The submerged hydrofoil has the capability to harness wave energy and convert it into thrust to work with the ship's power system. The current series of experiments investigated the interaction of a passive submerged hydrofoil with regular waves through a comparison of the generated horizontal forces. Springs provide the restoring force for the hydrofoil's heave/pitch motion, corresponding to heave spring and pitch spring. Maintaining a constant heave spring stiffness (490 N/m), subsequent statistical analysis summarized the force trends at different pitch stiffnesses (16–300 N/m) and suggested an optimal pitch spring stiffness in regular waves. A pulse-shaped force signal was observed and explained as a result of low pitch stiffness. Experiments with different spring setups revealed that the heave spring contributes to the harmonic force generated by the fully passive foil. Additionally, by varying wave conditions with limited wave amplitudes and frequencies, tests reproduced the variation of force signals over time and assessed their dependence on wave parameters.

中文翻译：

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用于船舶推进的波浪诱导扑翼的实验研究：升沉和纵摇刚度效应

水下水翼能够利用波浪能并将其转化为推力，与船舶动力系统配合使用。当前的一系列实验通过比较所产生的水平力来研究被动水下水翼与规则波浪的相互作用。弹簧为水翼的升沉/俯仰运动提供恢复力，对应于升沉弹簧和俯仰弹簧。在保持恒定的垂荡弹簧刚度（490 N/m）的情况下，随后的统计分析总结了不同纵摇刚度（16-300 N/m）下的力趋势，并提出了规则波浪中的最佳纵摇弹簧刚度。观察到脉冲形力信号并解释为低俯仰刚度的结果。使用不同弹簧设置的实验表明，升沉弹簧有助于完全被动箔产生的谐波力。此外，通过以有限的波幅和频率改变波浪条件，测试再现了力信号随时间的变化，并评估了它们对波浪参数的依赖性。