• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>International powered lift conference (IPLC 2008) >Large-eddy simulation of flow around a circulation control airfoil
【24h】

Large-eddy simulation of flow around a circulation control airfoil

机译：绕流控制翼型绕流的大涡模拟

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Large-eddy simulations are conducted for a circulation control airfoil at a chord-based Reynolds number of Re = u_∞c/v = 10~6 and two jet-momentum coefficients of C_μ = 0.03 and 0.1, chosen from Novak et al.~(1')s LDV measurement database. An incompressible unstructured solver is used with the dynamic subgrid-scale model. Instantaneous fields show that the flow near the leading edge is dominated by laminar to turbulent transition, and boundary-layer characteristics on the lower airfoil surface are very different in the two cases. Jet injection leads to a highly vortical and turbulent flow over the Coanda surface. Substantial deviations from the conventional law of the wall are found in the mean velocity profiles on the mid-to-trailing section of the upper airfoil surface as the jet is approached, which suggests that the inner layer as well as the outer one may have an explicit dependence on pressure gradient in this kind of flow. Meanwhile, over the Coanda surface, there exists a region where the mean flow development collapses very well in wall-jet similarity coordinates, indicating that a certain portion of the near-wall region still maintains wall jet characteristics. Considerable quantitative discrepancies from the experimental measurements remain for second-order turbulence statistics. Possible sources for these are the absence of a lower-surface transition trip in the simulations, smaller (by 7% and 9% for the two cases) values of C_μ in the simulation, and side-wall vortices due to a low wing aspect-ratio in the experiments. The first two of these will be eliminated in future work.
机译：从诺瓦克等人选择的基于弦的雷诺数Re =u_∞c/ v = 10〜6以及两个射流动量系数C_μ= 0.03和0.1的循环控制翼型进行大涡模拟。 （1's）LDV测量数据库。动态亚网格规模模型使用不可压缩的非结构化求解器。瞬时场表明，前缘附近的流动主要由层流向湍流过渡，两种情况下机翼下表面的边界层特征非常不同。射流喷射导致柯恩达表面上的高度涡旋和湍流。在接近射流时，在上翼型表面中部到尾部的平均速度剖面中发现了与常规壁规律的较大偏差，这表明内层和外层可能都具有明显依赖于这种流动中的压力梯度。同时，在柯恩达表面上，存在着一个区域，在该区域中，平均流动发展在壁流射流相似性坐标中非常好地塌陷，表明近壁区域的某些部分仍保持着壁流射流的特性。对于二阶湍流统计，仍存在来自实验测量值的大量定量差异。这些情况的可能来源是：在模拟中不存在下表面过渡行程，在模拟中C_μ值较小（两种情况分别减小7％和9％），以及由于机翼纵横比低而引起的侧壁涡旋。实验中的比率。其中的前两个将在以后的工作中删除。

著录项

  • 来源
  • 会议地点 London(GB);London(GB)
  • 作者

    Seonghyeon Hahn; rnKarim Shariff;

  • 作者单位

    Center for Turbulence Research, Stanford University, Stanford, CA 94305-3035, USA Electronic mail: shahn@stanford.edu;

    rnNASA Ames Research Center, Moffett Field, CA 94035, USA Electronic mail: Karim.R.Shariff@nasa.gov;

  • 会议组织
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 V212.131;
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号