Turbulent drag reduction control
Turbulent skin friction drag reduction control by spanwise motion
... actively control turbulent boundary layer for the tur- bulent skin-friction drag reduction with Direct Numerical ...understand drag reduction mechanism in simple spanwise wall ...
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Drag reduction via turbulent boundary layer flow control
... skin-friction drag reduction through passive and active flow control is still at an early stage in its devel- ...body-force control strate- gies have been shown to give drag reductions ...
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Effectiveness of active flow control for turbulent skin friction drag reduction
... flow control to reduce turbulent skin friction drag is of paramount importance in many engineering applications, including aerospace engineering, where the skin friction component is approximately ...
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Toward Understanding Underlying Mechanisms of Drag Reduction in Turbulent Flow Control
... underlying drag-reduction mechanisms of three flow-control strategies, namely polymer additives, slip surfaces, and external body forces, are investigated by utilizing two temporal turbulent ...
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Skin-Friction Drag Reduction in a Turbulent Channel Flow based on Wall Shear-Free Control
... flow control of wall-bounded turbulent flow for skin-friction drag reduction (DR) has been received great attention in recent years due to large economical and ecological ...of ...
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Turbulent drag reduction through oscillating discs
... other drag reduction ...feedback control systems studied by Yoshino et ...comparable drag-reduction values for even larger oscillation periods and diameters, which are denoted by the ...
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Turbulent Drag Reduction by Spanwise Wall Oscillations
... a control surface is defined to be that which encloses the entire computational domain, a simple momentum balance in streamwise direction results in the following ...
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Turbulent drag reduction using surface plasma
... The mechanical spanwise oscillation described above is clearly effective in reducing skin-friction; with a maximum of 45% drag reduction quoted by most authors. However, the oscillation method is not very ...
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Turbulent drag reduction through wall-forcing methods
... of control on the different statistics and here more particularly the Reynolds-shear ...skin-friction drag-reduction coefficient through the FIK ...dominating control method behaviour. Note ...
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Zero mass jets for turbulent flow drag reduction
... a drag reduction can be achieved by adapting ZMJ. The drag reduction has been obtained by changing jet angle β ...the control method, as shown in figure ...unique control method, ...
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Turbulent Friction Drag Reduction Using Electroactive Polymer Surfaces
... 4.5 3D Traverse mechanism A 3-dimensional traverse system consisting of two computer-controlled axes (the spanwise and the wall-normal) and a manual third axis (the streamwise) was designed and built over the roof of the ...
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Drag Reduction by Laminar Flow Control
... fully turbulent simulations were performed, aimed at the identification of a suitable numerical setup for the simulations including suction and providing the drag coefficient of a turbulent fuselage ...
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Wall oscillation induced drag reduction zone in a turbulent boundary layer
... turbulence control with the objective of reducing skin friction drag has been a subject of intense research in recent times because of the implied energy and cost ...
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The effect of Reynolds number on turbulent drag reduction by streamwise travelling waves
... the turbulent flow control method using streamwise travelling waves (Quadrio et ...on turbulent skin-friction drag ...a turbulent channel flow subjected to the streamwise travelling ...
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A numerical study of turbulent drag reduction using streamwise travelling waves of spanwise wall velocity
... of control parameters for the streamwise travelling wave forcing up to Re τ = ...the drag reduction decreases with increased Re, and that the rate of decrease is heavily dependent on the ...
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An In depth Study on Drag Reduction of Turbulent Channel Flow Induced by Spatially Oscillating Lorentz Force
... Keywords: Turbulent channel flow, Pseudo-spectral method, Drag reduction, Lorentz ...turbulence control and drag reduction in a channel flow by using a spatially oscillating ...
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Experimental Investigation of Drag Reduction in Turbulent Flow Using Biological and Synthetic Macromolecules: A Comparative Study.
... 6 Fig. 2 Photograph of the experimental apparatus Three concentrations of 6 kinds of dilute polymeric solutions as a drag reducer were examined at three temperatures and flow rates in the device connected with two ...
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On the Effect of Rigid Swept Surface Waves on Turbulent Drag
... phase-averaged turbulent spanwise SSL flow was identical to the laminar solution, and used a linear analysis to estimate the net power gain by spatial Stokes layers of small characteristic ...dominant drag ...
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Low order modelling of flow control techniques for turbulent skin friction reduction
... spanwise control, coincides with that observed in the streamwise-independent EM, I 1,w ...oscillations control, exhibits a growth of the selected measure above 50% of the maximum obtained for an ...
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A mechanistic model of turbulent drag reduction by additives
... of drag reduction in walled turbulent flows of polymer solutions is theoretically ...a turbulent flow field is ...the turbulent flow field are elastic and ...a turbulent scale ...
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