Three-dimensional Euler grid approximation method for multi-droplet motions in the steam-water separator

Abstract

Motions of multi-droplets in steam flow are a common and important phenomenon in various fields such as the environment, chemical industry, and energy. To simulate the motion of multiple droplets, a three-dimensional Euler grid approximation method, which applies to structured and unstructured grids, was proposed. Criteria were established to ensure that the motion of droplets is restricted to the grid nodes without compromising accuracy. The method is capable of updating the information of multiple droplets at each calculation step for all nodes and obtaining distribution information including droplet density and velocity. The multi-droplet motions in the steam separator were simulated and velocity field of multi-droplets showed a symmetrical distribution. The multi-droplet motions process in the swirl vane separator of the steam-water separator was also simulated. The results demonstrated that under the studied operating conditions, the critical droplet radius that can be separated by the steam-water separator was 40 μm. The specific positions of droplet-wall collisions were mainly concentrated on the blades and outer wall of the swirl-vane separator, as well as the inner cylinder. The model may serve as a dependable guide for the optimal solution of separation device structures and simulating various other multi-droplet motion processes.