Numerical investigation on performance of moisture separator by Lagrangian-Eulerian strategy: Physical mechanisms, theoretical models, and advanced algorithms

摘要

Moisture separator (MS) plays a key role in safe and economic operation of most nuclear power plant of light water reactor. Numerical simulation of two-phase flows is widely used to understand the mechanism of MS, and optimize its design. Lagrangian-Eulerian (LE) simulation strategy is a promising modeling approach that can provide the detailed interaction between droplets and steam, and the size distribution of droplets at a certain time, which is able to depict a complete picture of droplet-laden flows in MS. However, there lacks research on systematically reviewing the state-of-the-art progress on developing practical models used in LE simulation for MS. In this work, the physical understanding of different droplet behaviors, which includes droplet generation, droplet motion, droplet collision, droplet-wall impaction and droplet break-up, are first discussed. Second, the practical models of these droplet behaviors are presented, in particular, the models of droplet generation and droplet-wall impaction are examined in detail. Further, four numerical techniques, which covers from numerical discretization schemes, steam properties interpolation, locating a droplet to collision droplet pair search, are introduced for accelerating the implementation of modeling droplet trajectories in MS. At last, needs for future concerned issues are discussed. (C) 2019 Elsevier Ltd. All rights reserved.