Development Of Four-Dimensional Digital Speckle Tomography For Experimental Analysis Of High-Speed Helium Jet Flow

고속 헬륨 제트 유동의 실험적 분석을 위한 4차원 디지털 스펙클 토모그래피 기법 개발

  • Ko, Han-Seo (School of Mechanical Engineering, Sungkyunkwan University) ;
  • Kim, Yong-Jae (School of Mechanical Engineering, Sungkyunkwan University)
  • 고한서 (성균관대학교 기계공학부) ;
  • 김용재 (성균관대학교 기계공학부)
  • Published : 2006.06.15


A high-speed and initial helium jet flow has been analyzed by a developed four-dimensional digital speckle tomography. Multiple high-speed cameras have been used to capture movements of speckles in multiple angles of view simultaneously because a shape of a nozzle for the jet flow is asymmetric and the initial jet flow is fast and unsteady. The speckle movements between no flow and helium jet flow from the asymmetric nozzle controlled by a solenoid valve have been obtained by a cross-correlation tracking method so that those distances can be transferred to deflection angles of laser rays for density gradients. The four-dimensional density fields for the high-speed helium jet flow have been reconstructed from the deflection angles by a developed real-time tomography method.


Digital Speckle Tomography;Hydrogen Flow;High-speed Helium Flow;Multiplicative Algebraic Reconstruction Technique (MART);Cross-correlation


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