This paper applies load variation method to predict speed-power-rpm relationship along with propulsive performances in regular head waves, and to derive overload factors (ITTC, 2018). ‘Calm-water tests’ and ‘resistance test in waves’ are used. The modified overload factors are proposed taking non-linearity into consideration, and applied to the direct powering, and resistance and thrust identity method. These indirect methods are evaluated through comparing the speed-power-rpm relationships with those obtained from the resistance and self-propulsion tests in calm water and in waves. The objective ship is KVLCC2. The load variation method predicts well the speed-power-rpm relationship and propulsion performances in waves. The direct powering method with modified overload factors also predicts well. The resistance and thrust identity method with modified overload factor predicts with a little difference. The direct powering method with overload factors predicts with a relatively larger difference.

本文采用负载变化方法来预测常规头波中的速度-功率-转速关系以及推进性能，并得出过载系数（ITTC，2018）。使用“镇静水测试”和“波浪阻力测试”。提出了考虑非线性的修正过载系数，并将其应用于直接动力，阻力和推力识别方法。通过比较速度-功率-转速关系与在静水和波浪中的阻力和自推进试验获得的关系，可以评估这些间接方法。目标船是KVLCC2。载荷变化法很好地预测了波浪中的速度-功率-转速关系和推进性能。具有修正的过载系数的直接供电方法也可以很好地预测。修正了过载系数的阻力和推力识别方法之间的预测差异很小。具有过载系数的直接供电方法的预测差异较大。