Numerical Study of a Supersonic Nozzle Gas Jet Laden with a Dry Powder Fire-extinguishing Agent Injected from a Bypass Injector by L. Zhang, S. Wu, Y. Feng, H. Guan

“…During the simulation, we employed our newly developed modified drag coefficient model, capable of accommodating a broad spectrum of particle Reynolds and Mach number conditions. …”
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The Determination of Satellite Orbital Decay From POD Data During Geomagnetic Storms by Ruoxi Li, Jiuhou Lei

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Improving Thermospheric Density Predictions in Low‐Earth Orbit With Machine Learning by Giacomo Acciarini, Edward Brown, Tom Berger, Madhulika Guhathakurta, James Parr, Christopher Bridges, Atılım Güneş Baydin

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Experimental investigation into flow resistance of large benthic crab burrows in the Yellow River Delta, China by Wenbo Zhu, Yan Lu, Chengyang Zhou, Yongjun Lu, Pan Wu, Liqin Zuo, Tingjie Huang, Huaiqian Xiao

“…The experimental results show that there is a significant positive correlation between the drag coefficient, and the hydraulic radius, and cave density, and a negative correlation with the Reynolds number, and the modification for the sidewall and bed effect greatly improves the representativeness of the measured data. …”
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Realtime Precise Orbit Determination Technology for LEO Mega-Constellation by Zhen LI, Chuang SHI

“…Supported by GNSS, it analyzed the advantages and disadvantages of solving LEO satellite orbit on the ground or onboard the satellites.The high-fidelity non-conservative force models were applied to the real-time orbit determination algorithm.To separate the kinematic and dynamic orbit determination process had been a great advantage for LEO satellites with much frequent orbital maneuvers.The test results showed that the accuracy of accelerations computed from the radiation pressure and atmospheric drag non-conservation force models were around 5 nm/s².Use the broadcast ephemeris, the real-time orbit determination algorithm could get an accuracy of 0.8 m in the satellites′ positions and 1.1 mm/s accuracy in the satellites′ velocity.When the real-time precise ephemeris of GNSS satellites were provided, the algorithm could get an accuracy of 8 cm in the LEO satellites′ position and 0.1 mm/s in the velocity.The method for real-time orbit determination and orbit prediction in this paper could be used to support the construction of navigation system with the mega-constellations.…”
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Heavy metal concentrations in fishes from Zakrzówek Reservoir and the Vistula River near Kraków: Human risk assessment by Łuszczek-Trojnar Ewa, Drąg-Kozak Ewa, Szczerbik Paweł, Klaczak Artur, Lelonek Anna, Duda Kinga, Adamska Patrycja

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Effect of V-Shaped Groove Microstructure on Blood Flow Resistance in Bionic Artificial Blood Vessels by Zhou Li, Yunqing Gu, Lingzhi Yu, Zhuofan Yin, Wenting Wang, Denghao Wu, Jiegang Mou, Shuihua Zheng

“…This study aims to investigate the blood flow in bionic artificial blood vessels and to reduce the resistance to blood flow, the drag reduction characteristics of V-shaped groove drag reduction microstructures in artificial blood vessel structures were investigated in depth. …”
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Numerical and experimental investigation of the steering performance of a ringsail parachute by HUANG Yunyao, WU Shiqing, WANG Yongbin, ZHANG Yang

“…Comparison between the results obtained by the wind tunnel test and numerical simulation shows that the trend of drag coefficient and drag characteristic curves are basically consistent, and the relative error between them is within 20%, indicating the reliability of the numerical method.…”
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A New Aerodynamic Optimization Method with the Consideration of Dynamic Stability by Mi Baigang, Wang Xiangyu

“…We take NACA0012 as an example to validate this method. The results show that the dynamic derivative calculation method is effective and conventional optimization design can significantly improve the lift-drag ratio. …”
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Lift Enhancement of Tiltrotor Wing Using a Gurney Flap by Hao Chen, Bo Chen

“…On the other hand, the Gurney flap also results in a drag penalty, and the overall effect on the wing lift-to-drag is detrimental. …”
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Shape Optimization of NREL S809 Airfoil for Wind Turbine Blades Using a Multiobjective Genetic Algorithm by Yilei He, Ramesh K. Agarwal

“…The commercially available software FLUENT is employed to calculate the flow field on an adaptive structured mesh using the Reynolds-Averaged Navier-Stokes (RANS) equations in conjunction with a two-equation k-ω SST turbulence model. The results show significant improvement in both lift coefficient and lift to drag ratio of the optimized airfoil compared to the original S809 airfoil. …”
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Effect of Gurney Flap Geometry on a S809 Airfoil by Li-Shu Hao, Yong-Wei Gao

“…By comparing with experimental data, such as the lift force, the drag coefficient, and the pressure distribution, the accuracy of the simulation method is validated. …”
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Accuracy Improvement Capability of Advanced Projectile Based on Course Correction Fuze Concept by Ahmed Elsaadany, Yi Wen-jun

“…The drag ring brake is found to be highly capable for range correction. …”
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Comparative analysis and manufacturing of airfoil structures suitable for use at low speeds by Sinan Fidan, Satılmış Ürgün, Mert Gökdemir

“…An aerodynamic technique to calculating lift and drag coefficients is one of the required instruments in the wing design process. …”
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Aerodynamic Investigation for a Propeller-Induced Lift-Enhancing Vertical Take-Off and Landing (VTOL) Configuration by Hongbo Wang, Guangjia Li, Jie Li, Junjie Zhuang

“…Numerical simulation methods are used to study and analyze the aerodynamic characteristics of this configuration in the cruise and VTOL phases. The results show that the favorable inducing effect of the propeller makes the PILE configuration have a good effect of increasing lift and reducing drag compared with a single wing of the same area during the cruise phase, improving the lift-to-drag ratio by 7.27%. …”
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Spectral Element Numerical Investigation of Flow between Three Cylinders in an Equilateral-Triangular Arrangement with Different Spacing Distances by Zhenzhong Bao, Guoliang Qin, Wenqiang He, Yazhou Wang

“…Mean drag coefficients of downstream cylinders are basically identical to the value of flow past around a single circular cylinder. …”
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Influence of Spiral Angle on the Performance of Spiral Oil Wedge Sleeve Bearing by Li-li Wang, Qing-liang Zeng, Xin Zhang

“…Using the concept of partial derivatives, stiffness and damping coefficients of sleeve bearing are calculated. The results show that carrying capacity and friction drag of oil film decrease, temperature rise decreases first and then increases, and end leakage rate, stiffness, and damping coefficients generally increase first and then decrease with the increase of spiral angle. …”
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The Sub 2-h Official Marathon is Possible: Developing a Drafting Strategy for a Historic Breakthrough in Sports by G. D. Fernandes, Nazir Laureano Gandur, Dioser Santos, Victor Maldonado

“…Abstract Background Drafting for drag reduction is a tactic commonly employed by elite athletes of various sports. …”
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STUDY ON FLOW CHARACTERISTICS OF WAVE-SHAPED RODS WITH SPATIAL ANGLE OF ATTACK by ZHAO Meng, LIU MeiYing, JIA Yan, LIU XiaoYu, WANG YiHe

“…The velocity and pressure distribution laws of wave members with different wavelengths were investigated,and characteristics about time-domain and frequency-domain of the circumferential pressure coefficient,drag and lift were discussed. The results show that the larger the surface inclination,the higher the surface pressure variation. …”
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Experimental Investigation of a Wing-in-Ground Effect Craft by M. Mobassher Tofa, Adi Maimun, Yasser M. Ahmed, Saeed Jamei, Agoes Priyanto, Rahimuddin

“…The ground effect and the existence of the endplates increase the wing lift-to-drag ratio at low ground clearance. The results of this research work show new proposed design of the WIG craft with compound wing and endplates, which can clearly increase the aerodynamic efficiency without compromising the longitudinal stability. …”
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