摘要
采用雷诺平均的不可压缩流体控制方程和RNG k-ε湍流模型,对不同来流角、长宽比作用下村台周围的分离区及尾流区进行了数值模拟,得到了村台周围分离区及尾流区的时均流场分布。在此基础上,分析了不同长宽比和来流角对村台绕流下游尾流区长度、宽度和脱落涡频率的影响规律。结果表明:随着来流角的变化,村台绕流的分离区及尾流区特征受迎水面宽度的影响较大,特别是尾流区长度和宽度几乎与迎水面宽度成正比;随着长宽比的增加,村台周围分离区范围增大;村台尾流区的长度、宽度和脱落涡频率,在长宽比K<2.5时随长宽比K的增加略减小,在K=2.5附近达到最小值,然后随长宽比的增加而增大。
This paper applied Reynolds averaged incompressible fluid control equation and RNG k-8 turbulence model to carry out numerical simu- lation on the separation area and wake flow area around the platform under the effects of different incoming angles and length-width ratio, mean- while, the time-averaged flow distribution of the separation area and wake flow area around the platform were obtained, and accordingly analyzed the influencing rules of different length-width ratios and incoming angles on the length, width and vortex shedding frequency in downstream wake flow area of the flow field around the platform. The results show that： characteristics of the separation area and wake flow area around the platform are greatly influenced by the width of wet surface as the incoming angle changes, especially the width and length of wake flow area almost are directly proportional to the width of wet surface; as the length-width ratio K increases, the range of separation area around the platform increases as well ; the length, width and vortex shedding frequency of the platform wake flow area decrease slightly as K increases when K 〈 2.5, reach the minimum when K is about 2.5 and then increase as K increases.
出处
《人民黄河》
CAS
北大核心
2012年第8期113-116,共4页
Yellow River
关键词
村台绕流
分离区
尾流区
防护范围
黄河下游滩区
flow field around the village platform
separation area
wake flow area
defense range
floodplain in the downstream of the Yellow River
