Characteristics of unsteady turbulent boundary layr with separated vortices

分离涡非定常湍流边界层特征

• 批准号: 08455476
• 负责人: SUZUKI Toshio
• 金额: $ 4.93万
• 依托单位: Osaka University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08455476/
• 关键词: large roughness; inertia force in waves; viscous force in waves; area density of roughness; effective projected diameter; unsteady motions; Ship model wake; longitudinal vortices; 船尾境界層; 慣性力

Characteristics of unsteady turbulent boundary layr with separated vortices were investigated. Three kinds of flow field were measured experimentally.1. Flow behind large roughness in thin boundary layr.2. Flow around a circular cylinder in waves.3. Flow behind two kinds of ship stern, fine ship model and full ship model.Obtained results are as follows ;1. When the area density of roughness exceed 15% of surface of a cylinder effective diameter of the cylinder with roughness close to the reference diameter Dr=D+2K (D : diameter of cylinder, K : roughness height).2. Roating flow are observed when a circular cylinder was arranged under the wave surface and settled parallel to the crest line.3. Analyzed inertia force and viscous force show different characteristics in wave or oscillating motions, but non-dimensional coefficients are almost the same values.4. There are some correlation between variation of 3-d longitudinal vortices and wake distributions of fine ship model at low frequency harmonics.5. Stronger longitudinal vortices make the wake distribution behind a full hull form model ship stable.

研究了分离涡非定常湍流边界层的特征。对三种流场进行了实验测量： 1．薄边界层大粗糙度后的流动。2．以波浪形式绕圆柱体流动。3．对两种船尾、精船模型和整船模型进行了流后处理。得到的结果如下： 1．当粗糙度面积密度超过圆柱体表面15%时，粗糙度接近基准直径的圆柱体有效直径Dr=D+2K（D：圆柱体直径，K：粗糙度高度）。2．当圆柱体置于波面下方并平行于波峰线放置时，可观察到旋转流。 3．分析的惯性力和粘性力在波浪或振荡运动中表现出不同的特性，但无量纲系数几乎是相同的值。 4．精细船模低频谐波下三维纵向涡的变化与尾流分布存在一定的相关性。 5．更强的纵向涡流使全船体模型船后面的尾流分布更加稳定。

项目成果

Hiroyoshi SUZUKI,Toshio SUZUKI,Satoshi MIYAZAKI: "Turbulence Measurements in a Stern Flow Field of a Ship Model -Series 60, CB=0.6-" Journal of the Kansai Society of Naval Architects, Japan. No.227. 29-40 (1997)

Hiroyoshi SUZUKI、Toshio SUZUKI、Satoshi MIYAZAKI：“船舶模型尾流场中的湍流测量 - 系列 60，CB=0.6-”日本关西造船学会杂志。

Hiroyoshi SUZUKI,Satoshi MIYAZAKI,Toshio SUZUKI,Kiyoshige MATSUMURA: "Turbulence in Stern Flow Fields around a Oblique Ship Model" Proceedings of the Kansai Society of Naval Architects, Japan. Vol.10 (in print). (1998)

Hiroyoshi SUZUKI、Satoshi MIYAZAKI、Toshio SUZUKI、Kiyoshige MATSUMURA​​：“斜船模型周围船尾流场中的湍流”日本关西造船学会论文集。

鈴木 博善: "模型船船尾まわりの乱動計測-シリーズ60.CB=0.6-" 関西造船協会誌. 227. 29-40 (1997)

Hiroyoshi Suzuki：“模型船尾部湍流的测量 - Series 60.CB=0.6-”关西造船协会杂志 227. 29-40 (1997)。

鈴木博善: "模型船船尾まわりの乱動計測-シリーズ60,CB=0.6-" 関西造船協会誌. 227. 29-40 (1997)

Hiroyoshi Suzuki：“模型船尾部湍流的测量 - Series 60，CB=0.6-”关西造船协会杂志 227. 29-40 (1997)。

鈴木博善: "斜航時における船尾まわりの乱動計測" 関西造船協会誌. 230. (1998)

Hiroyoshi Suzuki：“倾斜航行时船尾周围湍流的测量”关西造船协会杂志 230。（1998）