Development of ultrafast UTE imaging for granular systems.
Ultrashort echo time (UTE) imaging is commonly used in medical MRI to image 'solid' types of tissue; to date it has not been widely used in engineering or materials science, in part due to the relatively long imaging times required. Here we show how the acquisition time for UTE can be reduced to enable a preliminary study of a fluidized bed, a type of reactor commonly used throughout industry containing short T2∗material and requiring fast imaging. We demonstrate UTE imaging of particles with a T2∗of only 185μs, and an image acquisition time of only 25ms. The images are obtained using compressed sensing (CS) and by exploiting the Hermitian symmetry of k-space, to increase the resolution beyond that predicted by the Nyquist theorem. The technique is demonstrated by obtaining one- and two-dimensional images of bubbles rising in a model fluidized bed reactor.
Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge CB2 3RA, United Kingdom.
Hilary T
HT
Fabich
Department of Chemical Engineering and Biotechnology, University of Cambridge, New Museums Site, Pembroke Street, Cambridge CB2 3RA, United Kingdom.
Andrew J
AJ
Sederman
Department of Chemical and Process Engineering, University of Canterbury, Private Bag 4800, Christchurch, New Zealand. Electronic address: daniel.holland@canterbury.ac.nz.
Daniel J
DJ
Holland
Granular flow; MRI; Rapid MRI; UTE; Ultrashort echo time