• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Direct numerical simulation of shockwave and turbulent boundary layer interactions.
【24h】

Direct numerical simulation of shockwave and turbulent boundary layer interactions.

机译：冲击波与湍流边界层相互作用的直接数值模拟。

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

Direct numerical simulations (DNS) of a shockwave/turbulent boundary layer interaction (STBLI) at Mach number 3 and Reynolds number based on the momentum thickness of 2300 are performed. A 4th-order accurate, bandwidth-optimized weighted-essentially-non-oscillatory (WENO) scheme is used and the method is found to be too dissipative for the STBLI simulation due to the over-adaptation properties of this original WENO scheme. In turn, a relative limiter is introduced to mitigate the problem. Tests on the Shu-Osher problem show that the modified WENO scheme decreases the numerical dissipation significantly. By utilizing a combination of the relative limiter and the absolute limiter described by Jiang & Shu [32], the DNS results are improved further. The DNS data agree well with the reference experiments of Bookey et al. [10] in the size of the separation bubble, the separation and reattachment point, the mean wall-pressure distribution, and the velocity profiles both upstream and downstream of the interaction region.; The DNS data show that velocity profiles change dramatically along the streamwise direction. Downstream of the interaction, the velocity profiles show a characteristic "dip" in the logarithmic region, as shown by the experiments of Smits & Muck [66] at much higher Reynolds number. In the separation region, the velocity profiles are found to resemble those of a laminar flow, yet the flow does not fully relaminarize. The mass-flux turbulence intensity is amplified by a factor of about 5 throughout the interaction, which is consistent with that found in higher Reynolds experiments of Selig et al. [52]. All Reynolds stress components are greatly amplified by the interaction. Assuming that the ow is still two dimensional downstream of the interaction, the components rhou'u', rhov'v', rho w'w', and rho u'w' are amplified by factors of 6, 6, 12, and 24, respectively, where u is the streamwise and w is the wall-normal velocity. However, analyses of the turbulence structure show that the ow is not uniform in the spanwise direction downstream of the interaction. A pair of counter-rotating vortices is observed in streamwise-wall-normal planes in the mean ow downstream of the ramp corner. Taking the three-dimensionality into account, the amplification factors of the Reynolds stresses are greatly decreased. The component rhou'w' is amplified by a factor of about 10, which is comparable to that found in the experiments of Smits & Muck [66]. Strong Reynolds analogy (SRA) relations are also studied using the DNS data. The SRA is found to hold in the incoming boundary layer of the DNS. However, inside and downstream of the interaction region, the SRA relations are not satisfied.; From the DNS analyses, the shock motion is characterized by a low frequency component (of order 0.01Uinfinity/delta). In addition, the motion of the shock is found to have two aspects: a spanwise wrinkling motion and a streamwise oscillatory motion. The spanwise wrinkling is observed to be a local feature with high frequencies (of order Uinfinity /delta). Two-point correlations reveal that the spanwise wrinkling is closely related to the low momentum motions in the incoming boundary layer as they convect through the shock. The low frequency shock motion is found to be a streamwise oscillation motion. Conditional statistics show that there is no significant difference in the mean properties of the incoming boundary layer when the shock is at an upstream or downstream location. However, analyses of the unsteadiness of the separation bubble reveal that the low frequency shock motion is driven by the downstream flow.
机译：基于动量厚度2300进行了马赫数3和雷诺数的冲击波/湍流边界层相互作用（STBLI）的直接数值模拟（DNS）。使用了四阶准确，带宽优化的加权基本非振荡（WENO）方案，由于该原始WENO方案的过度自适应特性，该方法对于STBLI仿真而言过于耗散。反过来，引入了一个相对限制器来减轻该问题。对Shu-Osher问题的测试表明，改进的WENO方案显着降低了数值耗散。通过使用Jiang＆Shu [32]所描述的相对限制器和绝对限制器的组合，可以进一步改善DNS结果。 DNS数据与Bookey等人的参考实验非常吻合。 [10]在分离气泡的大小，分离和重新附着点，平均壁压分布以及相互作用区域上游和下游的速度分布方面。 DNS数据显示，速度剖面沿流向急剧变化。在相互作用的下游，速度分布在对数区域显示出特征性的“倾角”，如Smits＆Muck [66]在更高的雷诺数下的实验所示。在分离区域中，发现速度分布类似于层流的速度分布，但该流并未完全重新分层。在整个相互作用中，质量通量湍流强度被放大了大约5倍，这与Selig等人在更高的雷诺兹实验中发现的一致。 [52]。相互作用使所有雷诺应力分量大大放大。假设ow仍然是交互作用的二维下游，则分量rhou'u'，rhov'v'，rho w'w'和rho u'w'被放大了6、6、12和24倍，其中u是沿流方向，w是壁法向速度。但是，对湍流结构的分析表明，在相互作用下游，翼展方向上的流动不均匀。在坡道拐角下游的平均流中，在顺流壁法线平面中观察到一对反向旋转的涡流。考虑到三维，雷诺应力的放大因子大大降低。 rhou'w'分量被放大了大约10倍，这与Smits＆Muck [66]实验中发现的相当。还使用DNS数据研究了强雷诺类比（SRA）关系。发现SRA保留在DNS的传入边界层中。但是，在交互区域的内部和下游，不能满足SRA关系。根据DNS分析，震动运动的特征在于低频分量（0.01Uinfinity /δ量级）。另外，发现冲击的运动具有两个方面：翼展方向的起皱运动和流方向的振动运动。观察到翼展方向的起皱是高频（Uinfinity /δ量级）的局部特征。两点相关性表明，跨度起皱与进入边界层中的低动量运动通过冲击对流密切相关。发现低频冲击运动是沿流的振荡运动。条件统计表明，当冲击位于上游或下游位置时，传入边界层的平均特性没有显着差异。然而，对分离气泡的不稳定性的分析表明，低频冲击运动是由下游流动驱动的。

著录项

  • 作者

    Wu, Minwei.;

  • 作者单位

    Princeton University.;

  • 授予单位 Princeton University.;
  • 学科 Engineering Aerospace.
  • 学位 Ph.D.
  • 年度 2007
  • 页码 164 p.
  • 总页数 164
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 航空、航天技术的研究与探索;
  • 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