• Title/Summary/Keyword: 스테레오 입자추적유속계

Search Result 3, Processing Time 0.017 seconds

Measurements of a Ship's Propeller Wake with Stereoscopic-PIV and Stereoscopic-PTV (스테레오 PTV와 스테레오 PIV에 의한 선박프로펠러 후류측정)

  • Doh, Deog-Hee;Hwang, Tae-Gyu;Lee, Sang-Joon
    • Journal of the Korean Society of Visualization
    • /
    • v.5 no.2
    • /
    • pp.26-32
    • /
    • 2007
  • Stereoscopic PTV and Stereoscopic-PIV measurements have been carried out for the studies of the wake of a ship's propeller. Stereoscopic photogrammetry based on a 3D-PTV principle was introduced using two high-definition cameras(1k x 1k, 30Hz). The arrangement of the two cameras was based on angular position. The pair-matching of the three-dimensional velocity vectors were based on Genetic Algorithm based 3D-PTV technique. The results obtained by both measurement systems have been compared at the advance ratio J=0.88(290 rpm, d=54 mm). Turbulent properties have also been compared each other at the same condition.

Single Camera 3D-Particle Tracking Velocimetry-Measurements of the Inner Flows of a Water Droplet (단일카메라 3차원 입자영상추적유속계-액적내부 유동측정)

  • Doh, Deog-Hee;Sung, Hyung-Jin;Kim, Dong-Hyuk;Cho, Kyeong-Rae;Pyeon, Yong-Beom;Cho, Yong-Beom
    • 한국가시화정보학회:학술대회논문집
    • /
    • 2006.12a
    • /
    • pp.1-6
    • /
    • 2006
  • Single-Camera Stereoscopic Vision three-dimensional measurement system has been developed based upon 30-PTV algorithm. The system consists of one camera $(1k\times1k)$ and a host computer. To attain three-dimensional measurements a plate having stereo holes has been installed inside of the lens system. Three-dimensional measurements was successfully attained by adopting the conventional 30-PTV camera calibration methods. As applications of the constructed measurement system, a water droplet mixed with alcohol was constructed on a transparent plastic plate with the contacted fluid diameter 4mm, and the particles motions inside of the droplet have been investigated with the constructed measurement system. The measurement uncertainty of the constructed system was 0.04mm, 0.04mm and 0.09mm for X, Y and Z coordinates.

  • PDF

Single-Camera Micro-Stereo 4D-PTV (단일카메라 마이크로 스테레오 4D-PTV)

  • Doh, Deog-Hee;Cho, Young-Beom;Lee, Jae-Min;Kim, Dong-Hyuk;Jo, Hyo-Jae
    • Transactions of the Korean Society of Mechanical Engineers B
    • /
    • v.34 no.12
    • /
    • pp.1087-1092
    • /
    • 2010
  • A micro 3D-PTV system has been constructed using a single camera system. Two viewing holes were created behind the object lens of the microscopic system to construct a stereoscopic viewing image. A hybrid recursive PTV algorithm was used. A concept of epipolar line was adopted to eliminate many spurious candidates. Three-dimensional velocity vector fields were obtained by calculating the three-dimensional displacements of particles that were identified as being identical. The system consists of a laser light source (Ar-ion, 500 mW), one high-definition camera ($1028{\times}1024$ pixels, 500 fps), a circular plate with two viewing holes, and a host computer. The performance of the developed algorithm was tested using artificial images. The characteristic of the vector recovery ratio was investigated for the particle numbers. A micro backward-facing step channel ($H{\times}h{\times}W:\;36{\mu}m{\times}70{\mu}m{\times}3000{\mu}m$) was measured using the developed measurement system. The results were in good qualitative agreement with other results.