Boundary-layer flow and bed shear stress under a solitary wave: revision

2014 ◽  
Vol 753 ◽  
pp. 554-559 ◽  
Author(s):  
Yong Sung Park ◽  
Joris Verschaeve ◽  
Geir K. Pedersen ◽  
Philip L.-F. Liu
Keyword(s):  
Boundary Layer ◽  
Shear Stress ◽  
Solitary Wave ◽  
Boundary Layer Flow ◽  
Bottom Boundary Layer ◽  
Bed Shear Stress ◽  
Bottom Boundary ◽  
Layer Flow

AbstractWe address two shortcomings in the article by Liu, Park & Cowen (J. Fluid Mech., vol. 574, 2007, pp. 449–463), which gave a theoretical and experimental treatise of the bottom boundary-layer under a solitary wave.

Boundary layer flow and bed shear stress under a solitary wave

2007 ◽  
Vol 574 ◽  
pp. 449-463 ◽  
Author(s):  
PHILIP L.-F. LIU ◽  
YONG SUNG PARK ◽  
EDWIN A. COWEN
Keyword(s):  
Boundary Layer ◽  
Shear Stress ◽  
Solitary Wave ◽  
Analytical Solutions ◽  
Boundary Layer Flow ◽  
Inertia Force ◽  
Bed Shear Stress ◽  
Viscous Boundary Layer ◽  
Layer Flow ◽  
Viscous Boundary

Liu & Orfila (J. Fluid Mech. vol. 520, 2004, p. 83) derived analytical solutions for viscous boundary layer flows under transient long waves. Their analytical solutions were obtained with the assumption that the nonlinear inertia force was negligible in the momentum equations. In this paper, using Liu & Orfila's solution and the solutions for the nonlinear boundary layer equations, we examine the boundary layer flow characteristics under a solitary wave. It is found that while the horizontal component of the free-stream velocity outside the boundary layer always moves in the direction of wave propagation, the fluid particle velocity near the bottom inside the boundary layer reverses direction as the wave decelerates. Consequently, the bed shear stress also changes sign during the deceleration phase. Laboratory measurements, including the free-surface displacement, particle image velocimetry (PIV) resolved velocity fields of the viscous boundary layer, and the calculated bed shear stress were also collected to check the theoretical results. Excellent agreement is observed.

Estimating Turbulence and Shear Stress under Regular Waves from ADV Data

2012 ◽  
Vol 212-213 ◽  
pp. 1083-1091
Author(s):  
Zheng Xiao ◽  
Chao Shen ◽  
Zhi Xin Guan ◽  
Yuan Li ◽  
Rui Min Ji
Keyword(s):  
Boundary Layer ◽  
Shear Stress ◽  
Bottom Boundary Layer ◽  
Wave Flow ◽  
Shear Stresses ◽  
Coastal Morphology ◽  
Bottom Boundary ◽  
Sand Ripples ◽  
Laboratory Flume ◽  
Layer Flow

The boundary layer flow determines the bottom shear stresses, which is key point for sediment transport and thereby the evolution of coastal morphology. The structure of the bottom boundary layer in coastal seas has been of interest to oceanographers for many years. In the paper Acoustic Doppler velocimeter (ADV) technique is applied to measure the bottom boundary layer under cnoidal waves in a laboratory flume with 40-m-long, 0.5-m-wide, and 0.8-m-deep.. Based on the high frequency turbulence signal collected, statistic parameters of cnoidal wave flow are calculated, compared and analyzed. The turbulent structure over plain bed and sand ripples bed are carefully studied. The turbulence intensity of near-bed velocities changes along depth of several phases in a period is analyzed. Turbulent Kinetic Energy Method (TKE Method) is used to estimate near-bed shear stress on flat and slope.

Sign in / Sign up

Export Citation Format

Share Document