NUMERICAL SIMULATION ANALYSIS AND THE DRAG REDUCTION PERFORMANCE INVESTIGATION ON CIRCULAR CYLINDER WITH DIMPLES AT SUBCRITICAL REYNOLDS NUMBER by WANG GuoRong, LIAO ChongJi, HU Gang, ZHONG Lin, ZHANG Min

“…The results show that the circular cylinder with dimples has a good effect on drag reduction. …”
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STUDY ON THE THERMAL-MECHANICAL COUPLING CHARACTERISTICS OF DISC BRAKE UNDER DRAG AND START-STOP BREAKING MODES by YUAN Qiong, LI ShiSheng

“…Results show that: under the effect of thermal-mechanical coupling,the thermal deformation forms of the brake pad on both sides of the disc are completely different,resulting in significant differences in the temperature distribution of the friction discs on both sides. …”
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Investigation into Shock Control and Drag Reduction Characteristics of Opposing Plasma Synthetic Jet in Mach 8 Flow by Xudong Zhang, Hao Dong, Xingyu Cao, Yan Zhou, Wei Xie, Wei Song, Yan Wang

“…The results show that an increase in discharge energy is beneficial for the drag reduction characteristics of the opposing PSJ, although the efficiency remains relatively low. …”
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Modeling the hydraulic roughness of a movable flatbed in a sand channel while considering the effects of water temperature by Junzheng Liu, Jinliang Zhang, Zhe Huang, Haijue Xu, Yuchuan Bai, Gang Wang

“…The new predictor suggested that the additional drag is nonlinearly proportional to the grain drag, and the scale factor between these two parameters is related to five flow‒sediment variables. …”
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Numerical Simulation Analysis and Research on Drag Reduction and Stability Enhancement Effect of Head Swing Based on Biomimetic Flexible Variants by Debo Qi, Yang Li, Baisheng Yang, Zhengyang Wu, Bo Li, Shichao Niu

“…The oscillation process was numerically simulated using Fluent software. The results show that, when the vehicle maintains a stationary posture, biasing the vehicle’s head towards the incoming flow direction can effectively reduce the radial drag and drag moment, thereby improving the stability of the vehicle. …”
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The Thermosphere Is a Drag: The 2022 Starlink Incident and the Threat of Geomagnetic Storms to Low Earth Orbit Space Operations by T. E. Berger, M. Dominique, G. Lucas, M. Pilinski, V. Ray, R. Sewell, E. K. Sutton, J. P. Thayer, E. Thiemann

“…We model the orbital altitude and in‐track position of a Starlink‐like satellite in a low‐drag configuration at 200 km during minor (G1) and extreme (G5) geomagnetic storms to show that an extreme storm would have at least a factor of two higher impact, with cumulative in‐track errors on the order of 10,000 km after a 5‐day duration extreme storm. …”
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Layout Optimization of Two Autonomous Underwater Vehicles for Drag Reduction with a Combined CFD and Neural Network Method by Wenlong Tian, Zhaoyong Mao, Fuliang Zhao, Zhicao Zhao

“…The optimization results show that (1) the total drag of the AUV fleet can be reduced by 12% when the follower AUV is located directly behind the leader AUV and (2) the drag of the follower AUV can be reduced by 66% when it is by the side of the leader AUV.…”
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Performance Analysis of Grid Topologies and RANS Turbulence Models in Predicting Aerodynamic Drag Coefficient at Zero-yaw for an Artillery Projectile by A. Ferfouri, D. D. Jerković, N. Hristov, A. V. Kari, T. Allouche

“…In terms of drag component results, both turbulence models and grid topologies performed equally in predicting pressure and friction drag, with differences less than 6% in all Mach number cases. …”
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Experimental and analytical investigation of hydraulic conductivity, energy dissipation, and drag forces in gradually varied flow conditions through rockfill media by Jafar Chabokpour

“…This paper focuses on the flow of water through rockfill porous media and brings out the effect of various parameters on hydraulic conductivity, friction factors, energy losses, drag coefficients, drag forces, and shear forces for such systems. …”
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Les Transparences by Lorraine Alexandre

“…This text presents my series of performative photographs called Les Transparences (“Transparencies”), 2007. By staging drag queens models, this series brings face-to-face the biological nature of sex and the performative nature of genders. …”
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Thermal Variability in the Martian Upper Atmosphere within the Crustal Magnetic Field Region Induced by Gravity Wave Dissipation Due to Ion-drag Effect by Xing Wang, Xiaojun Xu, Jun Cui, Siqi Yi, Hao Gu, Zilu Zhou, Hengyan Man, Lei Luo, Peishan He, Pu Yang

“…Our results show that the ion-drag effect influences wave propagation primarily above 160 km in the CF region and around 200 km in the noncrustal magnetic field (NCF) region. …”
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Global Variations in the Time Delays Between Polar Ionospheric Heating and the Neutral Density Response by Daniel R. Weimer, Piyush M. Mehta, R. J. Licata, W. K. Tobiska

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Comparison of a Neutral Density Model With the SET HASDM Density Database by Daniel R. Weimer, W. Kent Tobiska, Piyush M. Mehta, R. J. Licata, Douglas P. Drob, Jean Yoshii

“…These sums were compared as a function of time. The results show an excellent agreement at temporal scales ranging from hours to years. …”
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Experimental Simulation of a Tennis Ball using Wind Tunnel by Cesar Almiro de Souza, Julio Cesar Costa Campos, Antonio Marcos de Oliveira Siqueira, Pedro Casanova Treto, Alvaro Messias Bigonha Tibiriça, Henrique Márcio Pereira Rosa, Rogério Fernandes Brito

“…It was possible to analyze the effect of drag on the diameter, in the investigation of the relationship between the drag coefficient (CD) and the Reynolds number (Re) for new and used balls. …”
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Arm Propulsion in Front Crawl Stroke by Cristian Romagnoli, Vincenzo Bonaiuto, Giorgio Gatta

“…<b>Objectives</b>: This study aims to determine the propulsive force and effective arm area contributed by the propulsion through the dynamic balance (power balance) between drag and propulsive power in swimming crawl performance. …”
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Unveiling the Space Weather During the Starlink Satellites Destruction Event on 4 February 2022 by Tong Dang, Xiaolei Li, Bingxian Luo, Ruoxi Li, Binzheng Zhang, Kevin Pham, Dexin Ren, Xuetao Chen, Jiuhou Lei, Yuming Wang

“…Model simulations driven by solar wind show that the first geomagnetic storm induced around 20% atmospheric density perturbations at 210 km altitude on 3rd February. …”
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Thermospheric Temperature and Density Variability During 3–4 February 2022 Minor Geomagnetic Storm by F. I. Laskar, E. K. Sutton, D. Lin, K. R. Greer, S. Aryal, X. Cai, N. M. Pedatella, R. W. Eastes, W. Wang, M. V. Codrescu, W. E. McClintock

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Multi-objective Optimization Design of Wet Friction Clutches by Jiang Kai, Li Hua, Chen Si, Li Shilei, Ren Rongzhi

“…The drag torque of the wet clutch affects the efficiency of the transmission, and the engagement torque of the clutch affects the reliability of the transmission. …”
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The Effect of Surface Roughness of a Body in the High Reynolds-Number Flow by Tsutomu adachi

“…Then the surface conditions of a body have great effect on the flow phenomena and on the drag of the body. Some attempts to reduce the drag of the body were shown.…”
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Passive flow control devices for road vehicles: A comprehensive review by Md. Nazmus Salehin, Nayem Zaman Saimoon, Mim Mashrur Ahmed, Md. Rabiul Islam Sarker, Mahadi Hasan Masud

“…Firstly, the working physics behind different strategies, like deflectors, diffusers, spoilers, vortex generators, and flaps were elaborately discussed, followed by a detailed comparison among these techniques in terms of resultant drag and lift forces. Among several strategies, the gurney flap showed the huge potential of reducing 67.74% drag force with a slight increase in the lift force. …”
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