【作者】 李佳；

【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】 随着海洋资源的深入开发与利用,载人潜器成为不可缺少的重要工具。载人潜器的用途广泛,设计形式多样,即使同一用途的载人潜器,其构型也各有不同。在载人潜器的初步设计阶段,需要对载人潜器的水动力性能进行计算,预报载人潜器的有效功率,从而为载人潜器配置合适的动力装置提供依据。潜器的节能问题尤为重要,对于初步设计的载人潜器,在满足使用要求的前提下需要对其外形进行阻力性能优化,从而节省能耗。为了能够预报载人潜器的有效功率,首先对载人潜器外形进行简化,略去次要附体并对主要附体的构型用相似几何体替代,然后用CFD方法对简化模型进行数值计算,得到载人潜器模型的阻力系数。引入形状简化因子,将阻力系数的计算值与试验值进行比较,从而得到形状简化因子的数值。用CFD方法对简化的载人潜器实体进行数值计算,将形状简化因子应用于载人潜器实体的阻力系数,最终得到载人潜器的有效功率。为了对载人潜器的外形进行阻力性能优化,‘需要对载人潜器的数值模拟方法进行研究,得到有效的计算方法,并对载人潜器的阻力性能进行分析,从而为载人潜器的外形优化提供前提条件。为此,以载人潜器的主体和主要附体为研究对象,对其流场进行结构化网格离散,讨论不同湍流模型以及入口湍流强度的不同设置对阻力计算结果的影响,确定对载人潜器实施型值优化时的数值计算方法。载人潜器构型复杂,并且附体较多,在水下运动姿态多样,因而有必要对载人潜器不同运动姿态下的水动力性能做试验研究。为了在船模拖曳水池中完成载人潜器不同运行姿态的阻力试验,需要加工制作载人潜器的缩尺模型,并设计运动姿态调整方案。为了完成载人潜器模型不同艏向角和垂直上升及下潜航行时的阻力试验,专门设计加工了一套可调艏向角及浸深的拖带装置。对不同艏向角和航速分别进行了拖带装置携带和不携带潜器模型的阻力测量,从而得到了潜器正浮状态不同艏向角航行时的总阻力系数。根据雷诺数相等原则进行潜器模型与实体的阻力换算,并加入换算补贴系数得到潜器实体的总阻力系数,最终得出潜器实体不同艏向角航行时的阻力及有效功率。考虑载人潜器主体和主要附体中电池舱的优化问题,将三维几何体的阻力性能优化转化为二维几何体的外形优化。用多岛遗传算法对二维几何体的阻力数值计算进行一体化优化,并将优化结果应用于三维几何体的型值。经过不同方案的探索,最终得出在满足工程需要的前提下适于该载人潜器的优化外形,优化潜器的阻力比原型减少13%左右,单位体积载人潜器模型阻力的优化收效大于20%。更多还原

【Abstract】 Manned submersibles are very important vehicles for exploring and making use of ocean resource. The use of manned submersibles is wide spread, and the designs of them have various kinds of forms for different purpose. The form of manned submersibles is even different for the same purpose. It needs calculation for hydrodynamic performances and prediction of effective power of manned submersibles in preliminary design. Accordingly, it offers the base of fixing power equipments of manned submersibles. It needs form optimization for drag reduction in order to save power for manned submersibles of preliminary design in precondition of satifying use demand.In this dissertation, in order to predict the effective power of a manned submersible, the submersible model is predigested into a like type of computational model, which major appendages are predigested to somewhat simpler forms, and some small appendages are ignored. The flow field of the computational model is numerically simulated using CFD method, and the drag coefficient of the computational submersible model is obtained. The computational and tested results of drag coefficient are compared. A form factor is introduced by comparing the computational and tested results. The simplified form for the manned submersible is calculated with CFD method, and the form factor is applied in the predictions of the drag and required power of the manned submersible.To optimize the form of the manned submersible for drag reduction, it is necessary to study for finding an effective numerical simulation method, and analyze thereby the drag performance of the manned submersible. A workable computational method is obtained, and it is used as a basis for form optimization of the manned submersible. In searching that method, the drag calculations of the main body and major appendages of the manned submersible are investigated. The flow field around the bodies is discretized into structured grids, and the influence of different turbulence models and turbulence intensity of inlet on drag results is discussed. The numerical simulation method is obtained for conducting form optimization of the manned submersible.The form of the manned submersible is complex, with many appendages, and it will move with various attitudes. It is necessary to do tested research for hydrodamic performances of the manned submersible moving in different attitudes. To conduct model tests in a towing tank, a scaled model of the manned submersible is made, and a test program is worked out to cover the moving attitudes as required by the project. To obtain the drags for driving the manned submersible model at different yaw angles and in the cases of both ascending and descending, a towing device is dedicatedly made for the tests, making possible to easily adjust both the yaw angle and submergence of the tested model. From measured total drags of both the submersible model with the towing swords and the towing swords without the model at different speeds and yaw angles, drag data reduction is made following the dynamic similitude with equivalent Reynolds Number. The total drag coefficients, and thus the effective power of the corresponding full hull in each case are obtained.The main body and battery pods of the manned submersible are considered for optimization. Form optimizations of 2-D bodies are conduceted instead of considering 3-D forms. 2-D forms are optimized with multi-island genetic algorithm for drag reduction, and the optimum results are applied to the 3-D form. After comparing different optimized forms, an optimum form of the manned submersible is obtained, which is shown, by calculation, about 13% drag reduction for the manned submersible, and more than 20% drag reduction for per unit volume.更多还原