Systems exhibiting complex, coupled physics such as multiphase flow devices require computer simulations to capture their behavior in detail. These models are multiscale in nature, requiring detailed models of small systems to capture the complete physics and create coarse-grained models to capture the salient features of industrial-scale devices. In the Boyce group, we seek to develop accurate models at all levels, constantly working with experiments to validate models and uncover important physical mechanisms.
MRI has long been used as a powerful tool for investigating the interior of the human body. The principles of MRI extend just as well to other opaque 3D systems, such as chemical reactors, geological flows and water purification devices. Since MRI is built upon the principles of nuclear magnetic resonance, it cannot only create 3D images, but also monitor chemical reactions, temperature, mass transport, flow and diffusion on a spatially resolved level.
A previous study from the collaboration between our group and Prof. Müller’s group at ETH Zurich investigated the bubble behavior and particle velocity in 3D freely bubbling fluidized beds with real-time MRI (Industrial & Engineering Chemistry Research 57, 9674). Using these rich data sets as benchmarks, we critically evaluated the accuracy of sub-models in two fluid modeling of fluidized beds, including the drag law and particle stress closure relationships.
Previously, using real-time magnetic resonance imaging (MRI), we found two anomalous bubble collapse phenomena that show the manifestation of an instability when two bubbles interact in a fluidized bed (Phys. Rev. Fluids 4, 034303). It was shown that (1) a bubble collapses when two bubbles are injected side-by-side and (2) a lower, smaller bubble collapses trailing an upper, larger bubble. Later, a CFD-DEM study (Phys.
Dr. rer. nat. Wasif Zia received a National Distinction before starting his doctorate at RWTH Aachen University, Germany, where he also co-authored a leading textbook on compact/mobile NMR devices (Compact NMR, De Gruyter Boston/Berlin 2014).
He holds the world record in the smallest permanent magnet based novel MR devices including single-sided, and closed Halbach-like geometries. He specializes in data acquisition techniques and MR methodologies to tackle low signal, high noise environments.