Page 114 - Pipelines and Risers
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Hydrodynamics around Pipes 87
Figure 2D regular long-crested waves.
q = a .sin(ot -kx + a)
Fluid velocity component in the x-direction,
agk cosh(k(d+z)) .
v =-. . sin(ot - kx + a)
0 cosh(kd)
Fluid velocity component in the z-direction,
Fluid acceleration component in the x-direction,
Fluid acceleration component in the z-direction,
sinh(k(d + z)) .
a, =-agk. . sin(ot - kx + a)
cosh(kd)
Dynamic pressure,
(6.9)
6.3.3 2D Random Long-Crested Waves
The 2D random long-crested wave (Figure 6.5) formulation is based on the use of a wave
spectrum (Figure 6.3). Input of significant wave height, peak frequency, etc. (input is
dependent on type of wave spectrum) defines the characteristics of the sea-state.
As an example, the JONSWAP spectrum can be defined as:
(6.10)
where:
0 Angular frequency
