【作者】 綦志刚；

【导师】 金鸿章；

【作者基本信息】 哈尔滨工程大学 ， 控制理论与控制工程， 2008， 博士

【摘要】 船舶在低航速或零航速作业时,减摇水舱是用来减小船舶横摇的最主要的减摇设备。但是减摇水舱本身的减摇能力有限,而且只是在谐摇频率的情况下,才能达到最好的减摇效果,在某些情况下甚至会出现增摇的现象。而传统的减摇鳍一般只能在中高航速下才能有效地进行减摇,这是由传统减摇鳍减摇机理决定的。传统减摇鳍的升力同船舶的航行速度的平方成正比,因此船舶的航行速度越高,产生的升力也相对较大。随着减摇技术的发展,一种新的减摇技术可以使用减摇鳍在零航速下进行船舶减摇,但其减摇理论仍处在发展阶段。论文来源于国家自然科学基金项“零速下船舶仿生减摇鳍升力机理的研究(50575048)”。主要研究内容是减摇鳍在零航速下摆动时的运动规律及其升力模型的建立。论文首先对零航速减摇装置做了综述,阐述了减摇鳍在零航速下工作的减摇原理。论文给出了单翼纵向拍动型、单翼横向拍动型、单翼纵向拍动耦合升沉运动和双翼纵向拍动型等几种类型的零航速减摇鳍,并对其工作原理进行了分析。单翼零航速减摇鳍升力模型的研究是减摇鳍能否在零航速下用于船舶减摇的关键问题。通过对两种不同工作方式的零航速减摇鳍升力模型进行理论研究,根据单翼Weis-Fogh机构势流理论对单翼横向拍动的减摇鳍进行了升力建模,得到的升力模型基本上反映了鳍拍动时升力产生的情况。同时对单翼纵向拍动的减摇鳍进行了升力模型建模,根据鱼尾摆动将鳍上所受到的力分为法向力、附加质量力和涡的影响力进行研究,建立相应的简化模型。最后使用Fluent计算流体力学软件对单翼纵向拍动减摇鳍进行了数值模拟,从得到的升力曲线上可以看出前面建立的升力模型基本上可以反映鳍摆动时产生升力的规律。双翼零航速减摇鳍升力模型的建立是基于Weis-Fogh机构流体动力学理论。基于势流理论得出的升力模型由于对一些参数进行了假设,其升力模型并没有很好的反应出鳍上的升力变化情况。因此进一步研究和建立了基于点涡理论的双翼零航速减摇鳍升力模型。从其升力曲线的对比上可以看出,基于点涡理论的升力模型可以更好的反映鳍上产生升力的情况。最后建立了船舶-单翼零航速减摇鳍和船舶-双翼零航速减摇鳍模型。据实船参数对船舶-单翼零航速减摇鳍模型和船舶-双翼零航速减摇鳍模型在不同海况下的船舶横摇进行了仿真,从仿真结果上可以看出在低海情的时候单翼零航速减摇鳍的减摇效果可以达到55%以上,双翼零航速减摇鳍的减摇效果在50%左右。更多还原

【Abstract】 Anti-roll tank is main anti-roll system to reduce ship roll when ship is at zero speed or low speed. But anti-roll capacity of anti-roll tank is limit, and anti-roll tank got the best anti-roll effectiveness when its resonance frequency is similar as ship roll frequency, it will increase ship roll in some frequency. Traditional fin stabilizer only can reduce ship roll when ship speed is medium or high, it is decided by its anti-roll theory. Lift generated from traditional fin stabilizer is proportional to the square of velocity of ship, so lift is increased when ship speed is high. A new kind of anti-roll technology which fin stabilizer is used to reduce ship roll at zero speed came out as anti-roll technology developed, anti-roll theory is still developing now.The dissertation is based on project supported by national science foundation of China: research on lift theory of ship bionic roll stabilization at zero speed(50 575048).Main research area is about rotating way and lift model of fin stabilizer when ship is at zero speed .First anti-roll systems are introduced, then anti-roll theory of fin stabilizer at zero speed is narrated. Four types of fin stabilizer at zero speed is proposed as single fin stabilizer pitching at zero speed, single fin stabilizers rolling at zero speed, single fin stabilizer pitch and heave at zero speed and double-wing fin stabilizers flapping at zero speed, and their working process are analyzed.Researching on lift model of fin stabilizer at zero speed is a key problem to decide whether fin stabilizer can be used to reduce ship roll at zero speed. Two different types of single fin stabilizer’s working principles and their lift models have been studied. Lift model of single fin stabilizers rolling at zero speed was built based on potential theory of single Weis-Fogh mechanism, and lift model proposed can basically give the changing of lift on fin stabilizer as fin stabilizer is rotating. Lift model of single fin stabilizers pitching at zero speed was built based on tail fin swaying theory of fish, force on fin is divided three part: normal force, added mass force and influence force of vortex and their simple model is built. Numerical simulation of single pitching fin stabilizer is done by using a CFD software (Fluent), the lift curve of fin stabilizer got from Fluent is compared with the simulation curve from lift model, the lift model can simulate the force generated from fin stabilizer basically as fin stabilizer rotates.Lift model of double-wing fin stabilizer flapping at zero speed was built base on hydrodynamic theory of Weis-Fogh mechanism. Some parameters were assumed in potential theory, lift model built based on potential theory can not reflect real lift on fin stabilizer. So lift model base on vortex theory was built. Lift model base on vortex theory can simulate lift better than lift model base on potential theory.Finally, ship-single fin stabilizer and ship-double-wing fin stabilizer models were built. Ship-single fin stabilizer model and ship-double-wing fin stabilizers were used to simulate ship roll base on real ship parameters under different sea conditions, single fin stabilizer at zero speed can reduce ship roll well under low sea condition and anti-roll effectiveness is more than 55% from simulation results, the anti-roll effectiveness of double-wing fin stabilizers was about 50%.更多还原