TY - JOUR
T1 - Effect of the water depth on oscillatory flows over a flat plate: from the intermittent towards the fully turbulent regime
AU - Kaptein, S.J.
AU - Duran Matute, M.
AU - Roman, Federico
AU - Armenio, V.
AU - Clercx, H.J.H.
PY - 2019/10/1
Y1 - 2019/10/1
N2 - We performed high-resolution numerical simulations of a turbulent flow driven by an oscillating uniform pressure gradient. The purpose was to investigate the influence of a reduced water depth h on the structure and dynamics of the turbulent boundary layer and the transition towards a fully turbulent flow. The study is motivated by applications of oscillatory flows, such as tides, in which h is of the same order of magnitude as the thickness of the turbulent boundary layer δ. It was found that, if h∼ δ, the turbulent flow is characterized by (1) an increase of the magnitude of the surface velocity, (2) an increase in the magnitude of the wall shear stress and (3) a phase lead of the velocity profiles, all with respect to the reference case for which h≫ δ. These results are in agreement with analytical solutions for a laminar oscillatory flow. Nevertheless, if the value of the Reynolds number is too small and h∼ δ, the flow relaminarizes.
AB - We performed high-resolution numerical simulations of a turbulent flow driven by an oscillating uniform pressure gradient. The purpose was to investigate the influence of a reduced water depth h on the structure and dynamics of the turbulent boundary layer and the transition towards a fully turbulent flow. The study is motivated by applications of oscillatory flows, such as tides, in which h is of the same order of magnitude as the thickness of the turbulent boundary layer δ. It was found that, if h∼ δ, the turbulent flow is characterized by (1) an increase of the magnitude of the surface velocity, (2) an increase in the magnitude of the wall shear stress and (3) a phase lead of the velocity profiles, all with respect to the reference case for which h≫ δ. These results are in agreement with analytical solutions for a laminar oscillatory flow. Nevertheless, if the value of the Reynolds number is too small and h∼ δ, the flow relaminarizes.
KW - Large eddy simulation
KW - Oscillatory flow
KW - Shallow flow
KW - Turbulence
UR - http://www.scopus.com/inward/record.url?scp=85062033705&partnerID=8YFLogxK
U2 - 10.1007/s10652-019-09671-3
DO - 10.1007/s10652-019-09671-3
M3 - Article
SN - 1567-7419
VL - 19
SP - 1167
EP - 1184
JO - Environmental Fluid Mechanics
JF - Environmental Fluid Mechanics
IS - 5
ER -