某冷藏运输船有效功率的爱尔法估算分析

针对某冷藏运输船更换调距桨叶时需预先确定船体有效功率的问题,用爱尔法对弗劳德数、方形系数、爱尔系数和船体有效功率进行估算。文章介绍该冷藏船的主要参数;分析爱尔法估算船体有效功率的原理、计算表达式和爱尔标准船型参数;计算该冷藏船标准方形系数、爱尔系数,并根据实船方形系数、船宽比、浮心纵向坐标和水线长与标准值的差异分别修正爱尔系数;根据爱尔法估算不同船速的船体有效功率,并与实船试验计算结果进行比较。结果表明,爱尔法估算的船体有效功率与实船试验计算结果比较吻合,可用来对中小型民用船舶的船体有效功率进行估算。

Estimation of the effective power of a refrigerated transport ship

In order to solve the problem that the effective power of a refrigerated transport ship needs to be determined in advance when changing the pitch blade,the Froude number,square coefficient,Ayer coefficient and effective power of the hull are calculated by Ayer's method.This paper introduces the main parameters of the refrigerated ship,analyzes the principle,expression and Ayer's standard ship model parameters of Ayer's method,calculates the standard square coefficient and Ayer's coefficient of the refrigerated ship,and corrects the Ayer coefficient according to the difference between the square coefficient of the real ship,the width ratio of the ship,the longitudinal coordinate of the floating center and the length of the water line and the standard value,and estimates the effective power of the hull at different ship speeds according to the Ayer's method,and compares it with the results of the real ship test.The results show that the hull effective power estimated by Ayer's method is in good agreement with the actual ship test results,and can be used to estimate the hull effective power of small and medium civil ships.