Analysis for the powering performance of dry cargo ship in operation

Abstract

The full-scale measurement system is to necessary to obtain a feedback on the ship powering performance during an operation or a period of ship life. In addition, economical operation with optimized routing is also possible with the use of a ship performance measurement. In this paper, the results of onboard measurements and analysis of powering performance for the dry cargo ship are presented. Onboard measurements had been conducted during a month and a half operating in the southern Atlantic route. Several items related with the powering performance such as the ship position, the speed over ground, the speed through the water, the shaft torque, the propeller speed, the rudder angle, the ship heading, the draughts at the fore and after perpendiculars, the wind direction, the wind speed, and the seawater depth are measured in the real ship. The weather data which are related to the current, wave and swell is obtained from the public weather service. The measured operational data and obtained weather data are combined to analyze the powering performance of the operating ship. Resistance calculation and power correction method of ISO15016:2015 are used to evaluate the powering performance in calm water. Analysis results are compared with model test results to investigate the effects of hull fouling and in-service degradation of ship performance. Copyright ？ 2018 by the International Society of Offshore and Polar Engineers (ISOPE)