USER MANUAL SWAN Cycle III version 40.72A

52 Chapter 4
4.5.4 Physics
GEN1 [cf10] [cf20] [cf30] [cf40] [edmlpm] [cdrag] [umin] [cfpm]
With this command the user indicates that SWAN should run in first-generation mode
(see Scientific/Technical documentation).
[cf10]
[cf20]
[cf30]
[cf40]
[edmlpm]
[cdrag]
[umin]
[cfpm]
controls the linear wave growth.
Default: [cf10] = 188.
controls the exponential wave growth.
Default: [cf20] = 0.59
controls the exponential wave growth.
Default: [cf30] = 0.12
controls the dissipation rate, i.e., the time decay scale.
Default: [cf40] = 250.
maximum non-dimensionless energy density of the wind sea part of the spectrum
according to Pierson Moskowitz.
Default: [edmlpm] = 0.0036
drag coefficient.
Default: [cdrag] = 0.0012
minimum wind velocity (relative to current; all wind speeds are taken at 10m above
sea level).
Default: [umin] = 1.
coefficient which determines the Pierson Moskowitz frequency:
σ PM = 2π g [cfpm] /U 10
Default: [cfpm] = 0.13
GEN2 [cf10] [cf20] [cf30] [cf40] [cf50] [cf60] [edmlpm] [cdrag] [umin] [cfpm]
With this command the user indicates that SWAN should run in second-generation mode
(see Scientific/Technical documentation). The variables are identical to those in the GEN1
command except that [cf50] and [cf60] are added.
[cf50]
[cf60]
controls the spectral energy scale of the limit spectrum.
Default: [cf50] = 0.0023
controls the spectral energy scale of the limit spectrum.
Default: [cf60] = −0.223