Application of High Resolution PIV Processing in Flow Through Mechanical Heart Valve

Abstract

Particle image velocimetry (PIV) processing techniques, Multi Pass Correlation (MPC) and Particle Tracking Velocimetry (PTV), are applied to images obtained from a bileaflet mechanical heart valve study to obtain velocity measurements with increased spatial resolution and accuracy. Using subregions of 32 pixels by 64 pixels, a spatial resolution of 0.23 mm in x and 0.46 mm in y is obtained, as compared to 0.46 mm in both directions for traditional PIV processing. When MPC and PTV are not utilized, spatial resolution can only be increased by decreasing the subregion size and time between images in an image pair, which sacrifices accuracy. High accuracy can only be obtained by increasing the subregion size and the time between pulses, which reduces spatial resolution. MPC and PTV allow both high spatial resolution and accuracy by altering the processing method as opposed to how the data is produced conventionally.