摘要
直升机旋翼桨尖涡特性研究是直升机旋翼气动特性研究的关键要素,为提高对旋翼悬停状态桨尖涡特性的认识以及准确掌握其流动机理,利用Bo-105旋翼模型在Φ5 m立式风洞开口试验段进行了桨尖马赫数相似情况下的悬停试验,并采用TR-PIV流场测量系统对旋翼悬停状态下不同总距时的流场进行了精细化测量,得到了该副旋翼32帧/圈的详细流场图像,并运用更为合理的涡核中心判定、涡核流动数据提取以及涡核模型拟合方法对试验结果进行了精细化处理与分析,进一步揭示了旋翼模型悬停状态下桨尖涡的演化发展过程.研究表明:高速PIV设备能准确捕捉旋翼悬停状态下的流场运动特征,有助于旋翼流场的精细化研究;采用涡量加权平均的方法来计算涡核中心位置可以消除涡核中心平移速度的影响,进而更加准确地定位涡核中心;采用环量分析的方法可以更加可靠地确定涡核尺寸和最大诱导速度,且分析结果显示随涡龄角的增加,涡核半径缓慢增大、涡核最大诱导速度缓慢减小;在桨尖涡发展演化过程中,不同发展阶段具有不同的涡核模型n参数.
Research on characteristics of helicopter rotor blade tip vortex is one of the key elements for helicopter rotor aerodynamic characteristics research. To improve the understanding of the blade tip vortex characteristics under hovering status and grasp the flow mechanism accurately,the Bo-105 rotor model hover test of tip Mach number similarity is conducted in open test section of Φ5 m vertical wind tunnel. In the same time,the hovering rotor flow filed of different collective pitches is measured elaborately with the TR-PIV measurement system,and then the detailed flow field（32 frames/circle） of this rotor is obtained. Based on the reasonable methods of the judgment of vortex center,extraction of vortex core flow parameter and fit of the vortex core model,the test results is processed and analyzed elaborately,and the evolution and development of blade tip vortex under hovering status is uncovered.The research shows that TR-PIV can catch the vortex characteristics correctly,and it will contribute to the elaborate study of rotor flow filed; using the weighted average of vorticity to calculate vortex center,it can avoid influence of shift speed on position of vortex core,and position of the vortex core accurately; using the circulation-based method,it can calculate size of vortex core and max induced velocity more reliably,and the results show that vortex core radius increases slowly and vortex core max induced velocity slowly decreases with increasing wake age; during the evolution of tip vortex,different development stages have different n parameters.
作者
黄明其
武杰
何龙
兰波
HUANG Mingqi, WU Jie, HE Long, LAN Bo(Low Speed Aerodynamics Institute, China Aerodynamics Research ＆ Development Center, Mianyang 621000, Sichuan, Chin)
出处
《哈尔滨工业大学学报》
EI
CAS
CSCD
北大核心
2018年第4期124-130,共7页
Journal of Harbin Institute of Technology
