Recommended Values

The maximum number of iterations has a default value of 500.

Using the modified Newton-Raphson method the default value for the relaxa­tion factor is 0.1. In general a high factor will give a fast convergence, how­ever the iteration sequence may diverge. Hence, to ensure convergence a small value must be used.

Using the method based on iteration in the time domain the maximum num­ber of iteration must normally be very high to ensure convergence and the tol­erance must be very small. The maximum number of iteration times the time step used in the algorithm must be larger that the time it takes for the waves to propagate through the computational domain. If the tolerance is too high the algorithm may stop before the steady state solution is obtained. Note that in case the increment rate of spectral energy in time becomes too large (e.g. for very high wind speeds), the model will automatically limit the spectral energy in order to ensure stability in the numerical solution. You can read more about this in the section Time Integration in the scientific documenta­tion.

It is strongly recommended to use the modified Newton-Raphson method.