Measurement of velocity profiles and turbulence intensity using MR phase velocity mapping

Magnetic resonance (MR) phase velocity mapping was used to measure velocity profiles and turbulence intensities in straight tube turbulent flow and flow downstream of a 90% stenosis. In straight tube flow, the MR velocity profiles and turbulence intensity measurements were accurate when compared t previously published data. MR velocity profiles downstream of the stenosis exhibited features common to post-stenotic flow fields. The MR measurements compared well to previously published LDA profiles, except the MR profile showed a shorter reattachment length. The vibrations from the MR scanner may affect the turbulent transition point and hence the location of the reattachment point downstream of the stenosis. MR turbulence intensity measurements downstream of the stenosis had comparable magnitudes but did not correspond in location to the LDA measurements. The discrepancy was presumably due to the differences in reattachment points between the MR and LDA measurements.