional neural network (CNN) inspired by physical mechanisms is proposed. The recursive form of the network, as well as the inspiration for its inputs and outputs, is inspired by the spatial correlation and the mapping relationship between wind loads and structural responses. Thus, the network inputs comprise a fusion of structural acceleration and inter-story displacement responses, while the network outputs represent the independent wind loads on structures. Notably, mismatch test is employed by the network, wherein the training and testing datasets originate from entirely different sources. Specifically, during training, Gaussian white noises that simulate wind loads are utilized, while real wind load data are used for testing. The generalization of the proposed scheme is demonstrated through the identification of full-field wind loads generated by different stationary or non-stationary wind spectra of the 76-story wind-excited benchmark building. Furthermore, the proposed scheme is validated by identifying the full-field wind loads of a 67-story shear wall structure with wind tunnel test data.","PeriodicalId":509470,"journal":{"name":"Physics of Fluids","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141035987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Falling film hydrodynamics and heat transfer under vapor shearing from various orientations 不同方向蒸汽剪切作用下的落膜流体力学和热传导

Physics of Fluids Pub Date : 2024-05-01 DOI: 10.1063/5.0210075

Chuang-Yao Zhao, Qiong Li, Fang-Fang Zhang, Di Qi, Hasan Yildizhan, Jun-Min Jiang

{"title":"Falling film hydrodynamics and heat transfer under vapor shearing from various orientations","authors":"Chuang-Yao Zhao, Qiong Li, Fang-Fang Zhang, Di Qi, Hasan Yildizhan, Jun-Min Jiang","doi":"10.1063/5.0210075","DOIUrl":"https://doi.org/10.1063/5.0210075","url":null,"abstract":"Vapor shearing is a common issue encountered in the operations of falling film heat exchangers. The vapor stream effect depends on its orientation. This study investigates liquid film hydrodynamics and heat transfer performance under the influence of vapor streams from different orientations. The results indicate that both orientation and velocity of vapor determine the encountering time and position of the films on the tube's two sides. The liquid film thickness uniformity and the liquid column deflection vary significantly depending on the orientation and velocity of the vapor. Zones of accelerated liquid film, climbing liquid film, liquid stagnation, and transition of liquid film flow pattern are observed. The gradient of film thickness along the tube axis and the deflection in time-averaged peripheral film thickness increase as the vapor orientation varies from 0° to 90° and subsequently decrease as the vapor orientation varies from 90° to 180°. Vapor streams have more pronounced effects on time-averaged peripheral film thickness in regions close to the liquid inlet and outlet. Vapor streams result in changes in peripheral heat transfer coefficients toward the downstream side depending on the orientation and velocity of the vapor. The impact of vapor streams on the overall heat transfer coefficient does not directly correlate with the velocity of the vapor when maintaining the same orientation.","PeriodicalId":509470,"journal":{"name":"Physics of Fluids","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141039799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A wall-modeled immersed boundary/large eddy simulation method and its application to simulating heart valve flows 壁模型沉浸边界/大涡流模拟方法及其在模拟心脏瓣膜流动中的应用

Physics of Fluids Pub Date : 2024-05-01 DOI: 10.1063/5.0198734

Jingyang Wang, T. Pu, Chunhua Zhou

{"title":"A wall-modeled immersed boundary/large eddy simulation method and its application to simulating heart valve flows","authors":"Jingyang Wang, T. Pu, Chunhua Zhou","doi":"10.1063/5.0198734","DOIUrl":"https://doi.org/10.1063/5.0198734","url":null,"abstract":"In this work, a wall-modeled immersed boundary (IB)/large eddy simulation (LES) method is extended to the simulation of moving-boundary flows. The used non-equilibrium algebraic wall model is based on an assumed velocity profile, the coefficients of which are determined from physical constraints provided by the full turbulent-boundary-layer equations. To implement the wall model in an IB method named the local domain-free discretization (DFD) method, a local coordinate system fixed on the moving body is introduced. Thus, wall modeling is transformed into a local two-dimensional problem and the complexity of implementation of the wall model is reduced. In the present LES-DFD method, the tangential velocity at an exterior dependent node is determined via wall shear stress prescribed by the wall model. To reduce computational cost for simulating an internal flow with moving boundaries, the stationary boundaries are handled by the body-fitted-grid method and the moving boundaries by the local DFD method. There is no need of an auxiliary grid for solving the non-equilibrium algebraic wall model. Therefore, the inbuilt advantage of an IB method can be retained when simulating moving-boundary problems, and the economy of equilibrium wall models can also be preserved. The present method is applied to simulating the pulsatile flows through a bileaflet mechanical heart valve implanted in a model aorta. The predicted results show an acceptable agreement with the referenced experimental measurements or numerical results at much higher resolution and the applicability of the non-equilibrium wall model to LES of complex moving-boundary flows is verified.","PeriodicalId":509470,"journal":{"name":"Physics of Fluids","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141030910","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of compressibility on Richtmyer–Meshkov instability of heavy/light interface 压缩性对重质/轻质界面里氏不稳定性的影响

Physics of Fluids Pub Date : 2024-05-01 DOI: 10.1063/5.0207779

Jiaxuan Li, Chenren Chen, Z. Zhai, Xisheng Luo

{"title":"Effects of compressibility on Richtmyer–Meshkov instability of heavy/light interface","authors":"Jiaxuan Li, Chenren Chen, Z. Zhai, Xisheng Luo","doi":"10.1063/5.0207779","DOIUrl":"https://doi.org/10.1063/5.0207779","url":null,"abstract":"Experimental and numerical studies on the evolution of shock-accelerated SF6/air interface with small initial amplitude are conducted. The effect of compressibility on the early development of perturbation is highlighted by varying shock intensity and fluid properties. The startup process is analyzed when rarefaction waves are reflected and the characteristic time of the startup process is provided. The relationship between the phase inversion process and the startup process under different incident shock strengths is clarified. According to the startup time, a new start point for normalization is given, which can better normalize the amplitude growth at the early stage. In addition, the effects of incident shock strength and physical properties of fluids on the linear growth rate are highlighted through numerical simulations. The incompressible linear model loses validity when the incident shock is strong, and the existing rotational model is verified to provide excellent predictions under any shock strengths. The decrease in adiabatic exponent of the heavy fluid or the increase in adiabatic exponent of the light fluid can reduce the linear growth rate. As the absolute value of Atwood number increases, the adiabatic exponent of the heavy fluid has a more significant effect on the linear growth than that of the light fluid.","PeriodicalId":509470,"journal":{"name":"Physics of Fluids","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141046946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Data-driven learning algorithm to predict full-field aerodynamics of large structures subject to crosswinds 预测受横风影响的大型结构全场空气动力学的数据驱动学习算法

Physics of Fluids Pub Date : 2024-05-01 DOI: 10.1063/5.0197178

Xianjia Chen, Bo Yin, Zheng Yuan, Guowei Yang, Qiang Li, Shouguang Sun, Yujie Wei

{"title":"Data-driven learning algorithm to predict full-field aerodynamics of large structures subject to crosswinds","authors":"Xianjia Chen, Bo Yin, Zheng Yuan, Guowei Yang, Qiang Li, Shouguang Sun, Yujie Wei","doi":"10.1063/5.0197178","DOIUrl":"https://doi.org/10.1063/5.0197178","url":null,"abstract":"Quick and high-fidelity updates about aerodynamic loads of large-scale structures, from trains, planes, and automobiles to many civil infrastructures, serving under the influence of a broad range of crosswinds are of practical significance for their design and in-use safety assessment. Herein, we demonstrate that data-driven machine learning (ML) modeling, in combination with conventional computational methods, can fulfill the goal of fast yet faithful aerodynamic prediction for moving objects subject to crosswinds. Taking a full-scale high-speed train, we illustrate that our data-driven model, trained with a small amount of data from simulations, can readily predict with high fidelity pressure and viscous stress distributions on the train surface in a wide span of operating speed and crosswind velocity. By exploring the dependence of aerodynamic coefficients on yaw angles from ML-based predictions, a rapid update of aerodynamic forces is realized, which can be effectively generalized to trains operating at higher speed levels and subject to harsher crosswinds. The method introduced here paves the way for high-fidelity yet efficient predictions to capture the aerodynamics of engineering structures and facilitates their safety assessment with enormous economic and social significance.","PeriodicalId":509470,"journal":{"name":"Physics of Fluids","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141049096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of surface slip on hydrodynamics and flow field around a two-dimensional hydrofoil at a moderate Reynolds number 表面滑移对中等雷诺数下二维水翼周围流体力学和流场的影响

Physics of Fluids Pub Date : 2024-05-01 DOI: 10.1063/5.0203389

Manfu Zhu, Weixi Huang, Liran Ma, Jianbin Luo

{"title":"Influence of surface slip on hydrodynamics and flow field around a two-dimensional hydrofoil at a moderate Reynolds number","authors":"Manfu Zhu, Weixi Huang, Liran Ma, Jianbin Luo","doi":"10.1063/5.0203389","DOIUrl":"https://doi.org/10.1063/5.0203389","url":null,"abstract":"In the present study, the effects of surface slip on the hydrodynamics and flow around a two-dimensional National Advisory Committee for Aeronautics 0012 hydrofoil are systematically investigated by numerical methods. The objective is to fully understand the effects of surface slip on the streamlined body. Three slip positions (both surfaces, the upper surface, the lower surface) and eight slip lengths (in a wide range from 1 to 500 μm) under 0°–10° angles of attack are fully investigated at a moderate Reynolds number of 1.0 × 106. Surface slip has been found to increase lift and reduce drag by postponing the flow transition, laminar separation bubble, and flow separation on the hydrofoil surface under both surfaces and the upper surface slip conditions. Slip has also been found to induce upshift of the mean velocity profile, decrease the displacement thickness, and mitigate the turbulent kinetic energy in the flow field. However, counterintuitive phenomenon occurs under the lower surface slip condition, where the total drag of the hydrofoil is increased compared to that under the no slip condition. Total drag increase is found mainly due to the increase in the pressure drag under small slip lengths and relatively large angles of attack. Flow maps demonstrating the complex interaction between different surface slip conditions and the flow field are further presented. The results suggest that surface slip can not only reduce drag, but also increase the drag of the streamlined body, which shall provide valuable insights for practical applications of slippery materials.","PeriodicalId":509470,"journal":{"name":"Physics of Fluids","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141045462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electrohydrodynamic deformation of a compound droplet in an alternating current and direct current superposed electric field 复合液滴在交流和直流叠加电场中的电流体动力变形

Physics of Fluids Pub Date : 2024-05-01 DOI: 10.1063/5.0209008

Bikash Mohanty, Aditya Bandopadhyay

{"title":"Electrohydrodynamic deformation of a compound droplet in an alternating current and direct current superposed electric field","authors":"Bikash Mohanty, Aditya Bandopadhyay","doi":"10.1063/5.0209008","DOIUrl":"https://doi.org/10.1063/5.0209008","url":null,"abstract":"In this study of a compound droplet subjected to alternating current (AC) and direct current (DC) superposed (AC/DC) electric fields, both core and shell deformations oscillate, albeit with reduced amplitude compared to solely alternating current electric fields. As surface tension relaxes, periodic cyclic deformation ensues, with mean deformation amplifying alongside electric field amplitude. Concurrently, normal and tangential Maxwell stresses escalate with amplitude, thus augmenting interfacial surface velocities. Manipulating the offset ratio of alternating and direct current superposed electric field modulates mean deformations. Across low frequencies, stable deformation remains constant, yet a delayed onset characterizes higher frequencies. The presence of a core affects the electrohydrodynamics of the compound droplet and shell deformation, thereby mitigating phase differences between cyclic deformations. Contrasting alternating current (AC)—only fields, alternating current and direct current superposed (AC/DC) electric field scenarios exhibit heightened surface charge densities and prompter stable deformation onset. Furthermore, the direct current component magnifies mean deformations while harmonizing phase disparities between core and shell deformations. This study illuminates the intricate interplay between alternating current and direct current fields on compound droplet behavior, offering profound insight with broad implications for applications necessitating precise deformations under electric fields.","PeriodicalId":509470,"journal":{"name":"Physics of Fluids","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141037891","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Free surface water waves generated by instability of an exponential shear flow in arbitrary depth 任意深度指数剪切流不稳定性产生的自由水面波浪

Physics of Fluids Pub Date : 2024-05-01 DOI: 10.1063/5.0208081

M. Abid, C. Kharif

{"title":"Free surface water waves generated by instability of an exponential shear flow in arbitrary depth","authors":"M. Abid, C. Kharif","doi":"10.1063/5.0208081","DOIUrl":"https://doi.org/10.1063/5.0208081","url":null,"abstract":"The stability of an exponential current in water to infinitesimal perturbations in the presence of gravity and capillarity is revisited and reformulated using the Weber and Froude numbers. Some new results on the generation of gravity-capillary waves are presented, which supplement the previous works of Morland et al. [“Waves generated by shear layer instabilities,” Proc. Math. Phys. Sci. 433, 441–450 (1991)] and Young and Wolfe [“Generation of surface waves by shear-flow instability,” J. Fluid Mech. 739, 276–307 (2014)] on finite depth. To consider perturbations at much larger scales, special attention is given to the stability of exponential currents only in the presence of gravity. More precisely, the present investigation reveals significant insights into the stability of exponential shear currents under different environmental conditions. Notably, we have identified that the dimensionless growth rate increases with the Froude number, providing a deeper understanding of the interplay between shear layer thickness and surface velocity. Furthermore, our analysis elucidates the dimensional wavelength of the most unstable mode, emphasizing its relevance to the characteristic shear layer thickness. Additionally, within the realm of gravity-capillary instabilities, we have established a sufficient condition for the stability of exponential currents based on the Weber number. Our findings are supported by stability diagrams at finite depth, showing how the size of stable domains correlates with the characteristic thickness of the shear layer. Moreover, we have explored the stability of a thin film of liquid in an exponential shearing flow, further enriching our understanding of the complex dynamics involved in such systems.","PeriodicalId":509470,"journal":{"name":"Physics of Fluids","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141051165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Pressure characteristics of a nonspherical underwater explosion bubble in a compressible fluid 非球形水下爆炸气泡在可压缩流体中的压力特性

Physics of Fluids Pub Date : 2024-05-01 DOI: 10.1063/5.0206482

Junliang Liu, Wei Xiao, Xiongliang Yao

{"title":"Pressure characteristics of a nonspherical underwater explosion bubble in a compressible fluid","authors":"Junliang Liu, Wei Xiao, Xiongliang Yao","doi":"10.1063/5.0206482","DOIUrl":"https://doi.org/10.1063/5.0206482","url":null,"abstract":"The pressures produced by underwater explosions present serious threats to ships, submarines, and other marine structures. A significant part of underwater explosion pressure comes from the explosion bubble. Most computational studies on bubble pressure have considered the case of an incompressible fluid or have confined calculations to the time before the formation of a toroidal bubble, because of the complexity and strong nonlinearity of a compressible flow field with a doubly connected geometry. The few compressible models that are capable of calculating the pressure after jet impact suffer from computational difficulties. In this paper, we calculate the bubble pressure by constructing a new form for solving an auxiliary function based on a boundary integral method that takes account of the compressibility of the flow field. We verify out numerical algorithm by comparison with a classical theoretical model and a set of experimental results. We then compare the bubble pressure in a compressible flow field in both the first and second oscillation periods with that in an incompressible flow field. The results of this comparison confirm that it is necessary to consider the compressibility of the fluid and the multiperiod pulsations of a bubble in pressure calculations. We present a comprehensive discussion of the pressure characteristics in the central axial and circumferential directions induced by a nonspherical bubble in a free field. Finally, we obtain a critical bubble–wall distance rw > 1.8 for which the bubble is prevented from splitting after the first jet impact, and we investigate the pressure characteristics of a bubble near a rigid wall for both cases of rw < 1.8 and rw > 1.8.","PeriodicalId":509470,"journal":{"name":"Physics of Fluids","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141132624","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0