Flow Visualization in the Branching Duct by Using Particle Imaging Velocimetry

입자영상유속계를 이용한 분기관내 유동가시화

  • No, Hyeong-Un (Dept. of Mech. Eng., Soongsil University) ;
  • Seo, Sang-Ho (Dept. of Mech. Eng., Soongsil University) ;
  • Yu, Sang-Sin (Dept. of Mech. Eng. and Design, Hankuk Aviation University)
  • 노형운 (숭실대학교 기계공학과) ;
  • 서상호 (숭실대학교 기계공학과) ;
  • 유상신 (한국항공대학 기계설계학과)
  • Published : 1999.02.01

Abstract

The objective of this study is to analyse the flow field in the branching duct by visualizing the flow phenomena using the PIV system. A bifurcation model is fabricated with transparent acrylic resin to visualize the whole flow field with the PIV system. Water was used as the working fluid and the conifer powder as the tracer particles. The single-frame and two-frame methods of the PIV system and 2-frame of the grey level correlation method are applied to obtain the velocity vectors from the images captured in the flow filed. The velocity distributions in a lid-driven cavity flow are compared with the so-called standard experimental data, which was obtained from by 4-frame method in order to validate experimental results of the PIV measurements. The flow patterns of a Newtonian fluid in a branching duct were successfully visualized by using the PIV system and the sub-pixel and the area interpolation method were used to obtain the final velocity vectors. The velocity vectors obtained from the PIV system are in good agreement with the numerical results of the 3-dimensional branch flow. The results of numerical analyses and the PIV experiments for the three-dimensional flows in the branch ing duct show the recirculation zone distal to the branching point and the sizes of the recirculation length and height of the tow different methods are in good agreement.