船の速力試運転解析法の検証

－プロペラ荷重度による自航要素の変化を考慮できる新しい試運転解析法－

抄録

In this paper, two speed trial analysis methods are newly presented taking a change of self-propulsion factors due to propeller load change into account by a different approach from Direct Power Method (DPM)²⁾ which is the only method taking the change of self-propulsion factors into account. One is a method derived based on the equations representing the balance of propeller thrust and hull resistance, and propeller torque and delivered power by a Taylor expansion technique on the assumption that corrected propeller revolution is small, and this is called Taylor Expansion Method (TEM), here. Another is a method extended the Taniguchi and Tamura Method¹⁾ to account the change of self-propulsion factors, and this is called improved Taniguchi and Tamura Method (iTTM). Special feature of the methods is not to require the information of constants (εP and εn), and propulsive efficiency in no disturbance condition (ηid), which are indispensable for DPM. To verify the present methods, virtual speed trial data are theoretically generated in different wind conditions and the present methods are applied to eliminate the external disturbance effects from the virtual speed trial data. The obtained relationship for ship speed, propeller revolution, and delivered power is compared with the true results and the corrected results obtained by using the DPM. The present methods, TEM and iTTM, are more accurate than the DPM even though there are fewer input parameters than for the DPM.