Experimental study of surface pressure in three-dimensional turbulent jet/boundary interaction

AIAA Journal ◽  
1986 ◽  
Vol 24 (7) ◽  
pp. 1201-1203 ◽  
Author(s):  
Christos D. Tsitouras ◽  
Latif M. Jiji
Keyword(s):  
Experimental Study ◽  
Surface Pressure ◽  
Three Dimensional ◽  
Turbulent Jet ◽  
Boundary Interaction

Theoretical and experimental study of electrochemical reactors with three-dimensional bipolar electrodes

2009 ◽  
Vol 40 (3) ◽  
pp. 709-718 ◽  
Author(s):  
O. González Pérez ◽  
J. M. Bisang
Keyword(s):  
Experimental Study ◽  
Three Dimensional ◽  
Electrochemical Reactors ◽  
Bipolar Electrodes

Experimental study on the distribution of earth pressure and surface settlement through three-dimensional trapdoor tests

2003 ◽  
Vol 18 (2-3) ◽  
pp. 171-183 ◽  
Author(s):  
Toshihisa Adachi ◽  
Makoto Kimura ◽  
Kiyoshi Kishida
Keyword(s):  
Experimental Study ◽  
Three Dimensional ◽  
Earth Pressure ◽  
Surface Settlement

Obstacle drag in stratified flow

1990 ◽  
Vol 429 (1876) ◽  
pp. 119-140 ◽  
Keyword(s):  
Experimental Study ◽  
Linear Density ◽  
Three Dimensional ◽  
Inviscid Flow ◽  
Force Balance ◽  
Video Recordings ◽  
Lee Waves ◽  
Time Variations ◽  
Obstacle Height ◽  
Stable Linear

This paper describes an experimental study of the drag of two- and three-dimensional bluff obstacles of various cross-stream shapes when towed through a fluid having a stable, linear density gradient with Brunt-Vaisala frequency, N . Drag measurements were made directly using a force balance, and effects of obstacle blockage ( h / D , where h and D are the obstacle height and the fluid depth, respectively) and Reynolds number were effectively eliminated. It is shown that even in cases where the downstream lee waves and propagating columnar waves are of large amplitude, the variation of drag with the parameter K ( = ND /π U ) is qualitatively close to that implied by linear theories, with drag minima existing at integral values of K . Under certain conditions large, steady, periodic variations in drag occur. Simultaneous drag measurements and video recordings of the wakes show that this unsteadiness is linked directly with time-variations in the lee and columnar wave amplitudes. It is argued that there are, therefore, situations where the inviscid flow is always unsteady even for large times; the consequent implications for atmospheric motions are discussed.

scholarly journals An experimental study of secondary oil migration in a three-dimensional tilted porous medium

AAPG Bulletin ◽  
2012 ◽  
Vol 96 (5) ◽  
pp. 773-788 ◽  
Author(s):  
Jianzhao Yan ◽  
Xiaorong Luo ◽  
Weimin Wang ◽  
Renaud Toussaint ◽  
Jean Schmittbuhl ◽  
...  
Keyword(s):  
Experimental Study ◽  
Porous Medium ◽  
Three Dimensional ◽  
Oil Migration

An experimental study of the influence of riblets on transition

1996 ◽  
Vol 315 ◽  
pp. 31-49 ◽  
Author(s):  
G. R. Grek ◽  
V. V. Kozlov ◽  
S. V. Titarenko
Keyword(s):  
Experimental Study ◽  
Three Dimensional ◽  
Negative Influence ◽  
Positive Influence ◽  
Linear Stage ◽  
Turbulent Transition ◽  
Transition Structures ◽  
Stage Transition ◽  
Tollmien Schlichting ◽  
Laminar Turbulent Transition

An experimental study of the effect of riblets on three-dimensional nonlinear structures, the so-called Λ-vortices on laminar-turbulent transition showed that riblets delay the transformation of the Λ-vortices into turbulent spots and shift the point of transition downstream. This result is opposite to the negative influence of such ribbed surfaces on two-dimensional linear Tollmien-Schlichting waves (the linear stage of transition). Thus, the ribbed surface influences laminar-turbulent transition structures differently: a negative influence on the linear-stage transition structures and a positive influence on the nonlinear-stage transition structures. It is demonstrated that transition control by means of riblets requires special attention to be paid to the choice of their location, taking into account the stage of transition.

Airborne Submicron Particle Accumulates at Leaf Stomata Rather than Non-Stomatal Areas: A Contrast Experimental Study by Using Three-Dimensional X-Ray Microscopy

2021 ◽  
Author(s):  
Dele Chen ◽  
Shan Yin ◽  
Xuyi Zhang ◽  
Junyao Lyu ◽  
Yiran Zhang ◽  
...  
Keyword(s):  
Experimental Study ◽  
Three Dimensional ◽  
Submicron Particle ◽  
X Ray

Computational Investigation of Thrust Production of a Dolphin at Various Swimming Speeds

2021 ◽  
Author(s):  
Junshi Wang ◽  
Vadim Pavlov ◽  
Zhipeng Lou ◽  
Haibo Dong
Keyword(s):  
Surface Pressure ◽  
Swimming Performance ◽  
Three Dimensional ◽  
Numerical Approach ◽  
Immersed Boundary ◽  
Reconstruction Method ◽  
Force Coefficient ◽  
Speed Increase ◽  
Generation Mechanisms ◽  
Thrust Production

Abstract Dolphins are known for their outstanding swimming performance. However, the difference in flow physics at different speeds remains elusive. In this work, the underlying mechanisms of dolphin swimming at three speeds, 2 m/s, 5 m/s, and 8 m/s, are explored using a combined experimental and numerical approach. Using the scanned CAD model of the Atlantic white-sided dolphin (Lagenorhynchus acutus) and virtual skeleton-based surface reconstruction method, a three-dimensional high-fidelity computational model is obtained with time-varying kinematics. A sharp-interface immersed-boundary-method (IBM) based direct numerical simulation (DNS) solver is employed to calculate the corresponding thrust production, wake structure, and surface pressure at different swimming speeds. It is found that the fluke keeps its effective angle of attack at high values for about 60% of each stroke. The total pressure force coefficient along the x-axis converges as the speed increase. The flow and surface pressure analysis both show considerable differences between lower (2 m/s) and higher (5 m/s and 8 m/s) speeds. The results from this work help to bring new insight into understanding the force generation mechanisms of the highly efficient dolphin swimming and offer potential suggestions to the future designs of unmanned underwater vehicles.

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