Dynamical Flow Tomography by Laser Induced Fluorescence
Laser induced fluorescence (LIF) imaging is a well developed method to directly obtain the 2D structure of a flow by imaging chemical species which emit a sufficient signal to be detected. The principles of LIF are also applicable to a 3D-imaging technique. The first one to put this into practice was Dahm et al.[l], others are Merkel and Dracos et al.. This work presents the development of a new 3D-LIF imaging method where the illuminating laser beam is swept parallel to the imaging sensor and a volume of 45×45×18 mm dimension is recorded with a resolution of 256×256×90 pixels. The obtained 3D images are evaluated to extract the velocity, vorticity, and rate-of-strain tensor fields from the grey level distribution by an alternative technique to . Also some experimental evaluations are presented briefly.
KeywordsDirect Numerical Simulation Laser Induce Fluorescence Fluorescent Tracer Velocity Gradient Tensor Unstable Node
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