In recent years, it has become important to evaluate whether ship propulsive performance achieves the design performance not only in a calm sea condition but also in a seaway. Various on-board monitoring systems have been developed and fitted on-board to check the performance of ships in a seaway. The evaluation can also be fed back to a new ship design. A method for prediction of ship performance in actual seas based on a physical model is described here. Prediction of steady forces in waves, wind forces, drift forces, and steering forces is described from the viewpoint of accurate practical prediction. The prediction of the engine operating point in winds and waves is also treated here. Examples of these prediction methods are illustrated. Performance analysis by an on-board monitoring system using the performance prediction method discussed here is described in the Part 2 of this paper.
Continuous measurement of waves, ship motions (roll and pitch), and so on has been carried out for about five years by onboard monitoring system installed ocean-going vessel. Measured wave data, including wave height, wave period and wave direction, are thoroughly evaluated with corresponding onboard weather observation data by comparing directly in terms of time series and statistical values.
Then, short term prediction of ship motions (roll and pitch) based on the measured wave data are compared with onboard motion data measured by vertical gyro.
From the results described, good accuracy and effectiveness of wave measurements by an onboard radar wave meter for safe navigation are demonstrated.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations鈥揷itations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.