明渠均匀流简易粒子图像测速技术浅析
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摘要
粒子图像测速系统PIV是一种近年兴起并发展迅速的非接触式流体测量方式,通过测量示踪粒子在很短时间间隔内的位移来间接地测量流场的速度分布,具有高精度、多点位和瞬时态等优点,但其需要高功率激光片光来定位速度剖面和照亮示踪粒子,高昂的价格和维修费用使得人们需要找到一种非激光照明式PIV作为替代。结合明渠均匀流的断面流速测量特点及工作原理,使用LED光照亮示踪粒子,并运用摄影原理窄束景深得到清晰的速度矢量场图形。经过分析发现,测量结果与理论公式所得值吻合良好,说明该技术在均匀流流态中具有较高精确性和实用性。
The particle image velocimetry system, PIV is a non-contact fluid measurement method that has been rising and developed rapidly in recent years. It measures the velocity distribution of the flow field indirectly by measuring the displacement of the tracer particles in a short time interval. It has some advantages in high precision, multi-point and transient state, but it requires high power laser light to locate velocity profile and illuminate tracer particles. It takes high cost and maintenance costs to make us find a non-laser-illuminated PIV as an alternative. Combined with the characteristics and working principle of the cross-section flow velocity of the uniform flow in the open channel, the LED light is used to illuminate the tracer particles, and the narrow-band depth of field is used to obtain a clear velocity vector field pattern. After analysis, it is found that the measured results agree well with the theoretical formula, indicating that the technique has high accuracy and practicability in uniform flow regime.
The particle image velocimetry system, PIV is a non-contact fluid measurement method that has been rising and developed rapidly in recent years. It measures the velocity distribution of the flow field indirectly by measuring the displacement of the tracer particles in a short time interval. It has some advantages in high precision, multi-point and transient state, but it requires high power laser light to locate velocity profile and illuminate tracer particles. It takes high cost and maintenance costs to make us find a non-laser-illuminated PIV as an alternative. Combined with the characteristics and working principle of the cross-section flow velocity of the uniform flow in the open channel, the LED light is used to illuminate the tracer particles, and the narrow-band depth of field is used to obtain a clear velocity vector field pattern. After analysis, it is found that the measured results agree well with the theoretical formula, indicating that the technique has high accuracy and practicability in uniform flow regime.
引文
[1] AIAA. PIV with LED:Particle Shadow Velocimetry(PSV)Technique[J].
[2] Buchmann N A, Willert C E,Soria J. Pulsed, high-power LED illumination for tomographic particle image velocimetry[J].Experiments in Fluids, 2012, 53(5):1545-1560.
[3] Willert C, Stasicki B, Klinner J, et al. Pulsed operation of high-power light emitting diodes for imaging flow velocimetry[J]. Measurement Science&Technology, 2010, 21(21):129-247.
[4] Stasicki B, Kompenhans J. Pulsed high-power LED illuminator for the visualisation and measurement of flows[J]. International Journal of Rock Mechanics&Mining Sciences, 2010, 37(s 1-2):437-443.
[5] Geoghegan P H, Buchmann N A, Soria J, et al. High-speed LED-illuminated PIV measurements of the time-dependent flow field in a stenosed, compliant arterial model[C]//Int Symp on Applications of Laser Techniques To Fluid Mechanics. 2012.
[6]杜海,孟娟,李木国,等.粒子图像测试实验中的图像采集控制方法[J].实验室研究与探索,2017, 36(4):11-15.
[7]柯森繁,石小涛,王恩慧,等.简易粒子图像测速(PIV)技术开发与优化技巧[J].长江科学院院报, 2016, 33(8):144-150.
[2] Buchmann N A, Willert C E,Soria J. Pulsed, high-power LED illumination for tomographic particle image velocimetry[J].Experiments in Fluids, 2012, 53(5):1545-1560.
[3] Willert C, Stasicki B, Klinner J, et al. Pulsed operation of high-power light emitting diodes for imaging flow velocimetry[J]. Measurement Science&Technology, 2010, 21(21):129-247.
[4] Stasicki B, Kompenhans J. Pulsed high-power LED illuminator for the visualisation and measurement of flows[J]. International Journal of Rock Mechanics&Mining Sciences, 2010, 37(s 1-2):437-443.
[5] Geoghegan P H, Buchmann N A, Soria J, et al. High-speed LED-illuminated PIV measurements of the time-dependent flow field in a stenosed, compliant arterial model[C]//Int Symp on Applications of Laser Techniques To Fluid Mechanics. 2012.
[6]杜海,孟娟,李木国,等.粒子图像测试实验中的图像采集控制方法[J].实验室研究与探索,2017, 36(4):11-15.
[7]柯森繁,石小涛,王恩慧,等.简易粒子图像测速(PIV)技术开发与优化技巧[J].长江科学院院报, 2016, 33(8):144-150.