Noninvasive 4D Flow Characterization in a Stirred Tank via Phase-Contrast Magnetic Resonance Imaging

The present work demonstrates that a non-invasive quantification of the hydrodynamics in a stirred tank in space and time is possible using flow sensitive phase-contrast magnetic resonance imaging (PC-MRI) at 7 Tesla (7T). The experimental technique has been developed for a batch crystallizer, but is applicable in principle for a variety of stirred-tank reactors and rotating systems. The PC-MRI technique is able to characterize the unsteady periodic three-dimensional flow velocities with acceptable spatial and temporal resolution, and does not imply that optically transparent fluids are employed. PC-MRI is already widely used for medical diagnostics in order to determine the blood flow velocities, e.g., for cardiovascular applications. However, the utilization of this method is still new for engineering problems, including process engineering. It is therefore important to check the applicability of PC-MRI to applications of practical interest in this field and complement other flow measurement and simulation techniques.