Results 31 to 40 of about 265,857 (305)
Drag Reduction by Leidenfrost Vapor Layers [PDF]
Physical Review Letters, 2011 We demonstrate and quantify a highly effective drag reduction technique that exploits the Leidenfrost effect to create a continuous and robust lubricating vapor layer on the surface of a heated solid sphere moving in a liquid. Using high-speed video, we show that such vapor layers can reduce the hydrodynamic drag by over 85%.
Vakarelski, Ivan Uriev +3 more
openaire +3 more sources
Exceeding the asymptotic limit of polymer drag reduction [PDF]
, 2017 The drag of turbulent flows can be drastically decreased by addition of small amounts of high molecular weight polymers. While drag reduction initially increases with polymer concentration, it eventually saturates to what is known as the maximum drag ...
Choueiri, George H. +2 more
core +3 more sources
Study on Aerodynamic Drag Reduction at Tail of 400 km/h EMU with Air Suction-Blowing Combination
Machines, 2023 In order to further reduce the aerodynamic drag of High-speed Electric Multiple Units (EMU), an active flow control drag reduction method combining air suction and blowing is proposed at the rear of the EMU train.
Hongjiang Cui +3 more
doaj +1 more source
Impact of the Microstructure of Polymer Drag Reducer on Slick-Water Fracturing
Geofluids, 2017 Many studies have focused on the drag reduction performance of slick-water, but the microdrag reduction mechanism remains unclear since the microstructure of the drag reducer and its effect on this mechanism have not been well studied. In this study, the
Zhi-yu Liu +5 more
doaj +1 more source
Bubbly Turbulent Drag Reduction Is a Boundary Layer Effect [PDF]
, 2007 In turbulent Taylor-Couette flow, the injection of bubbles reduces the overall drag. On the other hand, rough walls enhance the overall drag. In this work, we inject bubbles into turbulent Taylor-Couette flow with rough walls (with a Reynolds number up ...
Berg, Thomas H. van den +3 more
core +2 more sources
Journal of Marine Science and EngineeringThis review paper investigates the use of air lubrication to reduce ship hull skin frictional drag, a technology whose fundamental drag-reduction mechanisms and impact on seakeeping are increasingly being studied through Computational Fluid Dynamics (CFD)
David Hitchmough +6 more
doaj +1 more source
Drag Reduction And Heating [PDF]
Progress in Canadian Mechanical Engineering, 2018 Paper presented at 2018 Canadian Society of Mechanical Engineers International Congress, 27-30 May 2018. ; An external force is required to maintain the relative movement of horizontal plates. It is shown that this force is reduced when the plates are subject to a spatially distributed heating.
Floryan, Jerzy M. +2 more
openaire +2 more sources
Drag Reduction by Polymers in Wall Bounded Turbulence
, 2004 We address the mechanism of drag reduction by polymers in turbulent wall bounded flows. On the basis of the equations of fluid mechanics we present a quantitative derivation of the "maximum drag reduction (MDR) asymptote" which is the maximum drag ...
A. N. Beris +8 more
core +1 more source
Numerical analysis of drag reduction of hydrofoil appendage for high-speed ship
Zhongguo Jianchuan Yanjiu, 2022 ObjectiveIn order to reduce the wave-making resistance of high-speed ships, this paper proposes an innovative hydrofoil appendage with a drag reduction effect.
Qian CHEN +3 more
doaj +1 more source
Quantitative Analysis of Drag Reduction Methods for Blunt Shaped Automobiles
Applied Sciences, 2020 In fluid mechanics, drag related problems aim to reduce fuel consumption. This paper is intended to provide guidance for drag reduction applications on cars.
Ferenc Szodrai
doaj +1 more source