Quantitative Flow Field Visualization of a Flow inside an Opaque Tube Using Angiographic PIV Method

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Guk Bae Kim, Nam Yun Lim, Jae Chun Ryu, Dae Hyun Yim, Hyung Koo Lee and Sang Joon Lee

Key Words : Cardiac vascular disease ( ), Angiographic PIV, X-ray tube (X ), Shutter system ( )

Abstract

To diagnose circulatory diseases in the viewpoint of hemodynamics, we need to get quantitative hemodynamic information of blood flows related with the vascular diseases with high spatial resolution of tens micrometer and high temporal resolution in the order of millisecond. For investigating in-vivo hemodynamic phenomena, a new diagnosing technique combining medical radiography and PIV method was newly proposed and developed. This angiographic PIV technique consists of a medical X-ray tube, an X-ray CCD camera, a shutter module for double pulses of X-ray, and a synchronizer. The feasibility of the angiographic PIV technique was tested and quantitative flow velocity field distribution of a flow inside an opaque conduit was acquired by the developed system. It can be used for measuring flow phenomena of non- transparent fluids inside opaque conduits.

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2.1 Concept of angiographic PIV method

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Flow visualization

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Table 1 Specification of X-ray CCD camera Effective area 36 × 23.6 mm² Number of pixel 4000^(H) × 2672^(V) Cell size (pixel pitch) 9 µm

Scintillator thickness 100 µm Fast repetition readout mode for PIV

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2.3 Performance test

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Fig. 6 Average velocity field distribution of a tube flow

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X position (mm)

Velocity (mm/s)

PIV result Theory

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