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Mono-wave-piercing boats adopt a tumblehome and wave-piercing design which is becoming popular among military vessels and yachts. Published studies on mono-wave-piercing boats mostly focused on motions and stability in waves, or were conducted at low speed. A new high speed mono-wave-piercing boat is developed in this study and model tests have been finished in order to reveal more sailing characters of mono-wave-piercing boats. Special attention is paid to the sailing characters of mono-wave-piercing boats at speed. Model tests include resistance tests in calm water and seakeeping performance tests in regular waves. Available model test results give an insight in the way how the mono-wave-piercing boat runs in calm water and regular waves at speed and are valuable reference for similar and derived design. 相似文献
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An immersed body boundary method is adopted to track the motions of a towing cylinder, and a homogenous multiphase Eulerian-Eulerian fluid approach is used to capture the free surface. The Reynolds average Navier-Stockes (RANS) solver is applied to all gird nodes to deal with different velocities of the nodes that are in the body boundary, near the boundary and out of the boundary and their effect on the fluid. The towing cylinder resistance at different submerged depths in the tank is presented. The simulation results are compared with the experimental data, and the method is verified and validated. Finally, the hydrodynamic characters of the cylinder are discussed further. The numerical and experimental results show that at high speeds, the deeper the cylinder submerges, the lower resistance it suffers. The resistance coefficient trough is obtained at Froude number in the range of 0.3 < F r < 0.4. These phenomena can provide some suggestions on the small waterplane area twin hull (SWATH) design. 相似文献
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传统的设计螺旋方法由于割裂了学科间耦合,得到的设计往往是满足设计要求的设计而不是最优的设计.多学科设计优化(MDO)方法正是一种能得到最优设计的新设计方法,MDO目前被广泛应用于复杂工程系统的设计中.文中对多学科设计优化的理论进行了简要综述,在此基础上为了演示MDO方法应用于舰船设计,采用iSIGHT对国外的CGX巡洋舰概念设计的13个模块进行了集成,建立了MDO模型并优化,得到了较好的优化解.在此基础上采用神经网络重新建立了该MDO模型,将优化结果和原MDO模型优化结果进行了比较. 相似文献
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相对于一级深拖系统,二级深拖系统具有良好升沉补偿功能,并且较易对拖体进行定深或定高控制。在实际工作中,母船经常需要根据探测情进行回转机动。为了研究母船回转过程中拖体运动规律和拖缆构形的变化情况,采用凝集质量法建立了二级深拖系统的数学模型,计算分析了母船不同回转参数下拖体运动状态的变化规律,得到了拖缆的瞬态和稳态构形图。仿真结果表明,在360°稳态回转和360°单圈回转条件下,母船回转半径、拖曳速度均对一级拖体和二级拖体的深度变化以及稳态特性有显著影响。母船小半径大速度回转时,两级拖体的回转半径和深度变化较大,应予以特别关注。 相似文献
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以三体船的操纵性能预报为背景,基于势流理论的三维面元法,对三体船的斜拖运动进行数值模拟,并求得相应的水动力系数。将传统的运用于机翼升力计算的涡环栅格法(VLM)运用于三体船斜拖运动的数值模拟,船体表面被离散成四边形的网格,网格及尾涡面上布置一个涡环,利用船体表面不可穿透条件以及尾缘处的库塔条件对各单元涡强进行求解,求得各个分布点压强以及船体表面压力分布,并根据压力分布积分求得在不同漂角下三体船舶所受的横向力以及转首力矩。最终由计算结果,求得与漂角相关的水动力系数,并与软件计算结果进行对比分析。 相似文献
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