Vertical bore magnet for magnetic resonance imaging of multiphase of multiphase dynamics

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Paul Lauterbur and Sir Peter Mansfield were awarded the Nobel Prize 2003 in Medicine for their invention of Magnetic Resonance Imaging (MRI), which had a tremendous impact on clinical diagnostics. MRI is a very flexible technique, capable of obtaining information inaccessible by other methods. MRI has great promise in materials science and engineering, particularly in areas that require a non-invasive measurement. We plan to concentrate on three areas. Multiphase flows (flow of liquid and gas) are employed industrially for conducting catalytic reactions and in the nuclear industry for cooling nuclear reactors. Combustion is pivotal in many branches of manufacturing and engineering. Cavitation (dynamically active bubbles that appear in a liquid as a result of a pressure drop) is increasingly used in industry. All three processes are important for industry, and, at the same time, our understanding of the transport phenomena in all of them is still limited. Commonly employed computational methods require a direct experimental verification, which is very difficult to perform without interfering with the process under study. MRI, as a non-invasive technique, has a great potential in this field. In all of these applications, there is a natural vertical orientation dictated by gravity: flames, bubbles and hot fluids will always rise upward. There are also problems with MRI measurements associated with gas-liquid boundaries: they will affect a local magnetic field, producing susceptibility artefacts at higher magnetic fields. This funding has purchased an MRI magnet to study multiphase flow, cavitation and combustion. Such a magnet must have a vertical bore so that gravity will have the same effect on samples inside the magnet as it does in the industrial and natural environments. The field of the magnet will be of a medium strength (4.8 T) to reduce susceptibility artefacts and yet maintain an acceptable signal-to-noise ratio.