Ultra-fast velocity imaging in stenotically produced turbulent jets using RUFIS.
A method for rapidly producing velocity images is presented. This sequence combines a modified bipolar gradient pulse to magnitude encode the velocity with the rotating ultra-fast imaging sequence (RUFIS) to image the encoded spins. Velocity encoding is done in 3 msec, and RUFIS acquires 32 projections in 8 msec. The method is applied to turbulent jets associated with a 75% stenosis in a 15-mm inner diameter glass pipe. Data is acquired upstream and downstream from the stenosis for Reynolds numbers from 560 to 3750. In addition, a robust method of reconstructing the unobserved short time region of a free induction decay is presented and incorporated into the image processing.
Madio
D P
DP
Department of Physics and Astronomy, University of Pittsburgh, Pennsylvania, USA.
Gach
H M
HM
Lowe
I J
IJ
D007091:Image Processing, Computer-Assisted; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008961:Models, Structural; D012212:Rheology; D012399:Rotation