B211 PIV計測における精度の検討

抄録

Accuracy of PIV (particle image velocimetry) is assessed using simulated images to clarify the advantage of the cross-correlation method. Heterogeneously random particle-distributions in the image are estimated so as to meet their auto-correlation functions with those really obtained in the measurement. Probable errors due to out-of-section, random and rotational motions are individually considered. The results show that to suppress an error due to appearance and disappearance of particles, it is desirable to distribute particles uniformly in the test section, whereas to suppress an error due to random motions and rotational motions, it is desirable to distribute the particle heterogeneously. Furthermore, time-sequential analysis for obtaining mean velocity and turbulence intensity is attempted and their accuracy is discussed based on comparison with measurement from HWA (hotwire anemometry). Good agreements with those two methods indicate the feasibility of the PIV measurement, which may successfully supply the information about turbulence characteristics.