排序方式: 共有58条查询结果,搜索用时 703 毫秒
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研究了零航速时仿生减摇鳍产生升力的数学模型,讨论了Weis-Fogh 机构如何旋转才能产生船舶减摇所需要的指定升力,其基础为Weis-Fogh 机构理论.首先把问题转化为求解微分方程问题,依据吕卡提方程,给出模型周期解的存在性和稳定性条件;然后采用单步Runge-Kutta方法求出模型的数值解,并分析数值解的全局误差;最后给出保证数值解稳定的条件,并用相应的数值试验予以验证. 相似文献
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Research on roll stabilization for ships at anchor 总被引:2,自引:0,他引:2
With the increasing importance of ocean exploitation, providing anti-rolling stability for ships at anchor has become more and more important. The lift-generation theory of traditional fin stabilizers is based on incoming flow velocity, which is not suitable for explaining lift generated at anchor. We analyzed non-steady flows, with forces on fin stabilizers generated by non-incoming flow velocity conditions, and gave a new lift-generation model. The correctness of the model was proven by comparing experimental results of fin stabilizer motion under non-incoming velocity conditions from the fluid computation software with that from the emulator of the lift-generation model. Finally, the model was used in an anti-rolling system on a ship and the reduction of roll was much better than what could be achieved by passive anti-rolling tanks. 相似文献
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Conventional PID controllers are widely used in fin stabilizer control systems, but they have time-variations, nonlinearity, and uncertainty influencing their control effects. A lift feedback fuzzy-PID control method was developed to better deal with these problems, and this lift feedback fin stabilizer system was simulated under different sea condition. Test results showed the system has better anti-rolling performance than traditional fin-angle PID control systems. 相似文献
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被动可控式U型减摇水舱利用气阀开关控制水舱内液体运动,使之与船舶横摇运动保持π/2相位差。文章针对在随机海浪下水舱被动控制中存在的问题,提出了由两个被动可控式减摇水舱组成的被动可控式双水舱减摇系统,文中对双水舱系统的数学模型及系统设计方法进行了研究,并提出利用不同的船舶横摇信号分别控制两个水舱内液体流动的被控式PD控制策略。以高速滚装船为例,对双水舱系统进行了计算机仿真,仿真结果表明被动可控式双水舱系统在更宽的海浪干扰频率范围内具有更好的减摇效果。 相似文献
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