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

保罗·劳特布尔和彼得·曼斯菲尔德爵士因发明核磁共振成像(MRI)而被授予2003年诺贝尔医学奖，这项发明对临床诊断产生了巨大影响。核磁共振是一种非常灵活的技术，能够获得其他方法无法获得的信息。磁共振成像在材料科学和工程领域有着巨大的前景，特别是在需要非侵入性测量的领域。我们计划集中在三个方面。多相流(液体和气体的流动)在工业上用于进行催化反应，在核工业中用于冷却核反应堆。燃烧在制造和工程的许多分支中都是至关重要的。空化(由于压力下降而出现在液体中的动态活动气泡)在工业中越来越多地使用。这三个过程对工业都很重要，同时，我们对这三个过程中的传输现象的了解仍然有限。常用的计算方法需要直接的实验验证，这是很难在不干扰正在研究的过程的情况下执行的。磁共振成像作为一种非侵入性技术，在这一领域具有很大的潜力。在所有这些应用中，都有一个由重力决定的自然垂直方向：火焰、气泡和炽热的液体总是向上上升。与气液界面相关的核磁共振测量也存在问题：它们将影响局部磁场，在较高磁场下产生磁化率伪影。这笔资金购买了一台核磁共振磁体，用于研究多相流、空化和燃烧。这样的磁铁必须有一个垂直的孔，以便重力对磁铁内部的样品产生与在工业和自然环境中相同的影响。磁体的磁场将具有中等强度(4.8T)，以减少磁化率伪影，同时保持可接受的信噪比。

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.