Deep reinforcement learning for turbulent drag reduction in channel flows. [PDF]
Eur Phys J E Soft Matter, 2023 We introduce a reinforcement learning (RL) environment to design and benchmark control strategies aimed at reducing drag in turbulent fluid flows enclosed in a channel.
Guastoni L +4 more
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Research Progress of Air Lubrication Drag Reduction Technology for Ships
Fluids, 2022 Air lubrication is a promising drag reduction technology for ships because it is considered to reduce the skin-friction resistance of ships by changing the energy of turbulent boundary layers.
Hai An, Haozhe Pan, Po Yang
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An energy-efficient pathway to turbulent drag reduction. [PDF]
Nat Commun, 2021 Simulations and experiments at low Reynolds numbers have suggested that skin-friction drag generated by turbulent fluid flow over a surface can be decreased by oscillatory motion in the surface, with the amount of drag reduction predicted to decline with
Marusic I +7 more
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Fabrication of Salvinia-inspired surfaces for hydrodynamic drag reduction by capillary-force-induced clustering. [PDF]
Nat Commun, 2022 For decades, bioinspired functional materials have been attracting the interest of many researchers for their remarkable characteristics. In particular, some plant leaves are well known for their inherent superhydrophobic nature. Salvinia molesta, a free-
Kim M, Yoo S, Jeong HE, Kwak MK.
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A Review of Recent Advances in Superhydrophobic Surfaces and Their Applications in Drag Reduction and Heat Transfer. [PDF]
Nanomaterials (Basel), 2021 Inspired by the superhydrophobic properties of some plants and animals with special structures, such as self-cleaning, water repellent, and drag reduction, the research on the basic theory and practical applications of superhydrophobic surfaces is ...
Zhang Y +4 more
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Active Control for Wall Drag Reduction: Methods, Mechanisms and Performance
IEEE Access, 2020 Active reducing the skin friction drag of vehicles (such as missiles, rockets, aircraft, high-speed train, submarines, etc.) during the navigation process can improve the respond speed effectively, save the energy consumption and increase the endurance ...
Lu Zhang, Xiaobiao Shan, Tao Xie
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Drag reduction by compressible bubbles [PDF]
Physical Review E, 2006 Drag reduction by bubbles in stationary turbulent flows is sensitive to the compressibility of the bubbles. Without this dynamical effect the bubbles only renormalize the fluid density and viscosity, an effect that by itself can only lead to a small percentage of drag reduction. We show in this paper that the dynamics of bubbles and their effect on the
T S, Lo +2 more
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A novel aerodynamic drag-reduction mechanism using dolphin-inspired ultrasonic microvibrations [PDF]
Scientific ReportsAerodynamic drag, particularly viscous drag, is a significant source of energy loss in aircraft, with its reduction being critical for improving overall aerodynamic performance.
Dongyue Wang, Hao Liu
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Synthesis and drag reduction properties of a hydrophobically associative polymer containing ultra-long side chains [PDF]
BMC Chemistry, 2023 Different from common hydrophobic associative polymers, a new hydrophobic associative polyacrylamide (HAPAM) with ultra-long side chains was synthesized and aimed to be used as drag reducer in this work.
Xianwu Jing +3 more
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Drag reduction by polymer additives from turbulent spectra [PDF]
, 2010 We extend the analysis of the friction factor for turbulent pipe flow reported by G. Gioia, P. Chakraborty and N. Goldenfeld (GCG) (G. Gioia and P. Chakraborty, Phys. Rev. Lett. 96, 044502 (2006), N. Goldenfeld, Phys. Rev. Lett. 96, 044503 (2006)) to the
Calzetta, Esteban
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