方案摘要
方案下载应用领域 | 航空航天 |
检测样本 | 航空 |
检测项目 | |
参考标准 | 暂无 |
采用2台Litron激光器。三台LX Imager 16M相机。构成2DPIV测量系统。采用拼接方式测量大视场。利用2DPIV快照结果求得压力场。
In this study, we quantify the accuracy of a simple pressure estimation method from 2D snapshot PIV in attached and separated flows. Particle image velocimetry (PIV) offers the possibility to acquire a field of pressure instead of point measurements. Multiple methods may be used to obtain pressure from PIV measurements, however, the current state-of-the-art
requires expensive equipment and data processing. As an alternative, we aim to quantify the efficacy of estimating instantaneous pressure from snapshot (non-time resolved) two-dimensional planar PIV (the simplest type of PIV available). To make up for the loss of temporal information, we rely on Taylor’s hypothesis (TH) to replace temporal information with
spatial gradients. Application of our approach to high-resolution 2D velocity data of a turbulent boundary layer flow over ribs shows moderate to good agreement with reference pressure measurements in average and fluctuations. To assess the performance of the 2D TH method beyond average and fluctuation statistics, we acquired a time-resolved measurement of
the same flow and determined temporal correlation values of the pressure from our method with reference measurements. Overall, the correlation attains good values for all measured locations. For comparison, we also applied two time-resolved approaches, which attained values of correlation similar to our approach. The performance of the 2D TH method is further
assessed on 3D time-resolved velocity data for a turbulent boundary layer and compared with 3D methods. The root-meansquare (RMS) pressure fluctuations of the 2D TH, 3D TH and 3D pseudo-Lagrangian methods closely follow the pressure fluctuation distribution from DNS. These observations on the RMS pressure estimates are further supported by similar
analysis on synthetic PIV data (based on DNS) of a turbulent channel flow. The values of spatial correlation between the 2D TH method and the DNS pressure fields in this case, are similar to the temporal correlations achieved in the turbulent flow over the ribs. Finally, we discuss the accuracy of instantaneous pressure estimates and provide a rule of thumb to determine regions where the pressure fluctuation estimate from the 2D TH methods is likely to fail.
在一个双稳湍流涡旋火焰中,对间歇性动态的时间-频率定位
Particle-laden Taylor-Couette流:高阶转变和径向局部波浪涡旋的证据
7根杆束的流体-结构相互作用:用实验数据对比数值模拟
相关产品
汽车光学检测系统AIS
PT403型波长可调谐皮秒激光器
ANL系列高能量高重复频率DPSS纳秒激光器
APL4206 系列高能量皮秒激光放大器
UltraFlux FF/FT 5000 高能量可调谐飞秒激光器系统
UltraFlux FT300型波长可调谐飞秒激光器系统
Ekspla 超高功率激光器系统SYLOS 2A
LaVision PTUx 可编程时间控制单元
LaVision 用于粒子成像测速PIV的相机
LaVision StrainMaser 全场应变测试系统组件
LaVision 用于数字图像相关DIC的相机
LaVision StrainMaster 数字图像相关分析软件包
LaVision 标定板
LaVision StrainMaster 形变应变成像测量系统
LaVision StrainMaster DVC 体视全场应变测量系统
关注
拨打电话
留言咨询