Results 191 to 200 of about 8,471 (240)

Secondary flow induced by riblets

Journal of Fluid Mechanics, 1998
The effects of riblets on one wall of a channel bounding fully developed turbulent flow are investigated. Various perturbation elements including wires, fins and slots are modelled in order to understand the effects of riblets. It is found that widely spaced riblets, fins and wires create a substantial increase in turbulent activity just above ...
Goldstein, D. B., Tuan, T.-C.
openaire   +2 more sources

Influence of riblet geometry and freestream turbulence on boundary layer transition

The Physics of Fluids
High-fidelity large eddy simulations are used to investigate the influence of distributed surface-mounted riblets on spatially developing laminar boundary layer under varying freestream turbulence (FST).
Ishita Jain, S. Katiyar, S. Sarkar
semanticscholar   +1 more source

Natural Low-Frequency Riblets

Flow, Turbulence and Combustion, 1998
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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The Influence of Process Parameters on the Forming of Riblets during Riblet Rolling

Key Engineering Materials, 2014
In aeronautics, economic and environmental aspects become increasingly important. As those are very much influenced by the frictional drag of the airplane, a reduction of skin friction which causes a major portion of total aerodynamic drag is desirable.
Julia Pöplau, Sebastian Stille, Thijs Romans, Tilmann Beck, Lorenz Singheiser, Gerhard Hirt   +5 more
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Hierarchical nested riblet surface for higher drag reduction in turbulent boundary layer

The Physics of Fluids
Riblets can be potentially employed to passively reduce the turbulent friction drag. However, the drag reduction performance of riblets does not currently meet expectations, which could assist in emission reduction and energy conservation in green ...
Zhaoyang Ou, ZiDan Zhou, Wenyuan Zhou, Daoyuan Wang, Kun Zhang, Zeyu Kong, Yalin Tang, Yang He, Weizheng Yuan   +8 more
semanticscholar   +1 more source

Riblet drag at flight conditions

Journal of Aircraft, 1989
This paper describes perforated and nonperforated riblet tests on the fuselage of a modified Learjet model 28/29 twin-engine business jet at Reynolds numbers of 1.0-2.75 x 10/ft and Mach numbers of 0.3-0.7. Drag reductions of the order of 6% at nondimensional wall spacings of 12 were obtained using boundary-layer rakes and direct drag balances.
Michael J. Walsh, William L. Sellers, Catherine B. McGinley   +2 more
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Effects of bird feather-like convergent–divergent-riblet surfaces on the total pressure loss and wake turbulence of a transonic compressor cascade

The Physics of Fluids
The flow loss caused by the fan blades in a turbofan engine with a large bypass ratio is significant, and the wake considerably affects the inlet flow of downstream components.
Liyue Wang, Cong Wang, Gang Sun, Jinzhang Feng, Yunliang Zhang   +4 more
semanticscholar   +1 more source

Laminar boundary layer over riblets

Physics of Fluids, 1994
Laser doppler anemometry (LDA) measurements and numerical calculations have been made for a laminar boundary layer on triangular riblets. Calculated mean velocity distributions along the riblet contour are in good agreement with the measured ones. The results show that no transversal motion exists above and within the riblet valleys (e.g., no secondary
L. Djenidi, F. Anselmet, J. Liandrat, L. Fulachier   +3 more
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Low Air Drag Surface via Multilayer Hierarchical Riblets

ACS Applied Materials & Interfaces, 2021
Riblets inspired by shark skin exhibit a great air drag reduction potential in many industries, such as the aircraft, energy, and transportation industries. Many studies have reported that blade riblets attain the highest air drag reduction ability, with a current limit of ∼11%.
ZiDan Zhou, ShengKun Wang, ZeXiang Yan, DaoYuan Wang, JinJun Deng, Yang He, WeiZheng Yuan   +6 more
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Drag Reduction With Superhydrophobic Riblets

Volume 8: Mechanics of Solids, Structures and Fluids, 2012
Samples combining riblets and superhydrophobic surfaces are fabricated at University of Pittsburgh and their drag reduction properties are studied at the Center for Nanophase Materials Sciences (CNMS) in Oak Ridge National Laboratory with a commercial cone-and-plate rheometer. In parallel to the experiments, numerical simulations are performed in order
Charlotte Barbier, Elliot Jenner, Brian D’Urso   +2 more
openaire   +1 more source