﻿ 大气边界层对SFS2空气尾流特性的影响
 舰船科学技术  2018, Vol. 40 Issue (8): 37-40 PDF

Influence of ABL on SFS2 ship airwake
WANG Jin-ling, JIANG Guang-wen, YANG Miao-sheng
Systems Engineering Research Institute, Beijing 100036, China
Abstract: In order to research the influence of atmospheric boundary layer (ABL) existing above the ocean surface on the ship airwake, the typical simplified frigate shape SFS2 ship airwake in uniform in?ow condition and two different ABL conditions are simulated using Ansys Fluent. The research concluded that the speed gradient in the ABL decreases flow kinetic energy of entrance, while the turbulence kinetic energy increases the energy input, so the velocity magnitude predicted with both velocity gradient and the turbulence characteristic is between that with uniform inflow and single velocity gradient. The results demonstrate that ABL exerts an unneglected effect on the ship airwake.
Key words: atmospheric boundary layer (ABL)     ship airwake     SFS2     CFD     turbulence
0 引　言

1 仿真方法 1.1 湍流模型

1.2 几何模型与网格划分

 图 1 SFS2几何模型 Fig. 1 Simple frigate shape (SFS) dimensions

 图 2 SFS2网格分布 Fig. 2 Structured mesh for SFS2
1.3 边界条件

 $U\left( z \right) = {U_{ref}}{\left( {\frac{z}{{{z_{ref}}}}} \right)^n}{\text{，}}$ (1)

 ${I_i}\left( z \right) = \frac{{{\sigma _i}\left( z \right)}}{{U\left( z \right)}}{\text{，}}$ (2)

2 仿真方法的验证

 图 3 SFS2风洞实验模型 Fig. 3 SFS2 model in the test section of the wind tunnel

 图 4 SFS2 CFD与实验结果对比 Fig. 4 Comparison of CFD and experimental for SFS2
3 大气边界层对SFS2空气流场特性的影响分析

 图 5 0°风向角时不同边界条件下速度对比 Fig. 5 Comparison of velocity of headwind in different boundary conditions

 图 6 45°风向角时不同边界条件下速度对比 Fig. 6 Comparison of velocity of green 45° in different boundary conditions

 图 7 0°风向角时不同边界条件下SFS2截面速度云图对比 Fig. 7 Comparison of x, y-component velocity contours for different slices of SFS2 with headwind

4 结　语

1）基于k-ε模型和壁面函数的CFD仿真方法可以用于预测舰船空气尾流；

2）大气边界层条件中的速度梯度会减小气流流动动能的输入；

3）湍流特性中湍动能会增加入口能量的输入；

4）湍流特性会减弱固体壁面至大气边界层厚度位置之间的动量传递；

5）大气边界层条件中速度梯度与湍流特性对流场产生的影响不可忽略。

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