Download Wasim User Manual

Wasim
SESAM
1-2
28-MAR-2011
Program version 5.1
The following non-linear effects are included with the non-linear option:
• Integration of Froude-Krylov and hydrostatic pressure over exact wetted surface.
• Quadratic terms in Bernoulli are included.
• Exact treatment of rotation angles in inertia and gravity terms.
• Quadratic roll damping.
The radiation/diffraction problem is solved on the mean free surface and mean wetted surface with both the
linear and non-linear option.
Wasim consists of several different executable elements:
Wasim_Mass
Computes body mass matrix and sectional mass matrices from a given mass model.
Wasim_Setup
Sets up and inverts the influence matrix for the radiation/diffraction problem,
solves for the basis flow (i.e. the solution in calm water). The computations in
Wasim_Setup must only be redone when the panel model is changed on the hull or
on the free surface.
Wasim_Solve
performs the time domain simulation.
Wasim_Fourier
performs the transformation from time domain to frequency domain. This program
can analyse time records from many different runs with Wasim_Solve and merge
all the data into a single Hydrodynamic Results Interface File (G1.SIF)
Wasim_Stru
load transfer from panel model to FEM model.
1.2
Wasim in the SESAM System
Wasim is an integrated part of the SESAM suite of programs, with interfaces to SESAM Pre and Post processors and the structural analysis module Sestra.
The mass model and the finite element model (i.e. the model to receive hydrodynamic loading) can be given
as a SESAM superelement model. Often these are the same model. The geometry input can be exported
from the Nauticus Hull system. The Wasim Manager will create the panel model from this geometry input.
The time domain output can be processed by the post processor Postresp_time. The frequency domain output can be processed by the post processor Postresp.
Animation output can be viewed by Xtract.
Figure 1.1 shows the SESAM Overview. A description of the input and output files is given in Chapter 3.
See also Figure 3.1.