【作者】 邓锐；

【导师】 黄德波；

【作者基本信息】 哈尔滨工程大学 ， 流体力学， 2010， 博士

【摘要】 二十一世纪是海洋的世纪,人类对于航运、海洋探索和开发的活动比以往的任何时期都更加广泛和深入,因此,对提高和改善船舶的水动力性能提出了更高的要求。中小型船舶在高航速情况下,船体周围及尾流场的水动力特性将直接影响到船舶的受力和主机所需的功率,在主尺度和主机功率给定的情况下,采取有效的措施改善船舶绕流场,使船舶在不同航速下航行时具有优良的阻力特性和运动性能,是船舶水动力学的热点之一。艉阻流板(stern interceptor)是近年出现的一种附体,它可以有效改变船体水动力性能,若对阻流板做合理的设计,可以通过改变其周围及船体艉后方的流场,提高船舶的快速性和操纵性,对于高速船型有很好的应用价值。阻流板相对于船体是尺度很小的附体,为了对带阻流板的船体的水动力进行模拟,需要一套有效的计算方案,以便准确反映安装阻流板前后流场的变化和效果。因此,首先采用商业计算流体力学软件Fluent对影响流场CFD计算的主要因素进行了计算探讨,针对网格划分方式、数值算法和湍流封闭模型给出适用于双体船及带有阻流板的双体船水动力性能数值计算的方案。经过大量的对比计算和关于适用性的研究,给出了适用的计算方案,针对其中的一些重要参数给出了建议的取值范围。利用提出的方案所得到的计算结果与试验结果进行了对比,验证了计算方案的正确性和适用性。阻流板和船体是相互干扰的,在对阻流板水动力机理的研究中的第一阶段,为了探讨阻流板邻近的水动力学机理,先做局部化处理:对船体进行了简化假设,以底部为平板的二维船体代替真实船体,对不考虑横向绕流和船体表面弯曲影响的阻流板水动力机理进行了研究。通过对不带阻流板以及带有不同高度阻流板的二维船体分别进行数值计算,分析阻流板的影响效果,进而详细计算对比了不带阻流板和带有阻流板的情况下,在阻流板的主要影响范围内,流场速度和压力的变化,捕捉流场的流动细节,探讨阻流板的水动力机理。在了解阻流板作用的水动力机理之后,尝试通过改变艉部构型以充分利用阻流板的作用来改善船体的水动力性能。随后,在上述研究的基础上,对三维船模带有阻流板前后的流场进行了模拟。首先计算了不带阻流板的双体船和带有不同高度阻流板的双体船的水动力性能,并将各种情况下的船体阻力计算结果与船模试验结果进行了比较,验证了计算的有效性,对双体船安装阻流板前后的水动力性能进行了比较,归纳上述研究,分析安装阻流板对船体作用的水动力机理,探讨阻流板对船体水动力性能的改善作用,研究了船型因素对阻流板作用的影响。通过计算研究,进一步明确了阻流板的水动力机理,了解了阻流板对双体船水动力性能的改善作用,并讨论了三维船体的横向绕流和表面弯曲对阻流板作用的影响。更多还原

【Abstract】 The 21th century is a century of ocean, human activities in ocean transportation, exploration and ocean energy exploitation appear much more intense and extensive, and which demand higher requirements to the improvement in ship hydrodynamic performances. When the medium and the smaller ships are travelling at high speed, the characteristics of flow field around and after stern affect the force acting on the ship and the power requirment. Under the conditions of that the main dimensions and the engine power are fixed, the method of improving the flow field around the ship, making the ship possess the best characteristics of resistance and motion, is one of the focuses. The stern interceptor is a kind of appendage newly developed in recent years, which, if well designed, is capable of improving the ship’s hydrodynamics performance, the speedity and the maneuverability, which has a very good prospect in high speed vessels.Comparing with the ship body, the height of a interceptor is much smaller, thus, an effective scheme is needed to simulate the flow field, in order to compare the flow field with and without interceptor. Therefore, the CFD software FLUENT is used ,some calculations and investigations on the main factors that affect flow field are taken, including the method of grid generation, numerical method and turbulence model, some suitable set are suggested for the numerical simulation of catamaran with and without interceptor. Comparison of the numerical results with the experimental data validates the proposed method and applicability of the suggested set.There is a interaction between the interceptor and the vessel, as the first stage of the investigation of the interceptor’s hydrodynamic mechanism, lowlization treatment is done near the stern, and simplifying first the real hull to a 2-D shiphull with flat bottom, ignoring the influence of transverse flow and curved form of the ship surface. Through the calculations of this 2-D ship with and without different height interceptors, the effect of the interceptor’s influence is determined, then, in the condition with and without interceptor, the changing of speed and pressure is compared in the area considerably affected by the interceptor, the mechanism of the interceptor is investigated. Some discussions of the effects of changing the stern form on the hydrodynamic characteristics are also included.Base on these research, simulation of the 3-D catamaran model with and without interceptor are taken, calculation and comparison of the catamaran’s hydrodynamic characteristics in the conditions with and without different height interceptors are included, and the comparisons of the numerical result of resistance and the experimental data show the effectiveness of the proposed calculation. The mechanism of the interceptor on the three dimensional ship is investigated; the effect of the interceptor to improve catamaran’s hydrodynamic characteristics is shown.更多还原