************** EXAMPLE problem ***************
GIVEN: A wave in depth d = 200 feet, with period T = 9 seconds, and a
maximum bottom velocity uztkzx(-J) 2 1.0 foot per second.
FIND: The minimum wave height that will create the given bottom velocity.
SOLUTION: Calculate
gT2
L = ---°
2rr
= 5.12 (9)2
= 415 feet .
and
d _ 200^
Lo ” 415
= 0.482
Entering Figure 4-20 with d/Lo = 0.482, détermine
u
max(-d)
0.30
rhus a 30-foot minimum wave height with a 9-second wave period is needed
to create a bottom velocity equal to or greater than 1 foot per second
in 200 feet of water. Altematively, a curve for a 9-second period can
be interpolated in Figure 4-21 and umax(-^T/H can be read from the
curve's intersection with the 200-foot depth.
*************************************
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4-64