Lagrangian and Eulerian pressure field evaluation of rod-airfoil flow from time-resolved tomographic PIV
Lagrangian and Eulerian pressure field evaluation of rod-airfoil flow from time-resolved tomographic PIV
复制标题
DOI：
10.1007/s00348-010-1011-0
复制
发表时间：
2011-04
影响因子：
2.4
通讯作者：
D. Violato;P. Moore;F. Scarano
中科院分区：
文献类型：
--
作者：
D. Violato;P. Moore;F. Scarano
这项工作通过时间分辨断层粒子图像测速（TR-TOMO PIV）在薄光体积配置中研究了杆翼型气流。实验在靠近嵌入圆柱杆冯卡门尾迹的 NACA0012 翼型前缘的区域进行。在 5 kHz 下测量的 3D 速度场用于通过压力梯度场的积分来评估瞬时平面压力场。实验数据采用基于多个速度测量的离散模型进行处理。必须考虑用于沿着流体块轨迹评估拉格朗日导数的时间间隔，以减少精度误差。通过比较拉格朗日方法和欧拉方法，后者仅限于较短的时间间隔，并且发现如果要求相对精度误差低于10%，则不适用于评估压力梯度场。最后，将通过层析速度测量评估的压力与通过模拟平面速度测量获得的压力进行比较，以讨论 3D 流动现象对所提出技术的准确性的影响。
This work investigates the rod-airfoil air flow by time-resolved Tomographic Particle Image Velocimetry (TR-TOMO PIV) in thin-light volume configuration. Experiments are performed at the region close to the leading edge of a NACA0012 airfoil embedded in the von Kármán wake of a cylindrical rod. The 3D velocity field measured at 5 kHz is used to evaluate the instantaneous planar pressure field by integration of the pressure gradient field. The experimental data are treated with a discretized model based on multiple velocity measurements. The time separation used to evaluate the Lagrangian derivative along a fluid parcel trajectory has to be taken into account to reduce precision error. By comparing Lagrangian and Eulerian approaches, the latter is restricted to shorter time separations and is found not applicable to evaluate pressure gradient field if a relative precision error lower than 10% is required. Finally, the pressure evaluated from tomographic velocity measurements is compared to that obtained from simulated planar ones to discuss the effect of 3D flow phenomena on the accuracy of the proposed technique.