Determining the Stratification of Exchange Flows in Sea Straits

2003 ◽  
Author(s):  
Lawrence J. Pratt ◽  
Karl R. Helfrich
Keyword(s):  
Exchange Flows ◽  
Sea Straits

Dynamics of the Baltic Sea straits via numerical simulation of exchange flows

2018 ◽  
Vol 131 ◽  
pp. 40-58 ◽  
Author(s):  
E.V. Stanev ◽  
J. Pein ◽  
S. Grashorn ◽  
Y. Zhang ◽  
C. Schrum
Keyword(s):  
Numerical Simulation ◽  
Baltic Sea ◽  
The Baltic Sea ◽  
Exchange Flows ◽  
Sea Straits ◽  
The Baltic

Unsteady two-layer hydraulic exchange flows with friction

2009 ◽  
Vol 633 ◽  
pp. 99-114 ◽  
Author(s):  
S. S. LI ◽  
G. A. LAWRENCE
Keyword(s):  
Exchange Rate ◽  
Flow Rate ◽  
Laboratory Experiments ◽  
Time Dependent ◽  
Forced Flow ◽  
Exchange Flow ◽  
Interface Position ◽  
Exchange Flows ◽  
Sea Straits ◽  
Flow Through

Two-layer exchange flow through a contraction with both friction and barotropic forcing is modelled in terms of three parameters reflecting the friction and the strength and period of the barotropic forcing. In the appropriate limits, the results for steady flow with and without friction, and inviscid barotropically forced flow are recovered. The predicted time-dependent interface position compares well with laboratory experiments, improving on the inviscid formulation. The concurrent effects of friction and barotropic forcing on average exchange flow rate are determined. When friction is weak barotropic forcing increases the exchange rate. However, when friction is high, tidal forcing can result in a reduced exchange rate, a phenomena that we call tidal inhibition. When friction is weak maximal exchange occurs throughout the tidal cycle, but as friction is increased submaximal flow develops for longer and longer periods. As friction is increased even further the flow becomes hydraulically uncontrolled. The parameter range for major sea straits includes tidally enhanced and tidally inhibited flows, as well as maximal, submaximal and uncontrolled flows.

scholarly journals Buoyancy-driven exchange flows in inclined ducts

2020 ◽  
Vol 893 ◽  
Author(s):  
Adrien Lefauve ◽  
P. F. Linden
Keyword(s):  
Exchange Flows ◽  
Image Position

Scale-dependent spatial variabilities of hydrological exchange flows and transit time in a large regulated river

2021 ◽  
Vol 598 ◽  
pp. 126283
Author(s):  
Xuehang Song ◽  
Yilin Fang ◽  
Jie Bao ◽  
Huiying Ren ◽  
Zhuoran Duan ◽  
...  
Keyword(s):  
Transit Time ◽  
Regulated River ◽  
Exchange Flows ◽  
Hydrological Exchange

scholarly journals Dam Operations and Subsurface Hydrogeology Control Dynamics of Hydrologic Exchange Flows in a Regulated River Reach

2018 ◽  
Author(s):  
Pin Shuai ◽  
Xingyuan Chen ◽  
Xuehang Song ◽  
Glenn Hammond ◽  
John Zachara ◽  
...  
Keyword(s):  
Regulated River ◽  
Exchange Flows ◽  
River Reach ◽  
Hydrologic Exchange

Unsteady convective exchange flows in cavities

1998 ◽  
Vol 368 ◽  
pp. 127-153 ◽  
Author(s):  
J. J. STURMAN ◽  
G. N. IVEY
Keyword(s):  
Boundary Layer ◽  
Steady State ◽  
Boundary Layer Thickness ◽  
Buoyancy Flux ◽  
Exchange Flow ◽  
Flushing Time ◽  
Exchange Flows ◽  
Buoyancy Forcing ◽  
Convective Exchange ◽  
Approach To Steady State

Horizontal exchange flows driven by spatial variation of buoyancy fluxes through the water surface are found in a variety of geophysical situations. In all examples of such flows the timescale characterizing the variability of the buoyancy fluxes is important and it can vary greatly in magnitude. In this laboratory study we focus on the effects of this unsteadiness of the buoyancy forcing and its influence on the resulting flushing and circulation processes in a cavity. The experiments described all start with destabilizing forcing of the flows, but the buoyancy fluxes are switched to stabilizing forcing at three different times spanning the major timescales characterizing the resulting cavity-scale flows. For destabilizing forcing, these timescales are the flushing time of the region of forcing, and the filling-box timescale, the time for the cavity-scale flow to reach steady state. When the forcing is stabilizing, the major timescale is the time for the fluid in the exchange flow to pass once through the forcing boundary layer. This too is a measure of the time to reach steady state, but it is generally distinct from the filling-box time. When a switch is made from destabilizing to stabilizing buoyancy flux, inertia is important and affects the approach to steady state of the subsequent flow. Velocities of the discharges from the end regions, whether forced in destabilizing or stabilizing ways, scaled as u∼(Bl)1/3 (where B is the forcing buoyancy flux and l is the length of the forcing region) in accordance with Phillips' (1966) results. Discharges with destabilizing and stabilizing forcing were, respectively, Q−∼(Bl)1/3H and Q+∼(Bl)1/3δ (where H is the depth below or above the forcing plate and δ is the boundary layer thickness). Thus Q−/Q+>O(1) provided H>O(δ), as was certainly the case in the experiments reported, demonstrating the overall importance of the flushing processes occurring during periods of cooling or destabilizing forcing.

Sign in / Sign up

Export Citation Format

Share Document