USER MANUAL SWAN Cycle III version 40.72A

26 Chapter 4
1 : warnings,
2 : errors (possibly automatically repaired or repairable by SWAN),
3 : severe errors.
Default: [maxerr] = 1.
[grav] is the gravitational acceleration (in m/s 2 ).
Default: [grav] = 9.81.
[rho] is the water density ρ (in kg/m 3 ).
Default: [rho] = 1025.
[inrhog] to indicate whether the user requires output based on variance or based on true
energy (see Section 2.5).
[inrhog] = 0 : output based on variance
[inrhog] = 1 : output based on true energy
Default: [inrhog] = 0.
[hsrerr] the relative difference between the user imposed significant wave height and the
significant wave height computed by SWAN (anywhere along the boundary of
structured grid) above which a warning will be given. This relative difference
is the difference normalized with the user provided significant wave height.
This warning will be given for each boundary grid point where the problem occurs
(with its x− and y−index number of the computational grid). The cause of the
difference is explained in Section 2.6.3. To supress these warnings (in particular
for nonstationary computations), set [hsrerr] at a very high value or use
command OFF BNDCHK.
Default: [hsrerr] = 0.10.
NAUTICAL indicates that the Nautical convention for wind and wave direction (SWAN input
and output) will be used instead of the default Cartesian convention.
For definition, see Section 2.5 or Appendix A.
CARTESIAN indicates that the Cartesian convention for wind and wave direction (SWAN input
[pwtail]
and output) will be used. For definition, see Section 2.5 or Appendix A.
power of high frequency tail; defines the shape of the spectral tail above the
highest prognostic frequency [fhigh] (see command CGRID). The energy density
is assumed to be proportional to frequency to the power [pwtail].
Default values depend on formulations of physics:
command GEN1 : [pwtail] = 5
command GEN2 : [pwtail] = 5
command GEN3 KOMEN : [pwtail] = 4
command GEN3 JANSEN : [pwtail] = 5
If the user wishes to use another value, then this SET command should be
located in the command file after the GEN1, GEN 2 or GEN3 command
(these will override the SET command with respect to [pwtail]).
[froudmax] is the maximum Froude number (U/ √ gd with U the current and d the water
depth). The currents taken from a circulation model may mismatch with given
water depth d in the sense that the Froude number becomes larger than 1.
For this, the current velocities will be maximized by Froude number times √ gd.