TIME-RESOLVED STEREO PIV MEASUREMENT OF PULSATILE FLOW IN AN ARTERY MODEL

摘要

This study investigated the behavior of pulsatile blood flow in a curved pipe that simulates the internal carotid artery (ICA), which is a common location for an aneurysm. Since complex secondary flow arises due to the curvature of artery, particle image velocimetry (PIV) was applied to obtain detailed flow information from in vitro experiments. However, blood flow in arteries is pulsatile and time-resolution of conventional PIV is not adequate for capturing the transient behavior of pulsatile flow. Thus, time-resolved PIV, which consists of high-speed cameras and high repetition rate lasers, was applied to measure unsteady flow. This new measurement method can provide superior resolution in space and in time. Here, we demonstrate an improvement in resolution in space from a two-dimensional PIV system as compared to a stereo PIV system. To perform stereo calibration within a narrow and complex measurement area, we developed a non-invasive stereo calibration technique using lasers. Stereo time-resolved PIV measurement allows the observation of two-dimensional, three-component transient flow structure. Pairs of secondary-flow vortices have different momentum and affect one other significantly. Flow characteristics at the systole phase are drastically different from those at the diastole phase, even with a similar Reynolds number.