EM 1110-2-1100 (Part II)
30 Apr 02
V = average velocity in channel
h = channel water surface elevation
R = hydraulic radius
(4) Keulegan neglected local acceleration (the first term in Equation II-6-2) and integrated the equation
over the length of the inlet. Using the equation of continuity for flow through the inlet into the bay:
dhb
V Aavg ' Ab
(II-6-3)
dt
where
Aavg = average area over the channel length
Ab = surface area of bay
dhb/dt = change of bay elevation with time
(5) Combining Equations II-6-2 and II-6-3, Keulegan developed a solution for velocity and resulting bay
tide which contained the dimensionless parameter K, known as the coefficient of repletion, or filling, which
is defined as
T Aavg
2g
K'
(II-6-4)
2 π Ab
fL
ao ken % kex %
4R
where Aavg, AB , g, f, and R are as defined above, and
T = tidal period
aO = ocean tide amplitude (one-half the ocean tide range)
ken = entrance energy loss coefficient
kex = exit energy loss coefficient
L = inlet length
R = inlet hydraulic radius (see Equation II-6-18)
Hydrodynamics of Tidal Inlets
II-6-9
Previous Page
