Blade tip vortex measurements of a hovering rotor
-
摘要: 为了研究旋翼桨尖涡涡核结构，采用粒子图像测速（PIV）技术对4m直径桨尖开孔旋翼在悬停状态的桨尖涡流场进行了详细测量，获得了旋翼145°方位角处桨尖涡附近流场的速度分布，以及桨尖涡的涡核半径、旋转速度和涡量分布等试验数据，并研究了PIV分析中选取不同审查窗尺寸对桨尖涡结构测量结果的影响。为了避免桨尖涡位置不稳定的影响，提出了基于桨尖涡流场速度特征的条件平均法，并与简单平均法和基于涡量峰值的条件平均法进行了对比，验证了对桨尖涡流场进行条件平均的必要性，以及所提出的条件平均法的有效性。Abstract: In order to investigate the structure of blade tip vortices, Panicle Image Velocimetry (PIV) measurements were conducted on tip vortices trailing from the rotor with slotted blade to quantify the swirl velocity, core radius and vorticity profile at a fixed wake angle of 145 degree. The influence of the PIV image analysis parameters, e.g. sampling window size, on the vortex structure parameters has been investigated. To mitigate the effects of vortex wander, a scheme to align the velocity fields based on the locations where the velocity minimum appears prior to averaging was developed. Compared to simple average, the conditional average method obtains more accurate parameters of the vortex.
-
Key words:
- rotor /
- hovering /
- tip vortex /
- flow field /
- PIV
-
图 6 桨尖涡流场矢量图(简单平均法)
Figure 6. Velocity vector field of blade tip vortex (simple average)
图 7 桨尖涡流场矢量图(条件平均法一)
Figure 7. Velocity vector field of blade tip vortex (conditional average: method one)
图 8 桨尖涡流场矢量图(条件平均法二)
Figure 8. Velocity vector field of blade tip vortex (conditional average: method two)
图 10 不同平均方法对桨尖涡切向速度的影响
Figure 10. Comparison of blade tip vortex tangential velocity profiles
表 1 不同审查窗尺寸获得的涡核参数对比
Table 1. Comparison of vortex characteristics obtained with different interrogation window sizes
审查窗口尺寸 Lm/c rc/c Lm/rc Vθ/ΩR 24pixel×24pixel 1.4% 7.9% 18.1% 10.1% 32pixel×32pixel 1.9% 8.2% 23.5% 9.9% 40pixel×40pixel 2.4% 9.0% 26.6% 9.7% 48pixel×48pixel 2.9% 9.4% 30.7% 9.7% 
下载: 导出CSV
表 2 不同平均方法获得的涡核参数对比
Table 2. Comparison of vortex characteristics obtained with different average methods
Average method rc/c Vθ/ΩR Simple average 13.0% 10.0% Conditional average one 10.5% 11.0% Conditional average two 9.4% 11.1%
下载: 导出CSV
-
[1] Coyne A J, Mahendra J B, Leishman J D. Investigation into the rollup and diffusion of rotor tip vortices using laser Doppler velocimetry[C]. 53th Annual Forum of the American Helicopter Society, Viginia Beach, VA, 1997. [2] Martin P B, Pugliese J G, Leishman J G. High resolution trailing vortex measurements in the wake of a hovering rotor[C]. 57th Annual Forum of the American Helicopter Society, Washington D C, 2001. [3] Heineck J T, Yamauchi G K, Woodcock A J, et al. Application of three-component PIV to a hovering rotor wake[C]. 56th Annual Forum of the American Helicopter Society, Virginia Beach, VA, USA, 2000. [4] Martin P B, Pugliese J G, Leishman J G, et al. Stereoscopic PIV measurements in the wake of a hovering rotor[C]. 56th Annual Forum of the American Helicopter Society, Virginia Beach, USA, 2000. [5] Richard H, Raffel M. Rotor wake measurements:Full-scale and model tests[C]. 58th Annual Forum of the American Helicopter Society, Montreal, Canada, 2002. [6] van der Wall B G, Richard H. Analysis methodology for 3C PIV data[C]. 31th European Rotorcraft Forum, Florence, Italy, 2005. [7] Wadcock1 A J, Yamauchi G K, Solis E, et al. PIV measurements in the wake of a full-scale rotor in forward flight[C]. 29th AIAA Applied Aerodynamics Conference, Honolulu, Hawaii, 2011. [8] Splettstoesser W R, van der Wall B G, Junker B, et al. The ERATO programme:wind tunnel results and proof of design for an aeroacoustically optimized rotor[C]. 25th European Rotorcraft Forum, Rome, Italy, 1999. [9] Murashige A, Kobiki N, Tsuchihashi A, et al. ATIC aeroacoustic model rotor test at DNW[C]. 24th European Rotorcraft Forum, Marseilles, France, 1998. [10] Murashige A, Kobiki N, Tsuchihashi A, et al. Second ATIC aeroacoustic model rotor testat DNW[C]. 26th European Rotorcraft Forum, The Hague, Netherlands, 2000. [11] Burley C, Brooks T B, van der Wall B, et al. Rotor wake vortex definition-initial evaluation of 3-C PIV results of the hart-Ⅱ study[C]. 26th European Rotorcraft Forum. Bristol, England, 2002. [12] 杨永东, 武杰.悬停旋翼桨尖涡的试验研究[J].实验流体力学, 2008, 22(3):36-39. http://www.syltlx.com/CN/abstract/abstract9669.shtmlYang Y D, Wu J. Investigation of hovering rotor tip vortex[J]. Journal of Experiments in Fluid Mechanics, 2008, 22(3):36-39. http://www.syltlx.com/CN/abstract/abstract9669.shtml [13] 袁红刚, 李进学, 杨永东, 等.悬停状态下旋翼尾迹测量试验研究[J].空气动力学报, 2010, 28(3):306-309. http://www.cnki.com.cn/Article/CJFDTOTAL-KQDX201003012.htmYuan H G, Li J X, Yang Y D, et al. Test investigation of measuring wake geometry for helicopter rotors in hover[J]. Acta Aerodynamica Sinica, 2010, 28(3):306-309. http://www.cnki.com.cn/Article/CJFDTOTAL-KQDX201003012.htm [14] 袁红刚, 李进学, 杨永东, 等.前飞状态下旋翼尾迹测量试验研究[J].实验流体力学, 2010, 24(4):29-32. http://www.syltlx.com/CN/abstract/abstract9861.shtmlYuan H G, Li J X, Yang Y D, et al. Test investigation of measuring wake geometry for helicopter rotors in forward flight[J]. Journal of Experiments in Fluid Mechanics, 2010, 24(4):29-32. http://www.syltlx.com/CN/abstract/abstract9861.shtml [15] 黄水林, 林永峰, 黄建萍, 等.基于PIV技术的纵列式双旋翼尾迹特性实验研究[J].空气动力学报, 2012, 30(3):334-339. http://www.cnki.com.cn/Article/CJFDTOTAL-KQDX201203010.htmHuang S L, Lin Y F, Huang J P, et al. Expermental investigation on the wake characteristics of tandem twin rotors[J]. Acta Aerodynamicsa Sinica, 2012, 30(3):334-339. http://www.cnki.com.cn/Article/CJFDTOTAL-KQDX201203010.htm [16] Grant I. Particle image velocimetry:a review[J]. Proceedings of the Institution of Mechanical Engineers, 1997, 211:55-76. https://researchportal.hw.ac.uk/en/publications/particle-image-velocimetry-a-review-2 -
点击查看大图
计量
- 文章访问数: 201
- HTML全文浏览量: 105
- PDF下载量: 11
- 被引次数: 0
