HPIVによる三次元密度・流速分布同時測定法の開発 : 第1報, ホログラム同時記録/分離再生の検討 (<小特集>画像処理応用熱流体計測)

抄録

In this study, the simultaneous measurement technique for three-dimensional density and three-dimensional velocity distributions was evaluated. The Holographic Particle Image Velocimetry (HPIV) was the technique to record the three-dimensional position of the tracer particle on the hologram. When there were density distributions in the interrogation region, the plane optical wave may be modulated because of the difference of the refraction indices. Then, both of the plane wave modulated by density and the spherical wave by particle scatter were interfered with the reference beam, being recorded on the single hologram. With reconstructing the hologram, the both of the modulated plane wave and spherical wave were reconstructed. Since the plane wave and spherical wave belong to low and high spacial frequency, respectively, the plane wave was reconstructed with the low-pass filter, resulting in the information of the density distributions to be obtained. With the high pass filter, the particle three dimensional positions were determined, i.e., the same procedure with the original HPIV technique. The effectiveness of the proposed technique (Filtering Extraction: FX) was confirmed through the Helium Jet experiment. The information of the density and velocity were separately measured.