A Nonlinear Frequency Domain Simulation for SWATH Craft

The development of a nonlinear frequency domain simulation which accommodates frequency independent nonlinearities is described. Although developed around the dynamics of a particular naval craft, the simulation can be applied to the most general situation and need not be restricted solely to the pr...

Full description

Saved in:
Bibliographic Details
Main Author: Livingston,Walter H
Format: Report
Language:English
Subjects:
AUTOMATIC
COMPUTERIZED SIMULATION
CONTROL
DIFFERENTIAL EQUATIONS
EQUATIONS OF MOTION
Fluid Mechanics
FREQUENCY
Frequency domain simulation
HEAVING
HYDRODYNAMICS
Marine Engineering
MATHEMATICAL MODELS
MATHEMATICAL PREDICTION
NAVAL VESSELS
NONLINEAR SYSTEMS
OPEN LOOP SYSTEMS
PE61153N
PITCH(MOTION)
SHIP MOTION
SWATH(Small Waterplane Area Twin Hulls)
WU11572145
Online Access:Request full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The development of a nonlinear frequency domain simulation which accommodates frequency independent nonlinearities is described. Although developed around the dynamics of a particular naval craft, the simulation can be applied to the most general situation and need not be restricted solely to the prediction of ship motions. The workability and usefulness of the simulation is demonstrated by carrying out three scenarios with the SWATH 6A craft. Two scenarios are open loop; the third includes automatic control. These scenarios are also simulated in the time domain using a generalized nonlinear time domain simulation which is based on the same modeling of the craft dynamics that is used for the nonlinear frequency domain simulation. The results obtained with these simulations agree for each of the scenarios simulated. When the results obtained with the nonlinear frequency domain simulation are contrasted with those obtained with a linear frequency domain simulation which employs equivalent linearization, the lack of agreement is noticeable. This highlights the limited usefulness of equivalent linearization. (Author)