半约束下小水线面三体船阻力特性仿真研究

Numerical Study on Resistance of Trimaran Small Waterplane Area Center Hull under Half Constrained Condition

基于数值仿真方法研究了一种高性能水面船型——小水线面三体船的垂荡、纵摇运动及侧体位置对其所受阻力的影响。采用RANS方程和SST k-ω湍流模型,对其在不同约束条件下的水动力性能进行数值仿真,讨论不同约束条件对仿真结果的影响。在半约束条件下数值模拟其不同侧体位置的水动力性能,研究侧体布局对其阻力的影响。结果显示,半约束时三体船的模拟阻力较全约束时在低、中、高航速下分别增加了6.8%,4.5%和7.5%;不同侧体布局时,三体船的总阻力差异主要来自于压差阻力(变化率为27.7%)。研究表明论文使用的CFD模拟方法是有效的,同时释放垂荡和纵摇自由度时小水线面三体船的总阻力模拟结果较全约束时有所下降;高航速下(Fr=0.5),侧体纵向、横向相对位置的改变会形成不同性质的兴波干扰,显著影响船体阻力。

The influence of heave,pitch motion,and side body position on the resistance of a high performance surface ship type,Trimaran Small Waterplane Area Center Hull(Tri-swach),is investigated using the numerical simulation method.Its hydrodynamic performance under different constraint conditions is numerically simulated using RANS equation and turbulence model,and the influence of different constraint conditions on the simulation results is discussed.Its hydrodynamic performance at different side body positions is numerically simulated under semi-constraint conditions,and the influence of side body layout on its resistance is studied.Compared with the simulated resistance value of the trimaran under full restraint state,the resistance in the semi-constrained state increases by 6.8%,4.5%,and 7.5%at low,medium,and high speeds respectively;the difference in the total resistance of the trimaran with different side hulls layouts is mainly Wave resistance(change amplitude 27.7%).The study shows that the CFD simulation method used in this paper is effective;the simulation results of the total resistance of the small waterplane area trimaran when the degrees of freedom of heave and pitch are released at the same time are lower than that of the full constraint;at high speeds(Fr=0.5),Variations in the relative positions of the side hulls in the longitudinal and transverse directions will cause wave-making interference of different natures,which will significantly affect the hull resistance.