A Numerical Study on Droplet-Particle Collision

• Published in: Flow, turbulence and combustion Vol. 105; no. 4; pp. 965 - 987
• Main Authors: Vilela Vitor, de Souza Francisco José
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01.01.2020
• Subjects: Area; Catalytic cracking; Computational fluid dynamics; Diameters; Dimensionless analysis; Droplets; Fluid catalytic cracking; Fluid flow; Heat exchange; Industrial plants; Investigations; Isothermal flow; Kinetic energy; Lamella; Learning; Octrees; Optimization; Particle collisions; Particle size; Reynolds number; Statistical methods; Surface energy; Teaching methods; Weber number
• ISSN: 1386-6184; 1573-1987
• DOI: 10.1007/s10494-020-00153-x

This paper investigates the collision between a droplet and a spherical particle for non-reacting, isothermal flows based on the design of computer experiment and statistical learning methods, using the Volume of Fluid method along with a momentum conserving formulation on an adaptive octree grid. It has increasingly been a subject of numerical investigation due to the growing demand for full industrial plant control and processes optimization, for instance, fluid catalytic cracking and wet cleaning of dusty gases.Simulations are first validated against experimental data for droplet-to-particle diameter ratio Dr=1.75, considering the geometrical parameters of the formed lamella, i.e., height, base diameter and remaining liquid thickness on the particle. Since the lamella area is an important factor on mass and heat transfer on common industrial processes, the effects of droplet Reynolds [103–104] and Weber [102–103] numbers on this output are investigated using the design of computer experiment, along with a mechanical energy analysis. At dimensionless post-impact time equal to one, the Reynolds and Weber numbers show a negative and a positive effect on the lamella area, respectively. This is in agreement with our mechanical energy analysis of interfacial flows, since we found that the Reynolds number expresses a potential of liquid and gas kinetic energies exchange, whereas the Weber number expresses a potential of liquid kinetic energy and surface energy exchange. Lastly, a correlation for the dimensionless lamella area as function of the dimensionless time, the Reynolds and Weber numbers is proposed based on statistical learning methods.