磁共振成像应用于多相流体动力学研究进展

多相流反应器广泛应用于化工、冶金、能源及医药等过程工业，其内部具有非稳态、非线性、非平衡的自然属性，因而对多相流检测技术提出了挑战。准确检测并理解多相流体力学特性、进而揭示并掌握多相流反应器设计及放大规律，一直是当今过程工程领域的前沿课题之一。磁共振成像（MRI）作为一种非侵入式、多维瞬态全流场先进检测手段，可获得准确详尽的多维流场信息，包括颗粒浓度与速度（脉动）场、流型识别、气泡尾涡、颗粒聚团等多尺度流场参数及介尺度流动结构。此外，MRI在数值模型验证与改进方面也具有良好的应用前景。概述了MRI技术原理，重点论述了MRI近年来在气固及气液反应器中的研究现状，展望了MRI在多相流反应器中有待拓展的方向。

Application of magnetic resonance imaging to multiphase fluid hydrodynamics

Multiphase reactors are most widely encountered in chemical, metallurgical, energy and pharmaceutical industries. Because multiphase flow in reactors is generally unstable, nonlinear and non-equilibrium in nature, many challenges are exerted to multiphase flow detection technology. It has always been one of the frontier studies in process engineering to accurately measure and comprehend multiphase hydrodynamics, as well as to discover and master rules for design and scale-up of multiphase reactors. Magnetic resonance image (MRI) technology, an advanced non-invasive detection method, can obtain accurate and detail information of multi-dimensional transient fields, such as transient solid concentrations, velocity (fluctuating) fields, flow pattern recognition, bubble vortex structure, particle clustering, and meso-scale heterogeneous structures. Additionally, MRI could have good prospective applications for validation and improvement of numerical models. This review discussed MRI principle, analyzed current status of MRI application for gas-solid and gas-liquid flow hydrodynamics, and prospected promising future directions.