基于转捩SST模型的钝尾缘水翼绕流数值计算与分析

发布时间：2018-01-28 00:10

  本文关键词： 水翼 边界层转捩 γ-Reθt转捩模型 尾涡脱落　出处：《水利学报》2017年08期 　论文类型：期刊论文

【摘要】：边界层转捩是影响水翼绕流水动力学特性的关键因素之一。为了探究γ-Reθt转捩模型在低湍流度来流下水翼边界层转捩及尾涡脱落预测中的适用性,本文基于耦合γ-Reθt转捩模型和SST k-ω模型的转换SST模型,对0°攻角的NACA0009钝尾缘水翼绕流进行了数值计算。分析了转捩SST模型对网格尺度的敏感性,预测了边界层和尾迹区流场及不同雷诺数下水翼尾涡脱落特征,并与实验数据和SST k-ω模型计算结果进行了对比。结果表明:随近壁面第一层网格尺度y+的增大,水翼边界层转捩位置沿流向后移,最大y+值小于1时,预测的转捩位置趋于一致;与SST k-ω模型相比,转捩SST模型可以求解层流边界层,避免了在边界层和尾迹区对涡黏系数的过高预测,得到的边界层厚度和水翼尾迹区流动参数与实验结果更为接近;转捩SST模型可以较准确预测水翼尾涡脱落频率随雷诺数增大而增加的变化趋势,水翼尾涡脱落频率预测值与实验结果的最大相对误差为6.2%。
[Abstract]:Boundary layer transition is one of the key factors affecting the dynamic characteristics of hydrofoil around income. In order to explore the applicability of 纬 -Re 胃 t transition model in prediction of hydrofoil boundary layer transition and wake shedding under low turbulence. Based on the coupled 纬 -Re 胃 t transition model and the SST k- 蠅 model, the transformed SST model is presented in this paper. The flow around the flank of NACA0009 with 0 掳angle of attack is numerically calculated, and the sensitivity of transition SST model to grid scale is analyzed. The flow field in the boundary layer and wake region and the wake shedding characteristics of hydrofoil under different Reynolds numbers are predicted. The results are compared with the experimental data and the SST k- 蠅 model. The results show that with the increase of the scale y of the first layer near the wall, the transition position of the hydrofoil boundary layer moves backward along the flow direction. When the maximum y value is less than 1:00, the predicted transition position tends to be consistent. Compared with the SST k- 蠅 model, the transition SST model can solve laminar boundary layer and avoid the excessive prediction of vortex viscosity coefficient in the boundary layer and wake region. The thickness of the boundary layer and the flow parameters of the hydrofoil wake are closer to the experimental results. The transition SST model can accurately predict the variation trend of wake shedding frequency with the increase of Reynolds number. The maximum relative error between the predicted value and the experimental results is 6.2.
【作者单位】： 中国农业大学水利土木工程学院;北京市供水管网系统安全与节能工程技术研究中心;
【基金】：国家自然科学基金项目(51409147) 中央高校基本科研业务费专项资金项目(2015SYL001)
【分类号】：TV136
【正文快照】： 2.北京市供水管网系统安全与节能工程技术研究中心,北京100083)1研究背景水力机械叶片表面的流动转捩,直接影响叶片升阻力、尾涡脱落频率等宏观流动特征及机组的水力性能。水翼是水力机械叶片的简化模型,在低湍流度自由来流条件下,光滑水翼壁面边界层存在从层流到湍流的自然转，

本文编号：1469209