EM 1110-2-1100 (Part II)
30 Apr 02
Figure II-6-17. Sample tides and currents for an ocean-inlet-bay system that satisfy the Keulegan assumptions
Vavg = maximum velocity averaged over entire cross section
Vmeas = point measurement of maximum velocity
R = hydraulic radius of entire cross section
D = depth of water at current meter location
The Vavg value then can be used in Equation II-6-13.
d. Determining important inlet parameters.
Graphs can easily
to determine inlet hydraulics;
however, evaluation of important parameters requires some effort. Mason (1975) determined appropriate
techniques for defining cross-sectional area, bay area, inlet (channel) length, hydraulic radius, friction factor
and exit and entrance loss coefficients. The following offers guidance in the evaluation of parameters.
(1) Cross-sectional area. Problems in defining location and magnitude of the cross-sectional area result
in greatest variability in computed values of the repletion coefficient. To reduce such variability, the cross
section should be determined in the following manner:
Hydrodynamics of Tidal Inlets